2009 SPE/IADC DRILLING CONFERENCE

Editor’s note: The following abstracts rep- SPE/IADC 118806 mid-program inspections. Through utilization of the resent papers, scheduled and knowledge- cumulative fatigue damage method of fatigue moni- Use of Liner Drilling Technology as a Solution toring, drilling was successfully completed on three sharing presentations, that were scheduled to Hole Instability and Loss Intervals: A Case wells by executing precise and timely pipe section as of 6 January to be presented at the 2009 Study Offshore Indonesia. Steven Rosenberg, rotations rather than pipe inspection. SPE/IADC Drilling Conference, 17-19 March Weatherford; Andrias Darmawan, Liao Jianhua and in Amsterdam. Abstracts have been edited for Chao Zhao, CNOOC SES ; I.B. Budi Utama and Keith space. Hillis, Weatherford. SPE/IADC 119907 Case Histories of a New Wireline Logging Tool The problematic Lower Baturaja limestone for- for Determination of Free Point in Support of mation, known for lost circulation, occurs in the Technical Session: Drilling and Pipe Recovery Operations. Calvin Banuwati field in southeast Sumatra, Indonesia . The Kessler, Daniel Dorffer, Donald Crawford, Rory operator had previously experienced severe losses Case Histories I Dehart and Jerry Weiser, . with wellbore stability issues in this formation with the inability of setting the 7-in. drilling liner at SPE/IADC 119506 A new logging tool identif ies the free point in drill planned depth. The liner had to be pulled out of the collars, drill pipe, tubing or casing for drilling sup- How Continuous Improvement Lead to the hole, leading to the eventual abandonment of the port and well abandonment operations. Unlike previ- Longest Horizontal Well in the World. Kumud existing open-hole section. This resulted in the side- ous free point methods, which used strain measure- Sonowal, Maersk Oil Qatar ; Kwong Ming Wong, K&M tracking of the well. ments of the pipe obtained as a series of stations Technology Group; Bjarne Bennetzen, Maersk Oil with and without the application of pipe stretch or Liner-while-drilling technology was identified as Qatar ; Erhan Isevcan, . torque, this method is simply overlay of two logging the solution because it has minimized or eliminated passes. The first logging pass is recorded with the documented lost-circulation problems , possibly due Maersk Oil Qatar recently completed drilling the pipe in a neutral weight condition, and the second is to the “smear effect” phenomenon. The liner system BD-04A well offshore Qatar , setting world records recorded with tension or torque applied to the pipe. selected provided high torsional capability, as well for both the longest well at 40,320 ft MDRT and the The tool utilizes a property of steel called magneto- as requiring both a mechanical and pressure event longest along hole reach of 37,956 ft . The intro- strictive effect. When a mechanical stress is applied to release the setting tool, minimizing chances for duction of new techniques has allowed existing to steel, its magnetization is modified. When torque premature release. A drill shoe with a displace- constraints to be successfully overcome. This was or tension is applied to the pipe that is free to move, able PDC cutting structure was used to drill the 8 achieved through sound engineering principles and their magnetization will change. If the pipe is not ½-in. hole section. The PDC cutting structure was optimization during the Field Development Plan. free to move, its magnetization will remain the same. This case study will review the history, challenges displaced prior to cementing to allow drill-out with and planning, leading through to the successful drill- a conventional drill bit and BHA . The liner was suc- This tool has many advantages . First, from a rig ing of the BD-04A well. Achievements and improved cessfully cemented in place. safety standpoint, the application of pipe stretch is practices will be discussed, as will the engineering applied only once for a few minutes for the logging analysis of field data where key learning points have SPE/IADC 119903 pass. Real-time operations and 24/7 satellite commu- been shared for future applications . nications allow remote-based operator and service Further Developments in Drill Pipe Fatigue company pipe recovery experts to be involved . The Management: A Case Study. Richard Zoanni and tool is run centralized and does not require weight SPE/IADC 119748 Scott Everage, T.H. Hill Associates. bars for slip engagement . This shortens the tool Case History: Successful Wellbore Strengthening string and simplifies e-line rig-up procedures. Approach in a Depleted & Highly Unconsolidated Demand for the development and implementation Sand in Deepwater . Joseph of a practical drill pipe fatigue management system Fett, Philippe Marchina, Frederic Martin, Claude continues to grow. The result has been the devel- Technical Session: Dardeau , Joel Rignol and Saddok Benaissa, Total. opment of realistic pipe section rotation schemes and implementation of effective inspection interval In early 2008, Total E&P USA sidetracked the scheduling based on incurred fatigue damage rather Extended Reach MC243-A2 well on itsMatterhorn TLP in deepwater than on arbitrary footage and/or hours . Gulf of Mexico. The operations included de-com- SPE/IADC 119373 pleting, sidetracking and re-completing the well, The cumulative fatigue damage technique was Increasing Sakhalin Extended-Reach Drilling which had stopped producing after extended shut-in introduced in IADC/SPE 110076. Recently the cumu- and Completion Capability. Michael Walker, periods during recent hurricanes. A geomechanics lative fatigue damage technique was applied in the Andrew Veselka and Shane Harris, ExxonMobil. study identified that the mud weight/fracture pres- field with promising results. The case study further illustrates the management and modeling of fatigue sure window had essentially disappeared, and that a Extended-reach drilling (ERD) and completion strong potential existed for mud losses in the deplet- damage accumulated in newly deployed drill pipe over a three-well project. Developed in this case capability on the Chayvo field, Sakhalin Island, has ed and highly unconsolidated A reservoir due to the evolved in well design and operational practices to mud weight required in the caprock shales above. study is the pipe management strategy employed to complete the drilling program without the need for increase well reach to over 10.5 km. Learnings and design changes will be discussed using a recent The risk of losses, particularly when cementing the record well, the Chayvo Z-12, as a case study. liner, was a concern. The well would be frac-packed, and if a competent cement column did not reach a Implementation of the operator’s drilling per- sufficient height above the reservoir, the fractur- formance management process and Integrated ing operation would have been compromised. T o Hole Quality technology have enabled continuous strengthen the formation and prevent differential improvement in overall ROP and hole quality. BHA sticking, the decision was made to drill through the designs and operational practices have been modi- reservoir using a “flat rheology ” synthetic-based fied to reduce vibration effects leading to poor bore- fluid with a high concentration and blend of par- hole patterning and micro-doglegs, thus enabling ticles. It allowed the reservoir to be drilled success- higher ROP with a better-quality borehole. Detailed fully and the liner to be run and cemented with full torque and drag modeling, engineering surveil- returns. lance, and lubricants have also led to improved hole cleaning, lower ECDs, and reduced friction effects The high-quality cement bond allowed frac-pack required to drill and complete these wells. operations to be completed successfully. Data from the frac-pack showed that the formation breakdown Chayvo completion design incorporates the use of pressure was lower than the wellbore pressures pre-drilled liners, standalone screens, swell packers, experienced while drilling and installing the liner, and inflow control devices (ICDs) allowing effective suggesting that the designer fluid improved the zonal isolation, prevention of sand production, and fracture resistance of the formation. The results flow control. Management of ICD placement and suggest that using a designer fluid with engineered configuration provides the flexibility for early well bridging particles can have a strengthening effect on life zonal isolation while maintaining cost-effective depleted/unconsolidated formations . non-rig intervention options for the future . The paper will describe the approach taken in the SPE/IADC 118806, “ Use of Liner Drilling laboratory for the fluid design, as well as operational Technology as a Solution to Hole Instability SPE/IADC 119553 practices to apply the treatment on location. and Loss Intervals: A Case Study Offshore Development and Installation of an Extended- Indonesia.” Reach Multilateral Junction. Erick Peterson,

92 January/February 2009 DRILLIN G CONTRACTOR 2009 SPE/IADC DRILLING CONFERENCE

Jerome Eggemeyer, Stephen McKeever and Dennis Nahr Umr formation lies directly above the Shuaiba have been considered hazardous and were avoided Hartwig, ConocoPhillips Alaska; David Bjork, Alex payzone and is typically drilled with 12 ¼-in. bits. in the past. Following standard procedures for explo- Ortiz and Bryan Pendleton, Baker Oil Tools. The Nahr Umr shale tends to slough in shortly after sive operations, arming the gun with the explosive drilling, leading to stuck BHAs and difficulty running detonator had to be done after the electric coiled- A multitude of extended-reach technologies have 9 5/8-in. casing. tubing head was attached to the gun string, creating been used in the West Sak field on Alaska’s North a potentially hazardous situation. Also the length Slope. Significant to the shallow, heavy oil develop- This paper details the directional casing drilling of perforating gun that could run in one trip was ment is the use of multilateral horizontal wells developments that have been accomplished . severely limited . with a junction providing mechanical support and both through-tubing lateral isolation and re-entry SPE/IADC 119459 New technologies make the electric coiled-tubing capabilities. However, as ERD capabilities evolved perforating technique more efficient and safe r : to routinely reach departure to true vertical depth Ultra Extended-Reach Drilling (u-ERD: Tunnel ratios in excess of five to one, multilateral junction in the Earth) - A New Wellpath Design. Robello • An expendable electronic addressable switch technology did not evolve at the same pace. Samuel, Halliburton. component providing an electrical control and safety barrier to each detonator. A new multilateral junction was designed to match Drilling ultra-extended-reach wells and extending current ERD capabilities . It allows lateral liners to the reach to a greater depth requires both improved • A simplified radio-safe detonator incorporating overcome drag limitations by rotating the liner and models and comprehensive analysis. Wellbore fric- safety features. junction to setting depth in one trip and includes tion is an important issue , and optimizing the design positive indicators for successful installation. of well path is an effective means to reduce torque • An electric deployment bar to deploy the guns into and drag. This paper describes a new well path that a live well before the coiled tubing is connected. This paper discusses the evolution of multilateral will allow extending the reach to a greater depth. wells in the West Sak development, the limitations of A successful job using these technologies performed multilateral junctions when used in extended-reach Usually the trajectories are designed with con- in a high-angle well offshore Abu Dhabi, a first for wells, the development and testing of a new multi- stant curvature with well-defined arcs connecting the UAE, will be described . lateral junction, and several successful field instal- the transition between the tangent sections. Even lations. Operation highlights during the completion though the transition between the tangent section SPE/IADC 119877 phase of a multilateral well with a lateral departure and build section, or tangent section and drop sec- to true vertical depth ratio in excess of six to one tion, appears smooth, there will be discontinuity, Vibration Measurements – Time for are included. which will cause stresses in the tubulars, increased Standardisation. Svein Magne Osnes, StatoilHydro; torque and drag, poor hole cleaning and other fail- Per Amundsen, University of Stavanger; Tore ures. To avoid discontinuity, curvature bridge curves Weltzin and Erik Nyrnes, StatoilHydro. SPE/IADC 118705 or transition curves called clothoid spiral can be Unlike most downhole measurements, there is no The Trials and Tribulations of a Long-Reach used . industrial standard for how to sample, process and Well in the Deepwater GOM. Ron Day, BP America ; present vibration data. Measurements from differ- Nesny Pardo, INTEQ; Louise Jacobsen Plutt and The paper presents a new mathematical formula- ent companies cannot be readily compared , and we Ramsey Fisher, BP ; Segun Jebutu and Hans- tion for curvature bridged well path designs. The do not know if the different tools and systems will Christian Freitag, INTEQ. results show that the essential elements of planning a proposed well path are to determine the shape detect the same vibration mechanisms. Additionally, Where the water-bottom topography is irregular, and position of the bridge section, the characteristic vibration specifications of MWD and drilling tools sub sea infrastructure can often be placed in only parameter describing its shape, and position in the from different service providers cannot be com- a few locations above a field. This can constrain well profile. A coupled analytical criterion based pared . access to reservoir targets, particularly when there on the minimum energy of the curve is proposed to This study looks into the physics and statistics of are drilling challenges above the reservoir, like pres- measure the complexity of the well paths. This paper how four LWD service providers conduct and pres- sure ramps or layers with unstable lithologies. Given documents the comparison between the predicted ent their vibration measurements . An analysis is the size of this field, long step-outs are required. mathematical simulation results with the actual tra- conducted to establish if the companies are tuned to This paper presents the strategies implemented to ditional well path designs . look for the same type of vibrations, or if different successfully drill and access reservoirs in a large vibration modes tend to be detected with the various faulted anticline in the deepwater GOM. SPE/IADC 119768 procedures in place. A starting point for an industry The well in question faced three challenges. First, A Study of Temperature-Dependent Friction in standard will be suggested . the well would be the longest step-out (~7,500 ft of Wellbore Fluids. Eirik Kaarstad, Bernt Aadnoy, lateral step out over ~10,000 ft of vertical depth) Tomas Fjelde, University of Stavanger. SPE/IADC 119642 drilled to date in the field. Second, the well targeted a fault block in a portion of the field that was poorly Increased well reach is one of the most important Dry Dope-free OCTG Connections: A Novel constrained due to limited offset well control and a developments in modern drilling. Wellbore friction Environmentally Friendly Technology Validated poor quality seismic image. Third, the well faces sev- plays a central role. However, the industry still uses Through Diverse and Severe Field Conditions. eral wellbore integrity challenges in the form of two the simple one-parameter Coulomb friction model. Gabriel Carcagno, Tomas Castineiras and Ernesto pressure ramps, one unstable slump zone, and one Gallo, Tenaris. pressure regression. The University of Stavanger has conducted friction research to further understand mechanical and vis- Dope-free alternatives for standard thread com- Wellbore integrity management made use of realtime cous frictional effects. The paper will report exten- pound for the assembling of OCTG connections (tub- ECD and bulk-density to optimize drilling, measure sive friction coefficents tables for many wellbore ing and casing) have been commercially available borehole stability and limit formation damage. After fluids from several vendors. A friction apparatus since 2003. This paper describes experiences related drilling to TD, log, formation pressure and image log allowing both linear motion and rotational motion to the field use of a fully dry dope-free solution, the (dipmeter) data confirmed that the well had crossed have been used. The test equipment also includes improvements and adjustments incorporated after an un expected fault in the targeted reservoir sec- a heat element to study the temperature effect on initial experiences and operators feedback, the tion, which caused one of the target reservoirs to be friction . verification activities in laboratory and especially in absent. A sidetrack was successfully drilled. experimental rigs under actual field conditions, and The results of the paper improve the design of summarizes the advantages and the value added long-reach wells. A more correct frictional picture through the use of this type of technology. SPE/IADC 119446 results, and data aid in selecting drilling fluids with High-Angle with 9 5/8-in. best frictional properties. SPE/IADC 119297 Casing in Offshore Qatar. Jason Talkington, Schlumberger; Michael Avery, Occidental Well Design for Environmentally Friendly Qatar ; TBN TBN, . Technical Session: HSE Drilling Systems: Using a Graduate Student Drilling Class Team Challenge to Identify Options for Reducing Impacts. Jerome Schubert Casing while drilling is becoming a powerful method SPE/IADC 119365 in mitigating lost circulation and wellbore stabil- and David Burnett, Texas A&M University . ity issues in offshore directional wells. Programs Minimize Risk and Improve Efficiency Associated that require drilling through unstable formations with Electric Coiled-Tubing Perforating A graduate drilling class was at high angle before entering the productive zone Operations. Alan Salsman, Schlumberger; Hassan challenged to develop a well plan for a rea-life drill- for a horizontal well are becoming more common. Khalil, Abu Dhabi Marine Operating Co.; Feras Abu ing opportunity in a Texas coastal margin. Teams faced this task in drilling hori- Jafar and Fardin Ali Neyaei, Schlumberger. chose among five low-impact drilling scenarios to zontal Shuaiba wells offshore Qatar. The unstable write AFE s for an independent operator. Students Perforating operations with electric coiled tubing were permitted to choose among more than 70 ser-

94 January/February 2009 DRILLIN G CONTRACTOR 2009 SPE/IADC DRILLING CONFERENCE

vices, products, processes or equipment to create a accumulator (CDA) is available, but what is the uniform undercut, full taper, and combined straight unified design significantly lowering the impact of cut-off depth where the CDA is more effective than gauge with taper above. Similar results have been drilling. Each technology was judged on its ability the conventional accumulator? Also, the effects of observed with point-the-bit and push-the-bit rotary to be assimilated into normal drilling operations, its gas compressibility have not been fully addressed in steerable systems. Extension of the gauge length has ability to reduce the well’s footprint, its cost, and its amendments to usable fluid volume calculations. also benefited bent motor operations, but the effects likelihood of acceptance by stakeholders. of various gauge profiles are less certain. Research aims to improve VE calculations from the E&P companies have hundreds of options to reduce standpoint of gas compressibility and fluid power Gauge lengths of 4 in. or greater have been used as the footprint of drilling activities, employ waste man- availability ; determine the most effective operating a standard practice for two years. This paper dis- agement practices, and lower emissions. Harnessing depth range of both accumulators and rigid con- cusses the rationale for use of extended gauges, the graduate student intellects successfully created a duits ; and introduce additional ranking measures of modified profiles used to maintain steerability, and realistic design for an EFD system but also created weight and space efficiencies. This should provide the field performance achieved . a tool to organize and evaluate new practices . subsea design engineers with a set of first-glance guidelines on optimising subsea control systems. SPE/IADC 118298 Technical Session: True Matching of Bit and Multi-diameter String SPE/IADC 119762 Tools Delivers Optimized Drilling Performance Deepwater I Pull Your BOP Stack – Or Not? A Systematic in Gulf of Mexico Salt Applications. Steven Barton Method to Assist You in Making This Multi- and John Clegg, ReedHycalog. Million Dollar Decision. Jeff Sattler, WEST SPE/IADC 119519 Engineering Services. The increased use of hole-opening tools remote from New Riser Design and Technologies For Greater the drill bit has led to a critical need to understand Water Depth And Deeper Drilling Operations. Pulling your BOP stack, particularly in deepwater, the interaction between the drill bit and the hole- Emmanuel Persent, Jean Guesnon and Gerard is one of the singularly most costly events in the opening tool itself. Problems that can result from Papon, Institut Francais du Petrole (IFP) . drilling of a well, if it occurs. Sometimes the stack improper matching include vibration, inability to pull could have been avoided. Avoidable occasions open hole, mechanical damage to string tools or to Deepwater exploration is challenging riser designs , occur for a variety of reasons, including inadequate the bit, and sub-optimal drilling performance. with the present 15,000-psi serial rating becoming information or staff training, unclear understand- insufficient and new designs with working pressures ing of regulatory or company requirements, and This paper explores the theoretical relationship of 20,000 psi or more being considered . The total non-availability of experts to assist in the decision- between bit and reamer and modeling the relative weight of the riser, as well as the required tension- making s. This paper will present case studies where agressivity and stability of both tools, building on ing capacity of the rig, also increase rapidly with the planned stack pulls were circumvented, as well as a established indexes for predicting and comparing water depth. Static loads and fatigue become critical systematic protocol that can be developed prior to the performance of bits. It also considers stabiliza- and may threaten the riser integrity. Further, the starting a well to clearly define the decision-making tion of the hole-opening tool using both concentric natural period of the riser in the disconnected mode process for stack pulls. and eccentric devices. It describes theoretical model- reaches the wave energy window and may put the ing of the vibration behavior of the assembly. It then riser in a dangerous resonant state. describes field validation of the above using a unique SPE/IADC 119427 downhole data recording device . To help solv e these issues, technologies have been Development of the 18 3/4-in., 20,000-psi Subsea developed such as the hyperstatic integration con- Wellhead System for High-Pressure and High- Finally, the paper will review case studies in the Gulf cept allowing an axial load sharing and the hybrid Temperature Applications. Bernard McCoy and of Mexico and demonstrate a link between the theo- choke and kill lines. A study has been performed to Shiva Singeetham, FMC Technologies . retical analysis, the measured validation, and actual assess the potential of advanced drilling riser tech- field results. nologies . This paper presents riser technologies and This paper will present the development of the first describes the results of the study . Finally, it shows 18 ¾-in., 20,000-psi subsea wellhead system rated SPE/IADC 119534 how such new technologies can enlarge the operat- for 0-35°F temperature applications . T he three-year ing performances of risers. development project will be detailed, including com- Novel Concentric Expandable Stabilizer Results ponent design, material selection and processing, in Increased Penetration Rates and Drilling reliability analysis, structural and thermal analysis, Efficiency with Reduced Vibration. Steven SPE/IADC 119606 and extensive prototype testing of the equipment . Radford and Tracy Li, Hughes Christensen ; Mark Surface BOP System Operational Experience Results of the prototype tests will include stress and Jenkins, INTEQ. Offshore Brazil in 1,900 m of Water. Brian Tarr, deflection data and how they compare with industry An inherent problem of drilling and reaming con- Shell; Tor Taklo, Shell; Eirik Sorgard, Shell; Andy standard allowables. currently is that conventional fixed stabilizers run Hudson, Shell; Luiz Olijnik, Cooper Cameron above expandable reamers can be no larger than Corporation; Hongbo Shu, Shell; Jim Schroeder, the pass-through diameter of the restriction above . Technical Session: Bits it and, thus, cannot effectively stabilize the upper This paper presents recent operational experience and Hole Openers BHA, which often results in undesirable vibrations. using a surface BOP system for both drilling and Recent controlled tests have been conducted in twin subsea completion activities offshore Brazil in the wells drilled from the same casing under a full-scale first phase of the Parque das Conchas development SPE/IADC 119625 drilling rig, one well with only a concentric expand- (block BC-10) that encompasses several reservoirs Maintaining Desired Steerability While able reamer and the other with both expandable in up to 2,000 m of water. The Arctic I, a moored Extending Gauge Length to Manage Whirl. Fred stabilizer and reamer. Results showed that the stabi- rig capable of operating in 1,036 m of water using a Dupriest and Steven Sowers, ExxonMobil . lizer produced significant gains in performance. conventional 18 ¾-in. subsea BOP stack and marine BHA modeling predicted lower bending moments riser system, was equipped with a pre-laid mooring This paper discusses the use of increased bit gauge above the reamer when a concentric stabilizer was system and surface BOP system designed for this lengths to mitigate whirl. Lengths in excess of 4 in. utilized. The well drilled with the stabilizer above project . A service vessel was used to pre-install the are now standard in all operations. The modifica- the reamer resulted in higher ROP with lower down- well and subsea pump system conductors, taking tions have resulted in reduced vibrations, significant hole WOB and up to 35% reduction in drilling MSE these activities off the critical path. Also, a subsea improvement in drill rate, improved borehole quality (mechanical specific energy), compared with the well hammer installed the well conductors at each drill and reduced tool damage. drilled without the expandable stabilizer. The stabi- center, minimiz ing time required to move from well lized well had significantly better drilling efficiency, to well for batch drilling and completion operations. Analysis of mechanical-specific energy suggested that 40% of footage drilled worldwide was affected which is attributed to reducing buckling and whirl in The start-up performance of this rig system will be by whirl or lateral instability. In response, an initia- the drill pipe and upper BHA, and reduced frictional presented . tive was begun in 2005 to extend gauge lengths to losses against the borehole wall. Additionally, lower reduce the whirl and constrain the resultant side levels of whirl, lateral and stick-slip vibrations were cutting. Significant improvement was seen in rate of recorded with the new expandable stabilizer . SPE/IADC 118415 penetration and bit life . Developments in Accumulator Technology: Fluid SPE/IADC 119302 Power Options in Subsea BOP Control Systems. Over a two-year period, it was demonstrated that Paul McCurdy, Occidental Petroleum Qatar . steering was not affected with gauge lengths of up to Experimental Study of MSE of a Single PDC 4 in. However, it was necessary to modify the profile Cutter under Simulated Pressurized Conditions. Conventional subsea accumulators are highly of the gauge area to achieve this steerability. The Navid Rafatian, Schlumberger; Stefan Miska, inefficient in deepwater . The constant differential gauge profiles used to achieve steerability included Univeristy of Tulsa; Leroy Ledgerwood, Hughes

96 January/February 2009 DRILLIN G CONTRACTOR 2009 SPE/IADC DRILLING CONFERENCE

Christensen; Ramadan Ahmed and Mengjiao Yu, consists of three main intervals. The top interval University of Tulsa . consists of mostly abrasive sandstone and shale; the Technical Session: middle consists of shale ; and the bottom mostly con- It is believed that impermeable rocks experience sists of limestone and thin beds of shale. Drilling Fluids high differential pressures due to shear dilatancy and become stronger , thus more difficult to drill. The operator attempted to efficiently drill the 16-in. SPE/IADC 119269 However, recent atmospheric and pressurized single- top interval using both roller cone TCI and PDC cutter experiments show that, contrary to this belief, technology. The TCI bits had unacceptably low ROP Design Reduces Cost by Building even at low pressures (100-200 psi) and even with with short bit life . PDC technology delivered accept- Integrity Continuously while Drilling in East permeable rocks, significant increase in mechanical able penetration rates but inconsistent run lengths. Texas. Kenneth Vaczi and James Ryan, ExxonMobil; specific energy (MSE) is observed compared with Shawna Linehan, University of Oklahoma; Miguel atmospheric tests. The experiments were carried A team was organized to seek new PDC bit technol- Mota, ExxonMobil. out in a single-cutter, high-pressure testing facility ogy, state-of-the-art downhole motors, and optimized refurbished with high-precision sensors and data drilling practices to consistently drill the top interval The paper describes the application of a high-solids, acquisition system. A 13-mm PDC cutter was used to in one run. This paper will discuss the modeling high-filtration fluid with engineered particle sizes cut Carthage marble and Indiana limestone samples analyses the team performed to develop the BHA/bit to prevent lost returns in the Trawick field in East with depths of cut ranging from 0.025 in. to 0.050 solution that greatly reduced lateral and torsional Texas. The system is called a drill and stress fluid in . 72 tests were performed on these two rock types vibrations, in addition to the advanced bit design because fracture closure stress and integrity are under confining pressures ranging from 0-1000 psig. technology that improved bit stability. It will also dis- built continuously while drilling. This approach is The confining fluids were either water or mineral oil. cuss how the collaborative effort helped the operator allowing the operator to routinely drill an 800-ft to break new records in drilling the most footage depleted zone with a history of severe losses without Unexpectedly, analysis of the MSE consistently ever drilled in the 16-in. top interval. The application resorting to multiple discrete lost-returns treat- showed that increases in the confining pressure as of this new technology has thus far increased the ments. Protective casing has also been eliminated. small as 150 psi can increase the MSE of the cutting drilled footage by 35% and the average interval ROP process significantly and reduce the cutting efficien- by 22%, resulting in a 30% reduction in drilling cost. In recent years, the variety of particulate treatment cy by half. These reductions in the cutting efficiency systems has been developed to build stress continu- ously. The drill and stress fluid differs because it is that were even more dramatic in the permeable and SPE/IADC 119422 saturated Indiana limestone . a water-based system that is relatively inexpensive, Evolution of Drillable PDC Technology Enables and it arrests fracture growth though the develop- Upon analysis of the results of experiments , a Operator to Safely and Economically Drill ment of an immobile mass within the fracture rather new theory is proposed to explain this unexpected South Texas Gas Wells with Casing. Jarod than through the formation of a blockage at the frac- behavior . DeGeorge, Matthew Isbell, and Eric McClain, Hughes ture aperture. In the case history, the fluid worked Christensen; Michael Doster, Baker Hughes; David successfully in long intervals of permeability of less than 0.1 md. SPE/IADC 119423 Limbert, ConocoPhillips . Advanced PDC Technologies Deliver Significant An operator in South Texas established a casing The paper will discuss the evolution of the well Performance Improvements in the Pinedale drilling program in 2002 to address drilling hazards design to allow successful application of the drill Anticline Production Interval. Mark Freeman, and has since successfully drilled over 100 wells and stress fluid, the pilot program that validated the Hughes Christensen; Jon Gent, Questar Exploration using purpose-built casing-drilling rigs. Given th eir observed increases in integrity, and the operational and Production; James Isenhour, Hard Rock success, the operator was eager to expand use of learnings developed during the pilot program. Solutions. casing drilling to traditional drill pipe rigs. This was easily accomplished in the production hole but more SPE/IADC 119363 A new-generation PDC technology has been applied complicated in the intermediate hole section. The at the Pinedale Anticline field in Sublette County, purpose-built casing drilling rigs used a wireline New Water-Based Fluid Designed for Depleted Wyoming. The development wells target interbed- retrievable BHA with a pilot assembly and under- Tight Gas Sands Eliminates N PT. John Trenery, ded fluvial sandstones and shales of the Lance Pool reamer. Weaknesses in t he wireline retrievable Baker Hughes Drilling Fluids; Erik Hoover, Brigham (Lance and Upper Mesaverde formations). Due to BHAs forced the operator to seek another solution . Oil & Gas ; Gregory Mullen and Saddok Benaissa, surface constraints, all wells are drilled directionally INTEQ; Lawrence Richards, Baker Hughes Drilling from centralized surface pads. To achieve uniform The solution was identified as drillable PDC casing Fluids. subsurface well-spacing, well trajectory is S-shaped, bit technology . The existing drillable PDC casing bit with all directional work occurring before the pay was used primarily for drilling short intervals or for Unconventional gas resources account for 43% of US interval is encountered at approximately 8,500-ft drilling-in liners in relatively soft formations, and gas production, with tight gas representing approxi- MD. The pay interval is then drilled vertically using was not durable enough to drill the entire interval. mately 70% of the unconventional production . A new 6 ½-in. PDC bits to approximately 13,400-ft MD, with The authors will detail how the team developed a water-based mud system addressing depleted tight the final 1,000 ft frequently drilled with diamond- “heavy-duty” drillable PDC casing bit with a series gas reservoirs has been introduced . The new High- impregnated bits. of test wells in 2007 to overcome this challenge. Performance Water-Based Mud originally designed for onshore drilling in mature, depleted tight gas The sequence of interbedded fluvial sandstones and sands in the southern regions of the US can be used shale of the Lance Pool is characterized by moder- SPE/IADC 119461 on other fields worldwide. It is applicable to any ate but erratic unconfined compressive strengths of Casing-While-Drilling 24-in. Surface Section tight gas reservoir where losses or stuck pipe occur. 10 -20 ksi, further complicated by high overburden Enables Operator to Add One Extra Slot pressures and increased hydrostatic pressures from to the Existing Drilling Template and Cut This paper provides a technical overview of its mud weights reaching more than 15 lb/gal. Confining Operation Costs in Offshore Congo. Enis Aliko, performance in a challenging field where massive compressive strengths approaching 100 ksi (exclud- Hughes Christensen – Italy; Alan Phillips, Hughes losses, stuck pipe, twist-offs and other fluid associ- ing formation pressures) are not uncommon . Christensen; Stefano De Luca, Congo. ated NPT is common .

The authors will describe the new PDC bits , reduc- The Foukanda platform offshore Congo comprised SPE/IADC 119378 ing the time in this interval by more than 100 hrs per a seabed drilling template with eight slots that well, an improvement of more than 25% . were pre-drilled with a semisubmersible . Once the Combining Proven Anti-Sag Technologies for platform was installed, the wells were tied back and HPHT North Sea Applications: Clay-Free Oil- Based Fluid and Synthetic, Sub-Micron Weight SPE/IADC 119517 completed. The operator wanted to drill another well to explore another structure of the reservoir, but this Material. David Carbajal, William Shumway, Breaking Records in North Kuwait Deep Gas was not possible because the seabed template inter- Charlotte Burress and Ying Zhang, Halliburton. Fields Drilling 16-in. Hole Sections at Greater fered with the vertical projection of the surface well Depths. Ali Jaffar, Hughes Christensen; Anthony heads. The customary way of securing an extra slot North Sea wells drilled in HPHT areas are known for Brown, Baker Hughes; Maneesh Sharma, Hughes was attempted but caused difficulty when re-enter- presenting barite sag challenges. Fluid densities in Christensen; Mohammed Al-Saeedi, Meshal ing the hole because of the sag of the conventional the 17.5-18.0 ppg range require a high percentage of Al-Khaldy and Sounderrajan Mahesh, Kuwait Oil drilling assembly at the exit of the deflector. barite, and 400°F temperatures can adversely impact Company. rheological properties needed for reliable suspen- To resolve this problem, the operator opted for sion. Further, horizontal and ERD wells can require Drilling the 16-in. hole section in north Kuwait deep casing-while-drilling (CWD) , and the operation specific hydraulic parameters for hole-cleaning that gas fields is challenging due to a lithology consisting enabled the operator to secure the extra slot, to get may entail comparatively high pump rates, which of abrasive sandstone, shale and limestone inter- out of the existing wells ’ trajectory, and to save costs can contribute to excessive equivalent circulating bedded with hard siltstone stringers. The section associated with difficulties when re-entering a con- densities (ECD). typically spuds at depths greater than 9,000 ft and ventionally drilled hole with a casing string.

98 January/February 2009 DRILLIN G CONTRACTOR 2009 SPE/IADC DRILLING CONFERENCE

A non-barite manganese tetraoxide weighting agent Studies showed that Na/K formate system resulted SPE/IADC 119819 has proven to provide equivalent anti-sag at a lower in less damage compared with conventional mud Drilling and Completing the First US Offshore cost than micronized barite . The manganese tetraox- systems. The formate fluids gave a high return Gas Storage Wells in Mobile Bay, Alabama. Robert ide weight material has been tested in a clay-free permeability, up to 70%, after circulating the corre- Fulks, Weatherford; Douglas Cagle, MoBay Storage and economical paraffin/mineral oil-based fluid . This sponding washing fluid. Two damaging mechanisms Hub . paper details the design and testing of the system, were identified: external filter cake and potassium including extreme HPHT static aging and sag testing chloride precipitation. Compatibility tests indicated The paper discusses the technical challenges in and modifications to the emulsifier package. that precipitate formed due to mixing of filtrate with drilling and completing the first offshore gas stor- formation brine that contains large amount of chlo- age reservoir in the United States. A depleted gas SPE/IADC 119567 ride. Lab tests imply that formate brine had low cor- field in the environmentally sensitive shallow water rosion rate when the pH of the solution was main- of Mobile Bay, Ala ., known as the Dauphin Island Successful Drilling of a Deviated, Ultra-HTHP tained above 9. On the other hand, the corrosivity of field was determined capable of serving as a stor- Well Using a Micronised Barite Fluid. Michel K-formate brine increases in the presence of CO due 2 age facility a fter a two year geo mechanical analysis. Gregoire, Total; Michael Hodder, Shuangjiu Peng and to the formation of formic acid. The results of this The paper describes the drilling and completion of Jarrod Massam, M-I SWACO. study were implemented on several gas wells. 26 wells in the severely depleted Dauphin sands. This paper reviews the design and application of In order to inject and withdraw gas for connec- a micronised barite (MB) fluid to drill a deviated SPE/IADC 119973 tion to various interstate natural gas transmis- HTHP well in the northern North Sea. The key Advances in API/ISO Standard Grade Purified sion pipelines, MoBay Storage Hub, together with technical challenge was to avoid sag of the weight Poly-Anionic Cellulose (PAC) and Drilling Weatherford and Schlumberger, engineered 21 hori- material. On a previous well, using an API-barite- Grade Xanthan Gum (XG) Test Procedure and zontal gas injector/withdrawal wells in the uncon- weighted fluid, sag had resulted in considerable NPT . Specifications Definition. Andrea Balestrini, solidated Dauphin sands with porosity above 30% Lamberti USA ; Antonius Maas, Kelco Oil Field The MB fluid was used to drill the section from 6,354 and permeability as high as 4500 mD. The reservoir Group; Keith Morton, Chevron; Mac Seheult, Kelco had been continuously drilled since the early 1990s m to 7,327 m, and the well was successfully drilled Oil Field Group. to TD . No significant sag occurred, and as a result, and was exhibiting pore pressure of less than 50 psi as the project commenced. The poor rock strength considerable time savings were achieved on flow This paper will describe the technical work per- required the use of expanable sand screens in the checks, trips and cementing operations . formed to develop reliable and reproducible test- shallow completions to allow subsequent injection/ ing procedures for standard purified Polyanionic drawdown activity. SPE/IADC 118659 Cellulose Polymers (PAC) and Drilling Grade Xanthan Gum Polymers (XG), leading to new specifi- Quantitative Formation Damage Evaluation The program is documented in the paper, along with cations limits in API 13 A/ISO 13500 . The new specs lessons learned. Using Dynamic/Static Drill-in Fluid Filtration include the following : Tests Data. Liang Jin, Shell. • For PAC, moisture content, fluid loss and viscosity . SPE/IADC 119942 Quantifying near-well bore formation damage by Kicks In Offshore UK Wells – Where Are They drilling and completion fluids at dynamic and static • For XG, moisture content, particle size analysis Happening, And Why? James Dobson, Health & conditions is important for a field development drill- and viscosity. ing and completion concept selection. This paper Safety Executive. presents an evaluation methodology that combines The final procedures and specifications for both PAC The proposed paper will review the frequency of results from dynamic/static filtration tests, returned and XG will be published with the new revision of kicks on the UK Continental Shelf over the last permeability tests, and SEM tests on real cores with the API 13 A/ISO 13500 in January 2009. 10 years, looking at trends in relation to the level actual exposure time to fluids during drilling and of rig activity. It will look at frequency of kicks in completion into a well performance model to estab- the different sedimentary basins and the types of lish an invasion profile along the open-hole section Technical Session: operations in which they happen. There will be a to quantify the impact on the production of the well. . more detailed review of incidents over the last three Complex Wells years. It will look at the factors, both geological and SPE/IADC 119212 operational, that contributed to their frequency. It Improve Drilling Performance by Controlling SPE/IADC 119440 will attempt to identify possible steps reduce that frequency. Risk and Reducing Non-Productive Time in a Significant Step Taken to Eliminate Sustained Challenging High-Temperature, High-Pressure ‘B’ Annulus Pressure in Major North Sea HPHT The paper will identify where potentially hazardous Well. Ole Iacob Prebensen, Gunvald Nesheim and Development. Liz Hunter and Bill Kinnaird, incidents are still occurring in what is now a mature Svennung Vidvei, M-I SWACO; Reagan James and Halliburton; Michel Gregoire, Total. province, and why. Trygve Anda, ConocoPhillips Norge. Long-term isolation of the gas-bearing Hod has One requirement on a challenging HPHT well in the been an issue in Central Graben HPHT , leading to SPE/IADC 118961 North Sea was to drill the well without replacing the costly management and maintenance of sustained The Use of a Novel Rigid Setting Fluid for Well existing drill pipe on location. As the hydraulic win- “B” annuli pressure. Six clear steps were taken to Isolation and to Cure High Rate Losses, Pumped dow was narrow, maintaining the configuration of achieve life-of well isolation: Through Drilling BHAs in the Southern North the drill pipe limited the ECD . At the same time, the Sea. Chris Couper, Halliburton; Donald Macarthur temperature regime was high. An oil-based drilling 1. Analyses to predict failure mechanisms across all and Dougie Scott, RWE Dea UK. fluid (OBM) with treated micronized barite (TMB) well events were carried out . Results were similar, was chosen as the solution . Simulation software also identifying risk areas, the main being cement- Several lost-circulation materials (LCM s) are avail- enabled real-time hydraulic values to be displayed formation debonding at the change to lightweight able to help minimize down time while combating during the operation . completion fluid. lost circulation. In general, fine- to medium-sized particulate-based materials mixed into the mud 2. Effect on risks were investigated by altering well system are the first line of defence. When this fails, SPE/IADC 119445 parameters . Most effective reductions were made by the common response is coarser LCM, which often Formation Damage Induced by Formate Drilling altering mechanical properties of the cement. cannot be pumped through downhole tools. This Fluids in Gas-Bearing Reservoirs: Lab and paper discusses a practical, field-proven solution Field Studies. Hamoud Al-Anazi and Mohammed 3. Extensive lab analysis was used to develop the using a right-angled, temperature-activated fluid Bataweel, . best solution. A cement slurry was designed provid- ing optimum mechanical properties . that, once set, exhibits similar characteristics to Formate-based drill-in fluid was used for the first Portland cement. time to drill gas wells in Saudi Arabia. Gas wells 4. A full-scale yard trial qualified the design for the The cases discussed in this paper are located in the were completed in sandstone reservoirs where field . 43/19a Cavendish field in the Southern North Sea, temperature range between 280-310°F. Na/K formate whilst drilling through Platten Dolomite. This is a mud was used to drill these wells with required mud 5. The large volume job was carried out with the rig thin, complexly folded and rafted dolomite that is weight ranges between 90-102 pcf. Studies were cement unit. found within the Zechstein halites. This formation conducted to optimize mud formulation to meet drill- 6. Since placement, the annulus pressure has been presents significant well control challenges with the ing operation requirements and to explore possible recorded. No abnormal pressure has occurred in 24 potential for high overpressures coupled with high induced formation damage. Compatibility tests were months since completion. rate dynamic losses,. The novel fluid was used to performed , and corrosivity of formate brine was cure dynamic losses of up to 400 bbl/hr. studied on tubing alloys .

100 January/February 2009 DRILLIN G CONTRACTOR 2009 SPE/IADC DRILLING CONFERENCE

SPE/IADC 119909 Work on carbon sequestration in subterranean for- Carlos Siso, ConocoPhillips Canada; Don mations has renewed interest in investigating the Reinheimer, Schlumberger. HPHT Drilling – New frontiers for Well Safety. long-term effects of CO on Portland cements, which Rubens Junior and Otto Santos, ; Paulo 2 will react with the injected CO . Work is ongoing to Zonal isolation and cement sheath integrity are key Ribeiro, Universidade Estadual de Campinas. 2 improve the long-term effectiveness of the wellbore requirements for heavy oil development and produc- tion. Current commercial production techniques In a scenario of huge investments in the quest for sealant. Efforts have focused on enhancing the prop- use steam to provide heat to mobilize oil and allow new oil and natural gas discoveries, the oil industry erties of Portland cement by reducing the perme- production – like steam-assisted gravity drain- has reached a consensus: no easy fields to be devel- ability of the set cement, lowering the concentration of materials in the cement that react with CO , or age (SAGD). Maintaining cement sheath integrity oped remain undiscovered, especially in offshore 2 prevents unwanted fluid migration, especially oil, environments. New and old challenges on well drill- replacing the conventional Portland with specialty gas and/or steam. Flexible cement systems can be ing such as drilled extensions over 6000 m, sub-salt cements . Additional work has been done in evalua- designed and installed so that the cement sheath drilling, very narrow operational windows, opera- tion of the long-term stress environment of the well. can withstand the expected stresses in the well. tional problems like lost of circulation, stuck pipe, This work goes beyond the simple drilling and com- Installation practices are critical to providing a high- and kicks are aggravated when drilling in high pres- pletion of the well to include input from long range quality cement sheath. Challenges that are prevalent sure and high temperature (HPHT) environments. reservoir and wellbore stress modeling through the full life cycle of the well. in SAGD wells are centralization in the soft forma- In the world’s exploratory context, the occurrence tions, assessment of the cement bond between of HPHT areas is an increasing trend. It is the This paper discusses various solutions to the selec- the cement and formation, and assessment of the tion of a proper wellbore sealant for a CO injection cement bond after steaming. materialization of the worst case scenario for well 2 drilling and safety, formed by great challenges and well. Additionally, the paper reviews the available This case history will compare two cement systems operational, environmental, and economic risks. sealant technologies, their application, and includes with flexible properties installed in seven SAGD well Field experience has shown that the economical a discussion of stress modeling for these wells. pairs (14 wells) in Alberta . Zonal isolation and well- risks have been overshadowed by the great pre- bore integrity are examined with the use of cement mium target: increments on reserves. However, if SPE/IADC 119415 bond logs and ultrasonic cement evaluation tools. the well safety aspect is dealt with the conventional Innovative Computer Model Increases These logs provide evidence that zonal isolation is approach, the oil industry is at risk of losing its Success Rate When Placing Deep Kick-off achieved and is improved with the use of industry investments, causing great impacts to the environ- Plugs in Southern Mexico. Lenin Diaz, Mathieu best practices for cement placement. ment and also to the company’s image. Since HPHT Pasteris, Juan Flores, Willie Dakduk, Wilfredo well construction costs are so much higher than Espinoza, Frederico Justus and Nicolas Flamant, those of traditional wells, the scope of knowledge SPE/IADC 119535 Schlumberger. and science on well safety, once limited to kick pre- Guidelines for Appropriate Application of Non- vention and well control contingencies, are now an Wells in Southern Mexico usually go deeper than Foamed Ultralightweight Cement Slurries. James integral part of the technical and economic feasibil- 5,000 m. Over the years, service companies have had Curtis and Mohamad Dajani, BJ Services Co . ity of well construction. to place consecutive cement plugs to successfully kick off, particularly in wells deeper than 3,500 m. Well cementing advances have enabled the use of Within this context, this work surveys the best Several plug failures made it clear that the success ultra-light weight (ULW) cement slurries with densi- HPHT techniques and procedures practiced by rate must be raised. A study was performed with ties as low as 7.5 ppg without foaming. These slur- the oil industry, presents the new researches and a simulation allow ing for engineered optimiza- ries often achieve significant compressive strengths, trends and shares some valuable lessons learned tion of the plug placement design and that shows even at moderate or low curing temperatures. on Petrobras’ operations in Brazil and throughout how a 100% success rate in plug cementing can be However, there are opportunities for disaster when the world. achieved in wells as deep as 6,614 m, with hard for- conventional cement slurry design criteria, labora- mations and an OBM environment. tory testing procedures and field practices are inap- SPE/IADC 119458 propriately applied to ULW cementing applications. The new software value resides in a live analysis The Impact of Multilateral Drilling Technology and display of the fluid interfaces, mixing both while This paper will discuss the relevant issues that must in Meeting the Field Development Objectives traveling down the drill pipe and up the annulus and be taken into account when planning a successful for the Castilla Field in Columbia – A Case resulting in the output of an estimated top of uncon- ULW cement operation, including materials selec- History in Improving the Drainage Efficiency taminated cement after pulling the pipe out of hole. tion, liquid volume fraction, surface and downhole of the Guadalupe Reservoir. Orlando Mercado, This workflow displays the effect of each variable densities and rheologies, compressive strength test- Ecopetrol SA; Steven Fipke, Halliburton; Ricardo affecting the amount of contamination of the cement ing procedures, quality control measures, blending Rojas Moreno, Sandra Rodriguez and Alberto Florez slurry downhole, giving the engineer the possibility and bulk handling, operating error margins and on- Anaya, Ecopetrol SA; Jorge Velez, Halliburton. to optimize the plug placement design before job the-fly mixing control systems. The Castilla field, located 250 km southeast of execution. Bogota, Colombia, was discovered in 1969 and origi- SPE/IADC 119296 nally was developed with vertical wells. It produces SPE/IADC 119386 Zonal Isolation Achieved in Kashagan Field heavy oil from the Guadalupe reservoir (Upper New Lab Tests and Models Improve Planning for Through Integrated Approach . Krishna Ravi, Cretaceous), which has strong bottom aquifer water Complex Cementing Jobs Offshore New Zealand. Halliburton; Nevio Moroni, ENI; Carmen Repetto, drive. Ecopetrol completed the first horizontal well Iain Parr, Shell; Sarah Farnworth, Stuart Lee and Agip KCO; N Dettori, ENI. there in February 2001. In 2005, a 7-well cluster Ronald Sweatman, Halliburton. design was used to increase reservoir exposure and The primary purpose of the production liner in the delay aquifer water influx effect. In 2006, the feasi- Recent investigati ons into cementing highly deviated Kashagan field is zonal isolation , but the challenges bility of advanced well architecture was evaluated offshore liners in New Zealand employed laboratory are magnified due to the presence of corrosive with the objective of increasing oil sweep efficiency, tests and numerical models to determine the best fluids (CO2 and H2S), rock properties and high pore avoiding bypassed oil in the K2 reservoir due to con- way to prepare the hole and complete the cement pressures. The cement sheath was designed for ing and minimizing water production. job. Newly developed testing included: mud film test- structural integrity, lower permeability and chemical ing using mud, spacer and cement; ultra-low shear stability. The structural integrity helped prevent the It was recommended that several TAML Level 4 rheology (ULSR) testing under downhole conditions formation of micro-annulus and cracks during well multilateral wells be drilled to replace the nine to determine mud and cement static gel strength operations . The cement sheath was also designed directional wells originally planned . The result has development, as well as erodibility of the mud by to withstand completion and subsequent operations been increased exposure in K1 and K2 reservoirs; spacer and cement; dynamic high-angle sag testing over the well life . The cement system was formu- reduced drawdown pressure to produce K2; reduc- (DHAST) for mud and spacer; dewatering and filter lated to withstand well operations by improving tion in water production ; and higher estimated final cake build-up testing of mud, spacer and cement the elasticity. The potential for carbonation was oil recovery per well. Lessons learned are presented . using the FannB . decreased by lowering permeability and reducing the components in the cement sheath that could

This paper will highlight the testing and provide react with CO2. Technical Session: results, which have greatly aided the understanding of the cement, mud and spacer interactions with the The cement system has been successfully deployed Cementing formation . in four wells. The cement bond logs verified the successful cement slurry placement on all jobs, and SPE/IADC 119267 subsequent successful well operations confirmed the SPE/IADC 119960 zonal isolation. The same cement system is being

Improving Wellbore Seal Integrity in CO2 Flexible Cement Improves Wellbore Integrity deployed in additional wells . Injection Wells. Glen Benge, ExxonMobil. in SAGD Wells. Gunnar DeBruijn, Schlumberger;

102 January/February 2009 DRILLIN G CONTRACTOR 2009 SPE/IADC DRILLING CONFERENCE Technical Session: Tubulars

SPE/IADC 119357 Analysis of Complex Wellhead Load Events for Conductor and Surface Casing Strings. Albert McSpadden and Simon Glover, Altus Well Experts.

The analysis of thermal-induced wellhead growth and resultant loads can be critical for tubular stress design and failure analysis of platform wells. But standard simulation tools don’t account for some common complex wellhead loading events . Analysis of wellhead growth and loads from first principles is used to investigate these complex load events. Particular attention is given to conductor and sur- face casings, and some non-intuitive conclusions are discussed. Case studies are presented to illustrate a range of field applications . SPE/IADC 119861, “ Axial Force Transfer of Buckled Drill Pipe in Deviated Wells. “

SPE/IADC 119552 drilled and completed in the presence of H 2S , rium equation for the pipe. The effective force then Evaluating the Expandability and Collapse requiring high-strength sour service-rated tubulars. emerges as a natural combination of pipe force Resistance of Expandable Tubulars. Jun Agata, S uppliers overcame critical metallurgy challenges and fluid force terms. Numerical examples will be Eiji Tsuru, Mitsuru Sawamura, Hitoshi Asahi and to widen technical options, including heavy wall calculated . Hidefumi Tsugihara, Nippon Steel Corp . casings and high collapse manufactures; dedicated products such as 110 ksi for mild sour use, or thick This paper summarizes the results of a study to DST strings used in extreme HPHT wells. These Technical Session: assess the mechanical integrity of expandable improvements paved the way for 125 ksi mild sour tubulars in monobore wells, and understanding the service C125 grades. Deepwater II tubular material behavior as it is being expanded. T his paper will discuss various high-strength sour Described herein is an experimental setup that sim- SPE/IADC 119651 ulates the expansion process, and the development service tubulars, their relative applicability , basic of a finite element model . manufacturing techniques to optimize tubular, as Improvements in Efficiency for Subsea well as NACE testing to characterize sulfide stress Operations in Deepwater Angola. Jason Zook, Test results show that the variation of wall thickness cracking resistance.” ExxonMobil; Arran Keith, Coremax . around the circumference of the pipe is amplified when the axial load in increased, which results from SPE/IADC 119861 Esso Exploration Angola (EEAL) has substantial the restraint condition in the wellbore. For both improve d the efficiency of subsea operations in the the experimental and the numerical simulations, a Axial Force Transfer of Buckled Drill Pipe in deepwater environment of Angola Block 15 (AB15), strong correlation was observed between pre- and Deviated Wells. Stephane Menand, Hedi Sellami and dedicating a work vessel solely to subsea activities . post-expansion pipe wall thickness variations, and Ahmed Bouguecha, Paris School of Mines; Patrick EEAL also evaluated improving efficiencies during it was also concluded that the magnitude of the wall Isambourg, Total; Christophe Simon, Drillscan. simultaneous operations . This paper will present thickness variations of the expanded pipes is depen- case histories of the various operations such as Axial force transfer is an issue in deviated wells dent on the work hardening rate of the original non- close tolerance well positioning, suction embedded where friction and buckling phenomenon take expanded pipe. In addition, the collapse resistance plate anchor handling and horizontal christmas tree place. The general perception is that once drill of the expanded pipe was found to have degraded installation, both on and off line . pipe exceeds conventional buckling criteria, axial when the restraint condition was applied. force cannot be transferred down hole anymore. This paper shows that, even though buckling criteria are SPE/IADC 105578 SPE/IADC 119468 exceeded, axial force transfer could be still good if Achieving Improved Performance Through New Standard for Evaluating Casing drill pipe is in rotation. Results from a drill string Drilling Optimization and Vibration Connections for Thermal Well Applications. mechanics model show will show how axial force is Management Process at a GoM Development Jaroslaw Nowinka and Daniel Dall’Acqua, Noetic transferred down hole in many simulated field condi- Project. Louise Jacobsen Plutt, BP; Nesny Pardo, Engineering . tions: sliding, rotating, with or without dog legs. INTEQ; Allen Pere, BP; Edgar Rodriguez, INTEQ.

Casing connections in thermal well applications This paper should contribute to reduce unpredict- Challenges at the GOM Atlantis field include direc- such as SAGD and CSS (cyclic steam stimulation) able lock-up situations and improve axial load trans- tional control, drilling efficiency, wellbore integrity experience extreme loads due to exposure to high fer performance. and vibration management. Expandable reamers temperatures 200°C-350°C, stresses exceeding the are used to drill thin bedded alternating sands and elastic limit, and cyclic plastic deformation. To SPE/IADC 119954 shales. This drilling configuration can result in high date, no standard procedure has been adopted by levels of vibration . Over the past two years, a contin- Fluid Momentum Balance Defines the Effective the industry to qualify casing connections for such uous improvement cycle has been established, based Force. Robert Mitchell, Halliburton. conditions . This paper introduces a new connection on comprehensive pre-well planning, downhole data acquisition with real-time diagnostics and thorough evaluation protocol, designed specifically for thermal Effective force is a concept developed for including post-well analysis. This provided an accelerated well applications . It employs analytical and experi- the effects of the surrounding fluids on the pipe. learning curve from each well . mental procedures to assess performance of a can- The paper that defined our current understanding didate connection under conditions typical of service of pipe-fluid interaction was written by Klinkenberg, in thermally stimulated wells. Especially in the intermediate interval, this has with essential discussions by Arthur Lubinski and proven particularly critical. In offset wells, no well Henry Woods. However, there’s been a shift in point The ISO has opened a work item to consider adopt- in this interval had been successfully drilled in one of view from the pipe to the fluid. What information ing it as an international standard. run. By monitoring downhole environment in real can we obtain from a simple balance of momentum time so personnel could react immediately to damag- of the fluid in bulk? For example, for flow inside a ing vibrations , this section was drilled in one run in SPE/IADC 119888 pipe, we can determine exactly the load exerted on the five consecutive wells drilled, and all formation Latest enhancements in High-Strength Sour the pipe by the flowing fluid in terms of only the fluid evaluation data acquisition and directional objec- Service Tubulars. Frederic Bernard, Vallourec density, pressure and momentum. tives were met with low hole tortuosity, facilitating and Mannesman; Bruce Urband, GrantPrideco ; casing placement. This paper also will address fluid dynamics. Most Garth Lynn, Bruce Bradley and Cedric Linne, papers about effective force have dealt with static Vallourec & Mannesman; Frederic Legay, Vallourec & fluids. How are these static effects modified for a SPE/IADC 119523 Mannesmann. flowing fluid? General equations for the balance of The Structure of Currents in the Deepwater Gulf More and more deepwater, HPHT wells are being fluid momentum will be combined with the equilib- of Mexico. Steven Anderson, Matthew Cadwallader,

104 January/February 2009 DRILLIN G CONTRACTOR 2009 SPE/IADC DRILLING CONFERENCE

Horizon Marine ; Sergei Frolov, Accurate In late 2007, while drilling Chevron’s Big Foot #3 • Logistic lines are long and tedious. Environmental Forecasting ; James Feeney, Horizon appraisal well in the deepwater GOM, an extremely Marine . mobile tar zone was encountered subsalt at 20,800 • Water depths range from 50 m to extreme depth. ft. Unsuccessful attempts were made to convention- Three phenomena dominate the mesoscale ocean ally drill through the tar to deepen the well. It was • Heavy ice and formidable ridges compel an exodus variability in the Gulf of Mexico : loop current, anti- determined that the tar had to be cased off in order mid-winter through mid-summer . cyclonic (warm core) eddies, and cyclonic (cold to continue drilling. Further, due to the extreme tar Against these challenges, a fit-for-purpose vessel core) eddies. In the early years of GOM deepwater mobility, the liner must be drilled through the tar. exploration, it became apparent that the loop cur- has been optimized for extended-season operations rent regularly shed anticyclonic eddies that drifted A service provider had recently developed a tar liner in the Arctic and off-season performance in a more west across the Gulf. Original analysis and models drilling tool that allowed the concurrent running of hospitable environment. assumed that these eddies have simple elliptical a 11 7/8-in. liner while drilling oversized hole below shapes and that they could be sufficiently described the liner shoe utilizing a bit, motor and concentric SPE/IADC 119287 with a few geometric parameters. reamer, with returns taken up the inside of the cas- ing . This paper will discuss the implementation of Probabilistic Well Time Estimation Revisited. However, o bservations have proven that this is not the tool on three succesive attempts before finally Adrian Adams, Colin Gibson and Bob Smith, Nexen the case. Each eddy var ies in shape, structure, dura- successfully casing off the tar zone 55 days after Petroleum . tion, movement and intensity. Cyclonic eddies, which encountering it. were generally ignored early on, have been found to Probabilistic estimation of well duration has been play a significant role in the changing dynamics of common practice for over a decade , yet several the loop and eddies. Oceanographers are now incor- SPE/IADC 119818 essential aspects of both data characterisation and probabilistic analysis have been overlooked . A porating these features in their dynamical models. A Seasonal Solution for Offshore Drilling in an database of over 100 central North Sea wells was Ice Environment. Bruce Keener and Rod Allan, independently re-analysed for NPT . Extreme NPT Acoustic doppler current profilers (ADCPs) mounted Transocean. on workboats are now commonly used for ocean events ( over 2.5 days) were only 4% by number but current surveying to supplement data from drifting Offshore drilling in the Arctic environment is becom- contributed 51% of NPT by duration. It is shown that buoys, satellite remote sensing, and rig-mounted ing more feasible , though obstacles are formidable: mechanical parent NPT, mechanical extreme NPT, current meters. Real-time monitoring of both open water WOW, and riser-connected WOW are all near-surface and mid-water currents is critical . • Leases may only be ice-clear a few months a year. statistically distinct, with different occurrence fre- Strategically planned survey patterns are followed quencies and probability density functions . to best observe and forecast the encroachment • Fall and early winter months expose severe of oceanographic features into areas of sensitive weather analogous to a North Sea wind and wave The statistical data apply to central North Sea operations. The data can be used operationally and environment. wells only. The method itself may be used to to initialize a forecast model . develop data and time estimates for any drilling • Winterization measures must consider potential of location, given a sufficiently large well database . severe icing. SPE/IADC 118901 • The vessel hull and exposed machinery must toler- SPE/IADC 119437 Implementation of Novel Tar Casing Drilling ate temperatures of -40°C. Tool in Deepwater Gulf of Mexico. John Connor, Application of Active Heave Compensated Cranes Arifun Djamil, Chevron; Charles Newhouse, Hess For Mobile Offshore Drilling Units. Tonnes • The ice management strategy must anticipate Corp ; Tommie Graham, Dril-Quip . Seierstad and Jeremy Ogg, National Varco. operations in one-year ice .

DRILLIN G CONTRACTOR January/February 2009 105 2009 SPE/IADC DRILLING CONFERENCE

Nearly all subsea operations require crane support previously been available only with memory-quality SPE/IADC 119884 at the seabed. Since the 1990s, various field support formation evaluation measurement data. This paper Drilling Automation: Technologies, Terminology and offshore construction vessels with high-capacity will describe the rationale behind the deployment of and Parallels with Other Industries. John active heave compensated (AHC) subsea cranes two telemetry drill strings (4-in. and 5-in. strings) Thorogood, Drilling Global Consultant; Walt Aldred, have provid ed a cost-effective alternative to using into underbalanced and horizontal drilling applica- Schlumberger; Fred Florence, NOV M/D Totco; semis. tions in California. The completed document, sup- Fionn Iversen, International Research Institute of ported by data from actual well examples, will detail Stavanger. A modern drillship or semisubmersible is normally the benefits gained from the combined technology of equipped with large knuckle boom pedestal offshore a high-speed drillstring telemetry network interfaced Drilling automation is a rapidly developing area of cranes for handling provisions and personnel. with complex downhole bottomhole assemblies . technology where associated jargon is fast-evolving Handling pipe, casing and risers are either done by and different terms are used by different groups the same cranes or dedicated special cranes, and Of particular focus will be a discussion of the value to refer to similar concepts, with the potential for subsea support work is generally conducted with the added by the real-time transmission of downhole confusion and misunderstanding. Th is paper will derrick and motion compensator. New crane tech- annular pressure for ECD management, stick-slip describe concepts already in operation and under nology is being implemented in semi and drillship measurements for vibration management, instan- development and to classify them into of key catego- designs that introduces crane types capable of act- taneous downlink commands to rotary steerable ries. The more significant interface requirements ing as the traditional knuckle boom pedestal cranes, systems and memory-quality formation evaluation will be identified, and key safety concerns will be with or without pipe-handling functions. With addi- measurements to improve and wellbore highlighted. Parallels will be drawn with other indus- tional systems and functions, these cranes can also placement . tries to demonstrate analogues and suggest direc- perform AHC subsea lifting operations. tions for further developments . This paper will discuss some of these new crane SPE/IADC 119965 types and their functions and areas of application. Multi-Parameter Autodrilling Capabilities SPE/IADC 119761 Provide Drilling, Economic Benefits. Fred Remote Automated Directional Drilling Through Florence, Ryan Fox, Mike Porche and Randall Rotary Steerable Systems. Hernan Melgares Thomas, NOV. Technical Session: Escalera, Will Grace, Claudio Alric, Dennys Moreira, Drilling Automation Computers and programmable logic controllers Arturo Romo, Luis Gonzalez, Leonardo Toco, Goke (PLCs) have significantly increased the capabili- Akinniranye and Julio Palacio, Schlumberger . ties of automated drilling devices . An electronic The evolution of rotary steerable systems (RSS) has SPE/IADC 119570 auto-drilling system was developed to provide been rapid in the past several years. However, the steady-state weight at the drill bit and/or differential Step Change Improvements with Drill String increase in directional drilling activity is challenging pressure across the motors. Recent field tests dem- Telemetry at Occidental of Elk Hills, Inc (OEHI). the deployment of sufficient experienced directional onstrated that the system improved WOB and ROP Chris McCartney, Scott Allen, Oxy Oil and Gas ; drillers (DD). This paper describes an automated and provided favorable attributes like controlled Mike Reeves, IntelliServ ; Maximo Hernandez, method for drilling directional wells remotely with reaming, smooth kick-offs, protection against surge GrantPrideco; Danial MacFarlane and Azaad Baksh, RSS, which has been successfully deployed in pressures and a soft landing for bits . The system, Baker Hughes INTEQ. Mexico. The DD is located at the operation support when combined with computing and data acquisition center with the ability to remotely control the mud Breakthroughs in MWD, LWD and drillstring telem- technology, can optimize drilling by controlling the pumps. An automatic trajectory program compares etry systems are allowing informed decisions to rig braking system while simultaneously examining the current well trajectory with that planned and be made in real-time based on insight that had multiple drilling parameters.

106 January/February 2009 DRILLIN G CONTRACTOR 2009 SPE/IADC DRILLING CONFERENCE

SPE/IADC 119965, “Multi-Parameter Autodrilling Capabilities Provide Drilling, Economic Benefits.”

proposes the best steering command for the RSS. Balov, StatoilHydro; Mike Herbert, ConocoPhillips Once the command is accepted by the DD, the Norge. system remotely controls the rig pumps to execute the downlink sequence and change the downhole Friction tests are performed at regular intervals, settings of the RSS. This system allows a few experi- and measurements are used to monitor trend enced DDs to control multiple operations . variations in order to detect poor hole-cleaning or increased borehole tortuosity. The quality of the detection can vary greatly with the work load and SPE/IADC 118769 experience of the drilling staff. Real-time measure- Pattern Recognition-Based Remaining Useful Life ments through data servers make it possible to auto- Estimation of Bottom Hole Assembly Tools. Dustin mate and systemize the monitoring process. Garvey, Joerg Baumann and Joerg Lehr, Baker Hughes INTEQ; J. Hines, University of Tennessee. This paper presents a computer system to sys- tematically analyse real-time data in order to This paper will describe a new pattern recognition- monitor downhole conditions. Such a system can based system for estimating the remaining useful utilize much more data than friction tests because life of BHA tools. Industry is shifting towards simple mechanical, hydraulic and temperature models can condition-based maintenance approaches, which use calculate predicted hook load and surface torque in design guidelines and rough operational thresholds any drilling conditions. to assess individual tool health. In th at approach, a large amount of tool performance and environmental T he system has been run on recorded data from data are not effectively incorporated into the health three wells on the Statfjord oil field in the North assessment process. Using real data collected from Sea. A data filtering technique has been developed a rotating steering system tool, the prognosis system and applied to solve problems with noisy and erratic is shown to be able to predict the remaining useful real-time signals. With correct input parameters, the life of individual tools with an accuracy ranging from system has clearly indicated unexpected measure- 0.88 to 8.76 hours over three test sets. ments just prior to a lost-circulation problems.

SPE/IADC 119808 SPE/IADC 119650 Enhanced Real-time Wellbore Stability Real-Time Optimization of the Drilling Process – Monitoring Using High Definition Imaging With Challenges in Industrialization. Erik Dvergsnes, Wired-Pipe Telemetry. Christopher Wolfe, INTEQ; Eric Cayeux and Fionn Iversen, International Stephen Edwards, BP; Ansgar Baule and Stephen Research Institute of Stavanger. Morris, Baker Hughes. A new drilling control system for real-time optimi- Despite pre-drill geomechanical modeling to define zation and automation control was recently tested the mud weight window, many wells still experi- offshore in the North Sea and is now entering an ence significantly non productive time associated industrialization phase . It is based on application of with wellbore instability. This can be attributed to advanced real-time process models for calculation of many factors but is predominantly due to the lack of both hydraulic and mechanical forces. Results from appropriate data while drilling. Since rock proper- the calculation modules are applied directly in the ties, stresses and pore pressure often vary from the drilling control system, affecting parameters such as pre-drill model predictions, critical wells frequently pipe acceleration, velocity and deceleration and the require real-time updating of the geomechanical pump startup profile. models using LWD data. Here we give an overview of lessons learned from A case history is presented where memory-quality, field test and discuss how important challenges high-definition LWD image logs were obtained via revealed during the test can be solved. We also high-speed telemetry systems and used to assess discuss how such a system will benefit from future wellbore conditions in real time . technology with a higher degree of automation than the present equipment . SPE/IADC 119435 SPE/IADC 119660 Early Detection of Drilling Conditions Deterioration Using Real-Time Calibration of A New Stick-Slip Prevention System. Age Computer Models: Field Example from North Kyllingstad, National Oilwell Varco. Sea Drilling Operations. Eric Cayeux and Benoit Daireaux, International Research Institute of In 1988 (SPE 18049), it was demonstrated experi- Stavanger; Brikt Hansen, StatoilHydro; Mohsen mentally that stick-stick oscillations could be cured

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Services; Marc LeBlanc, Ryan Energy Technologies; Gregory Kostiuk, Canrig.

The paper describes how a computer-controlled top drive can address slide drilling problems. It presents its advantages in setting downhole toolface orienta- tion and compares with current practice. The paper explains further improvements in drilling efficiency and toolface control in four case studies using field data and log analysis .

In directional drilling with conventional steerable motor systems, solving the problems of toolface set- ting and control are fundamental. The application described provides solutions to both these problems in a manner the driller and directional driller can readily understand. Deviated wellbores produce sidewall frictional forces, which render slide drill- ing less effective than rotary drilling. The system described provides an oscillation program which reduces these frictional forces.

Results are based on four case studies, using field data from three US onshore wells and one well drilled offshore China. Observations are backed up with drilling performance data. Conclusions drawn are: that significant improvements in reducing rig flat time can be achieved using the toolface setting capabilities of the application; that the oscillation program improves delivery of weight to the bit; that fine control of toolface while in the slide drilling SPE/IADC 118656, “ Applying Precision Drill Pipe Rotation and Oscillation to Slide Drilling mode improves wellbore directional control . Problems.” SPE/IADC 119959 by smart control of the rotary drive. Instead of keep- SPE/IADC 119851 Innovative Design Rotary Steerable Technologies ing the rotary speed constant, it was varied propor- Confidence Limits Associated With the Earth’s Overcome Challenges of Complex Well Profiles tionally to the torque fluctuations measured directly Magnetic Field Used for Directional Drilling. in a Fast Growing Unconventional Resource by a kelly bushing torque meter. Since then, several Susan Macmillan, British Geological Survey; Stephen – Woodford Shale. S andeep Janwadkar, Baker stick-slip prevention systems have been introduced. Grindrod, Copsegrove Developments ; Allan McKay, Hughes INTEQ ; Steve Simonton, and Donald Black, Cimarex Energy . This paper presents a new stick-slip prevention Petroleum GeoServices. method that is simpler and more robust than the The declination, dip angle and total field strength of In Oklahoma’s Woodford Shale , complex torque feedback method. It is based on the same the Earth’s magnetic field are used with magnetic well profiles with negative vertical sections idea – that the rotary drive impedance should be survey tools for surveying the wellbore. These values and extended-length laterals are required adjusted to partly match the characteristic string are often obtained from mathematical models, such to maximize productivity. This posed impedance in order to absorb torsional wave energy as the British Geological Survey Global Geomagnetic challenges such as excessive slide around the stick-slip frequency. But in contrast, it Model (BGGM). The BGGM is updated annually to drilling time, difficulty controlling does not require any measurements of torque and maintain accuracy. However, a global predictive well trajectory, unacceptably low acceleration. Field test results will be included. model cannot capture all sources of the Earth’s penetration rates, high torque magnetic field, which results in uncertainties of the and drag. Engineers deter- predicted parameters. mined that wellbore tortous- Technical Session: ity and high friction factors The Industry Steering Committee on Wellbore caused inefficient trans- Directional Drilling Surveying Accuracy (ISCWSA) published a MWD fer of weight on bit and error model in 2000 (SPE 67616). Since then, more reduced ROP. SPE/IADC 119661 accurate data from magnetic survey satellites have been introduced into the BGGM and the uncertainty Existing rotary Targeting Challenges in Northern Areas Due to of the predicted geomagnetic field parameters has steerable Degradation of Wellbore Positioning Accuracy. been reduced. systems are Torgeir Torkildsen, Jon Bang, SINTEF Petroleum typically cost Research; Bjoern Bruun, StatoilHydro; Stein In this paper’s approach, clean orientated magnetic prohibitive Havardstein, Total. down hole data is simulated using geomagnetic for this observatory data. Spot absolute measurements of applica- Due to proximity to the magnetic and geographical the magnetic field made at observatories around tion/ poles and the prevalence of magnetic storms in the the world are adjusted for the crustal magnetic field auroral zone, precise wellbore positioning becomes to make them applicable to hydrocarbon geology. more challenging as drilling activities approach The adjusted observatory data are then compared northern areas. This paper addresses the targeting with the predicted values from the BGGM to assess challenges posed by drilling in far north regions. uncertainty. The uncertainties do not fit a “normal” SPE/IADC 119959, The Barents Sea (75°N) and the Northern Sea (60°N) distribution so they are expressed as limits for vari- “Innovative Design were compared. Surveys with six magnetic (MWD) ous confidence levels. They vary with time , loca- services and two gyroscopic services were simulated tion and, in their derivation, do not assume any Rotary Steerable in realistic wellbore geometries. Wellbore position underlying empirical error distribution. Options Technologies Over- accuracies were analyzed at both latitudes. to further reduce the uncertainties using data come Challenges from local magnetic surveys (in-field referenc- When moving from 60°N to 75°N, geological targets of Complex Well ing) and observatories (interpolation in- must be expanded horizontally by 60%-100% to field referencing) are also described . Profiles in a Fast accommodate for increased wellbore position uncer- tainty. This holds for all surveying services and all Growing Unconven- wellbore geometries in our study . As an example, SPE/IADC 118656 tional Resource – the horizontal uncertainty (95% level) at 7,000-m MD Applying Precision Drill Pipe Woodford Shale.” of a combined gyro and MWD survey is ±250 m at Rotation and Oscillation to Slide 75°N, compared with ±140 m at 60°N. Drilling Problems. Colin Gillan, Nabors; Scott Boone, Epoch Well

108 January/February 2009 DRILLIN G CONTRACTOR 2009 SPE/IADC DRILLING CONFERENCE environment. A new rotary steerable system, specifi- of a rotary steerable tool below a high-torque PDM provides information about expected signal tenden- cally designed for 3-D wellbores for low-spread-cost provided the benefits of both conventional PDM and cies , EM transmission is heavily influenced by the land-drilling applications, uses an automated rotary RSS drilling by delivering faster rotation per minute extreme resistivities of thin beds, which are hard to steerable rib-steering closed-loop system. Since its (RPM) at the bit and continuous rotation of the drill include in the simulations. The comparison between introduction , many wells have been drilled in North string. The increase in RPM reduced vibration per- actual measurements and resistivity logs showed America with build/drop of 8°/100 ft. In the Woodford petuation and transmission in the rest of the drill correlation. Case studies illustrate the different rela- Shale, the new system , coupled with advanced BHA string. The PDM dampened S&V and mitigated the tionships between simulations, actual measurements modeling software, has significantly improved drill- effects of stick/slip. The combination of PDM and and resistivity of the formation over depth . ing performance . Drilling complex well profiles with RSS had a positive impact on the life of the bit and negative vertical sections have increased the length downhole tools and resulted in an increase in both of laterals by 350 ft . Days required to drill the lateral drilling and average rate of penetration. Technical Session: interval have reduced by 30%. This paper will present a detailed study of this fit- Managed for-purpose solution to increasing footage per day, SPE/IADC 119260 mitigating S&V and dramatically reducing risk in Pressure Drilling& Drill String Vibration Mitigation During directionally drilled wells. Simultaneous Drilling and Hole Enlargement. Underbalanced Stefano Mancini, Graham Hitchcock and J . Opsahl, SPE/IADC 118872 Halliburton. Signal Attenuation for Electromagnetic Drilling Drill string vibrations can create significant issues Telemetry Systems. Jochen Schnitger and John in operations requiring simultaneous drilling and Macpherson, INTEQ. SPE/IADC 119442 hole enlargement because of the complex BHA dynamics involved in simultaneously creating two Electromagnetic (EM) systems are used for MWD Control Requirements for High-end Automatic hole sizes . Using case history data, this paper telemetry during drilling. Their deployment is only MPD Operations. John-Morten Godhavn, describes the application of a hole-enlargement tool successful when the signal does not vanish in noise. StatoilHydro. that generated minimal drill string vibration during Knowing the attenuation profile with depth of an EM Automatic control solutions for drilling are expected deepwater drilling and simultaneous enlargement signal is a helpful guide for predicting successful to become widely used in the near future. Basic operations, leading to successful completion of well deployment. This paper details case studies on dif- PID and other more advanced control tools are objectives. ferent attenuation profiles in North America. well established in other communities like offshore Specific design features are discussed, including The case studies were conducted by first simulating processing systems and oil refineries. Drilling sys- dormant and deactivation capabilities that allow the signal attenuation against depth. The simula- tems, however, have traditionally been operated normal drilling hydraulics to be used while not tions were based on available resistivity logs from manually. There is a great economic potential for the enlarging the hole; an articulated arm that enables wells . The actual signal strength was then measured introduction of automatic control to reduce drilling cutting arm “auto-blocking” to reduce the likelihood by an EM surface system at the wellsite, with a field time, increase regularity and improve performance of vibration due to arm movement; and a self-stabi- operator logging the measurement against depth. in managed pressure drilling (MPD) operations. lized tool body that helps minimizes BHA vibrations. The results of the simulation and the measured sig- Narrow drilling margins, especially in depleted res- nal strength were compared against the resistivity ervoirs, ask for highly accurate pressure control. log of the local area. SPE/IADC 118870 StatoilHydro applied automatic MPD operations suc- The Evolution of Rotary Steerable Practices to EM signal generally attenuates exponentially cessfully offshore at Kvitebjoern in the North Sea in Drill Faster, Safer and Cheaper Salt Sections in against depth, although this is highly dependent on 2007 , and several MPD projects are being prepared. the Gulf of Mexico. Robert Clyde and Marco Aburto mud and formation resistivities. While simulation This paper presents results from Kvitebjoern and Perez, Schlumberger. discusses automatic control requirements for drill-

Drilling salt in different regions implies different drilling practices and challenges. Due to the variable range of salt properties and because of the impact on non productive time, to date there has been no substitute recognized for salt drilling experience.

The is continually pushing to drill longer, faster and safer salt sections. The first push-the-bit rotary steerable salt-drilling run in the Gulf of Mexico was executed in 2000. Since then, more than 150 runs and almost half a million feet have been drilled in salt with this type of rotary steerable system. This paper summarizes the analy- sis of push-the-bit rotary steerable runs in the North American Gulf of Mexico, concluding the successful drilling assembly design and drilling techniques to yield optimum salt-drilling performance .

SPE/IADC 119428 A Fit-for-Purpose Combination of Positive Displacement Motor and Rotary Steerable Systems Delivers a Step Change in Drilling Optimization in Tomoporo Field: A West Venezuela Case Study. Danny Ochoa, Julio Palacio, Goke Akinniranye and Aamer Zaheer, Schlumberger.

Wellbore instability, differential sticking and weak sand zones are common problems drilling direction- al wells in the Tomoporo field in western Venezuela . The use of conventional positive displacement motors (PDM) escalates the risk of stuck pipe when difficult sliding and low ROPs increase exposure to open-hole conditions. Rotary steerable systems (RSS) mitigate some hazards. However, high shocks and vibrations (S&V) in laminated formations result in downhole tool failure and unplanned bit trips.

In this case study, a drilling assembly consisting

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Massoud Field. Hani Qutob, Weatherford; Ali Berkat, Khelil Kartobi, Amine Mazouzi, Okba Dhina, ; Naiem Barakat, Weatherford.

Hassi Messaoud is the largest oil field in Algeria. The reservoir was discovered in 1956 and produces from a Cambrian-age at an average depth of 3400 meters depth (TVD). It currently produces oil from a thick Cambro-Ordovician sandstone formation.

Sonatrach introduced tech- nology to the Hassi Messaoud field in Algeria in 2001. Well xxx is the 37th well drilled underbalanced in the field. In this well, the focus was on produc- tion improvement with minimum formation damage, with a secondary objective of increasing the rate of penetration . Another objective was the evaluation of production while drilling and to minimize borehole instability, especially when drilling in the R2 section of the reservoir.

New systematic and dynamic procedures were intro- duced, taking into account proper UBD candidate screening (geology, geomechanics and reservoir) ; calculating the actual reservoir pressure before UB mode starts; and completing the well in UB mode. This well proved to be the best well drilled underbal- ance in the field in terms of reservoir benefits and characterization .

SPE/IADC 119387 Implementation of Middleweight Fluids, Between Lightweight Air or Foam Fluids and Heavyweight Conventional Fluids. Taylor Green, Total.

Development of reservoirs with less-than-normal pressure gradient has led to novel systems deliver- ing equivalent mud weights of 4-8 ppg. These are not lightweight fluids like air or foam and aren’t as dense as conventional fluids, which can be thought of as heavyweight fluids in this context. A water- base middleweight system has been developed that facilitates injection and removal of air in the drilling rig’s circulation loop. It has been in field trial with a low-pressure cavitation mixer and yard-tested with high-pressure porous membrane mixer.

A low-pressure middleweight fluid has been field- tested. 8.7-ppg fluid was fed into the cavitation mixer, which added a stream of air, discharging a lightened fluid into the rig pump. This was used to drill horizontally with lower pressure, higher ROP , no hole problems and no rig pump problems. SPE/IADC 119402, “ Revolutionising the Top Drive for Improved Efficiency and Uptime on a Major Equivalent weights 5-8 ppg were successful. International Drilling Contractor’s Rigs .” A high-pressure version has been yard-tested. The same 8.7-ppg fluid is used and air is injected on the high-pressure side of the rig pump before flowing ing operations. These requirements include a speci- 4000 bbl of mud is lost when the intermediate sec- into rig standpipe. The fluid flows through tubes fied accuracy for a set of normal operations, such as tion is drilled using conventional techniques. This is made of porous media. These tubes are in a pressur- pressure set point step changes, rate changes and due to a combination of natural fractures and weak ized chamber, where air is injected into the fluid, for set point ramping during connections, surge and rock. equivalent density required . swab, and down-linking, and some failure opera- tions, such as power loss, kick/well control and During the development stages of this new process, blocked choke. The paper also includes some ideas an annular pressure sub was run to gather diag- SPE/IADC 119882 for the future of intelligent drilling operations with nostic data. Analysis of the data shows up to 3-ppg Drilling Wells with Narrow Operating Windows increasing automization. variation in circulating density, fracture re-opening Applying the MPD Constant Bottom Hole Pressure gradient of approximately 8.3 ppg and huge circulat- Technology – How Much the Temperature ing density variations during connections. The new and Pressure Affects the Operation’s Design? SPE/IADC 119964 strategy results in equivalent circulating densities Maurizio Arnone, Paco Vieira and Fabian Torres, A Novel Strategy for Reducing Well Cost in the as low as 5 ppg using conventional water-based mud Weatherford. Piceance Basin by Using ECD Measurements and systems, allowing wells with a very narrow mud weight window to be drilled safely. Air Injection through a Parasite String. Zimuzor Narrow pore/fracture pressure gradient margins is a Okafor, Goke Akinniranye, Shannon Higgins and real drilling hazard scenario, where a slight change This simple approach avoids the use of complex Tom Bratton, Schlumberger. in bottomhole pressure conditions could lead to multiphase models, giving the flexibility to quickly NPT if fluid losses and/or gas kick situations occur. arious strategies (underbalanced drilling, casing deploy the technique to the well site without the Constant bottomhole pressure (CBHP), a variant of while drilling) have been deployed to tackle signifi- need for expert personnel . managed pressure drilling (MPD), enables “walking cant loss circulation and stuck pipe problems on the line” between pore and fracture pressure gradi- top of the Mesa in the Piceance Basin . This paper SPE/IADC 119641 ent. The objective is to drill with a fluid so that the describes a new technique that involves acquiring bottomhole pressure is constant, whether the fluid real-time circulating density measurements and con- A New Systematic and Dynamic UBD Procedures column is static or circulating. trol of mud weight in the annulus, using direct air Applied to Prevent Formation Damage, Wellbore injection through a parasite string. Approximately Collapse and Improve Oil Production in Hassi

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CBHP methodology involves accurately determin- tions on floating rigs and on fixed installations and study, transient and steady state multiphase flow ing the change in bottomhole pressure caused by provides case studies of significant time and cost modeling, final drilling program, training, safety, dynamic effects and compensate with an equal savings resulting from the use of MPD equipment contingencies, directional planning for geosteering change in annular wellhead pressure. The bottom- and techniques. with MWD/LWD, lessons learned and production hole temperature and the hydrostatic head of the enhancement results. drilling fluid column increases with the well depth, SPE/IADC 119912 and both parameters have opposing effect in the resultant static and dynamic equivalent density. First Application in Mexico & New World Depth Technical Session: An increase in the hydrostatic and dynamic head Record for MPD Concentric Nitrogen Injection increases the equivalent fluid density due to com- to Drill Horizontal Wells in Low Pressure Rig Equipment pression, but an increase in the temperature causes Reservoirs at Samaria Field. Corrado Lupo, a reduction in the equivalent fluid density due to Schlumberger; Antonio Urbieta, Pemex Reforma; thermal expansion. Oscar Ramirez Lamus, Colombia ; Jose SPE/IADC 119402 Castellanos de la Fuente, Schlumberger; Gustavo Revolutionising the Top Drive for Improved Conventionally, these parameters considered togeth- Puerto and Jorge Bedoya, Blade Energy Partners. Efficiency and Uptime on a Major International er results in a cancellation of effects. In reality, this Drilling Contractor’s Rigs. Craig Fraser, Hitec assumption is false, and the effect on a MPD CBHP The Samaria field in southern Mexico is one of the Products Drilling; Glenn White, Rowan Drilling UK; operation through narrow operating windows can- country’s oldest . Formation pressure in these natu- Edgar Depeuter, Letourneau Technologies . not be ignored due to the potential impact. Precise rally fractured carbonates has been decreasing over estimation of static and dynamic equivalent fluid the last 20 years, with current values down to 0.4 Apart from changing from DC to AC motors, the densities is essential . This paper evaluates the effect gr/cc SG. MPD techniques were implemented using basic design of a top drive has remained the same, of the temperature and pressure on the equivalent nitrogen injected through drill pipe to avoid lost cir- i.e., motor(s) connected to a gearbox, driving a density while drilling a section with narrow opera- culation, formation damage and differential sticking. shaft. A new type of top drive has now been devel- tional windows using CBHP MPD. However, the significant amount of nitrogen inside oped . A major drilling contractor analys ed their rig the drill pipe generates important limitations for downtime and found that the most failures (40%) SPE/IADC 119875 current MWD tools. were related to gearbox issues (gears, bearings and seals). Another significant failure was with motors. Offshore Managed Pressure Drilling Experiences The need for horizontal wells to increase the drain- A lack of available spare parts exacerbated prob- in Asia Pacific. Steve Nas, Julmar Toralde and age area had become a priority , thus directional lems. Kevin Fisher, Weatherford. control and LWD capabilities had to be prioritized. The nitrogen concentric injection technique was Th e drilling contractor decided to help develop a MPD can deliver significant cost savings offshore, then taken into consideration to bring solutions to direct drive top drive with fewer parts, no gearbox and both subsea and surface stacks on floaters the MWD pulse signal transmission and downhole and improved motor. These systems have been field- have been used for MPD . Drilling with a so-called temperature handicaps. This paper describes expe- trialed with significant success , and the drilling closed wellbore using MPD equipment has proven rience gained in the planning and execution of the contractor has decided to fit these top drives to its to be beneficial on all rig types and well types. All first horizontal well drilled using nitrogen concentric complete fleet of rigs (31 land rigs, 31 jackups), and drilling, logging and completion installations can string injection in the Samaria field, also recorded the first DNV-certified 750-ton version is being retro- be safely executed using MPD equipment. On most as the deepest-ever concentric injection point (4,171- fitted on a jackup in the North Sea. installations, only minor modifications are required m MD/4,117-m TVD). The paper will discuss the to enable a closed-wellbore system MPD . This paper design, planning and execution process: geological Technical and field data will be presented , along describes experiences with MPD equipment installa- review and candidate selection, pre-engineering with discussion regarding retrofitting on older plat-

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SPE/IADC 119470 Test of a BOP/Riser Connection with an External Inflate (EI) Inflatable Packer. David Vaucher, Christopher Parrish and Robert Brooks, TAM International .

In deepwater, a leak detected after latching the lower marine riser package (LMRP) can cost up to a staggering $6 million in lost rig time. Clearly, there is a need to be able to test the BOP/riser connection for pressure integrity at surface before running to depth with the LMRP. This paper describes a procedure to test for leaks inside the BOP/riser connection at the moon pool. All connections are tested off-line . Once placed inside the BOP above the riser connection, the tool is inflated to a predetermined pressure, and pressure is applied from above or below the tool to test the various component connections. By observ- ing the applied pressure, it is possible to confirm the presence or absence of a leak, as well as its location.

SPE/IADC 118890 Electrical Cranes and Winches for Improved Safety and Better Operational Performance for Use in Extreme Weather Conditions. Hege Kverneland, and Arne Austefjord, National Oilwell Varco.

Exploration has moved into more hostile and chal- lenging areas like the Barents Sea, onshore in north- ern Siberian territories, and in hot desert areas like SPE/IADC 119777, “ Drilling at the Limit, Can Your Top Drive Handle It? ” Sahara and the Saudi Arabian desert. As a result, hoisting and drilling equipment must be designed to operate reliable and safely in extreme temperatures. This may be a problem for hydraulically powered equipment, which are highly temperature-dependant .

A new electrical winch using permanent magnet (PM) motor technology has been implemented on hoisting appliances ranging from small manrider winches to large offshore cranes. This technology using an “inside-out” PM motor integrated in the winch drum was introduced to the offshore market two years ago, in a manrider winch application. It is now adapted to larger horsepower winches.

This paper will focus on the benefits of using elec- trically powered cranes in extreme-temperature environments. Improved operational performance with higher availability of the equipment, easier installation and maintenance, as well as HSE issues will be discussed. The paper will focus on PM motor technology . It will also discuss the enhanced safety aspect for emergency lowering operations in offshore cranes for a PM motor compared with AC motor.

SPE/IADC 119777 Drilling at the Limit, Can Your Top Drive Handle It? Eric Deutsch, WEST Engineering Services. SPE/IADC 118890, “ Electrical Cranes and Winches for Improved Safety and Better Operational As deepwater drilling has advanced, the weight Performance for Use in Extreme Weather Conditions. ” expected to be borne by a top drive has increased to levels at or near the advertised load rating of the machine. However, the single load rating number form drilling rigs and availability of this technology water-based mud systems, and typically a minor normally associated with a top drive model (e.g., to others. amount of fluid seepage was relied on to lubricate 1,000 tons) is a nominal figure that does not apply the packer. In order to achieve complete containment to every operating situation. A typical top drive of non-aqueous drilling fluids (NADF), it has become SPE/IADC 119292 has two main load paths – hoisting and drilling. common practice to apply higher closing pressure to Hoisting load passes through the elevators and link Improving the Reliability of Slip Joint Packer the sealing element which has reduced lubricity and hanger, while drilling load passes through the saver Systems. Thomas Upton, ExxonMobil. led to premature wear of the sealing element and sub, IBOPs and main shaft bottom end connection. occasional critical failure of packer elements. The loss of drilling mud past the primary sealing Limitations inherent to rotary-shouldered connec- element of marine riser slip (telescoping) joints has In order to contain NADF in the event of failure tions can lead to diminished drilling load capacity been a recurring source of spills. This paper dis- of the primary packer system, the operator now vis-à-vis hoisting. Further complicating matters is cusses work processes and equipment arrangements employs an independent backup pressure supply the fact that the drilling load path is governed by implemented to improve the sealing reliability of slip system that automatically energizes the lower pack- disparate API specifications: 7 and 8C , which pro- joint packer systems. er in the event of loss of pressure in the primary vide different calculation guidelines with regard to system . The operator has also established a routine safety factors and are subject to a certain amount of Slip joint packer designs have not changed signifi- inspection and surveillance program intended to interpretation. cantly since they were first introduced in the early detect slip joint problems before they result in acci- The result is confusion about how much load a 1960 s. They were originally designed for use with dental NADF discharges. top drive can realistically handle. A 1,000-ton top

112 January/February 2009 DRILLIN G CONTRACTOR 2009 SPE/IADC DRILLING CONFERENCE drive may not be officially rated to hoist 1,000 tons SPE/IADC 119321 through its IBOPs. Additionally, API sets forth a Identification and Qualification of Shale different load rating for the swivel bearing, so load Annular Barriers Using Wireline Logs During rating for rotation differs from overall top drive load Plug and Abandon Operations. Stephen Williams rating. This paper discusses the technical aspects and Truls Carlsen, StatoilHydro; Arne Guldahl, of top drive load rating and clarifies the usable load Schlumberger; Kevin Constable and Nils Eriksen, capacity of a top drive in real-world conditions . StatoilHydro .

It has long been recognised that during and after Technical Session: drilling through certain formations, the rock moves inward and begins to close off the well. Normally this Risk Management phenomenon is considered undesirable . However, it can be put to good use as the mechanism to create & Mature Fields an annular barrier behind casing. To extend the life of North Sea brown fields, many well slots on pro- SPE/IADC 118378 duction platforms and sub sea templates are being re-used. This involves permanent plug and abandon- Under-Rig-Floor Open-Hole Logging in the Gulf ment of the old well track , and regulatory require- of Thailand: Operational Implementation of the ments dictate that double barriers be in place . With Oil Industry’s First Simultaneous Open-Hole the shortage of sufficient traditional cement barri- Wireline Logging and Drilling Operation. Eric ers, these wells often need costly remedial work in Upchurch, Chevron; Kyle Graves, Apache. order to meet abandonment requirements.

Chevron Thailand has introduced the world’s first Traditional sonic and ultrasonic azimuthal bond simultaneous open-hole wireline logging and drill- logging provides information on the material imme- ing operation on its tender-assist and jack up rigs. diately behind the casing. Many such bond logs The concept of the new logging technique: The rig show solid material behind the casing far above the drills a hole section and moves to drill another well, theoretical cement top. Clear correlations of this leaving the recently drilled open hole available for bonding pattern with shales, known to cause prob- simultaneous off-line open-hole logging. The rig lems during drilling, indicates that the cause of the returns within 2-3 days to run casing after logging is good bond response is that the shale has sealed off completed. This creates an additional 10% savings the annular region. Logging and pressure-testing per well. sealed-off zones in a number of wells allowed the bond log response to be qualified for a certain for- SPE 116335 detail ed the design aspects of this log- mation. In this manner, it can provide a clear answer ging system. This paper will describe the processes of whether shale successfully seals off certain zones used to implement this system, as well as its inher- and consequently provides a natural annular barrier. ent risks and rewards. In the case of this new tech- SPE/IADC 119321, “ Identification and Qualifi- nology, our phased approach to implementation has This technique has been employed successfully on cation of Shale Annular Barriers Using Wireline resulted in a smooth, incident-free introduction to over 30 wellss. the various rig sites . Logs During Plug and Abandon Operations. ”

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SPE/IADC 119695 The operator restarted a cold-stacked platform rig to drill a five-well ERD program from an existing The Successful Application of Combined New platform. This paper will focus on the key elements Technologies to Reach Isolated Hydrocarbon of the project that resulted in execution success. The Reserves Offshore Dubai. Thomas Lagler, Dubai paper will also describe the results and associated Petroleum - SPD; Jonathan Rhodes, Niall Drumm, learnings during the program, including the signifi- Wael Al Kholy, Baker Hughes INTEQ; Mouad Al Haj cant improvement in ROP , as well as the marked and Gamal Iskander, M-I SWACO. reduction in overall NPT n. In the mature offshore Dubai province, in order to access isolated hydrocarbon reserves, it is neces- SPE/IADC 119746 sary to expose unstable sections of troublesome Case History: Automated Performance shale during drilling. Wellbore time based instability Measurement of Crews and Drilling Equipment. issues have been experienced in the Aruma and Ketil Andersen and Per Sjowall, StatoilHydro; Eric Laffan shales on offset wells with shorter build-up Maidla, PathFinder Energy Services; Buddy King, sections. To minimize exposure time, it is neces- Consultant; Gerhard Thonhauser, TDE Thonhauser sary to drill these sections as efficiently as possible, Data Engineering. minimizing the time these shales are exposed. Dubai Petroleum looked at a combination of technologies A new method and tool has been developed to available in the market that could help them to opti- automatically measure the performance of crews, mize drilling and to meet directional objectives. drilling equipment and downtime , making it pos- sible to compare equipment and crew best practice For controlling the shales, a high-performance performance a cross installations. The system was water-base mud (HPWBM) system with triple inhi- tested on Kristin, Gullfaks, Snorre, and West Epsilon bition was proposed ; also, a performance drilling in the North Sea. system (rotary steerable tool in combination with a modular motor) and drilling dynamics sub were The event recognition tool measure how long time introduced. SPE/IADC 118898, “ New Washpipe Technol- it takes to do each task and by using the following ogy: Why Operators Should Care. ” formula: Downtime time + Equipment technical limit The section was drilled safely in a single run, with time + Crew handling time = Operation time. all drilling objectives achieved and breaking all pre- Valhall is a compacting and subsiding field becoming vious 24-hours ROP drilling records for an offshore When this information is plotted as histograms, it’s a difficult drilling environment in the overburden Dubai Petroleum well. No shale instability issues easy to see the time distribution of each individual with time. The largest impact is in the crest of the were experienced, including the longest Aruma shale task and this provides: section ever drilled by Dubai Petroleum . field. This has led to the installation of flank plat- forms to access flank reserves effectively and the • The management a tool to select the best vendor abandonment of the ERD drilling program. A new SPE/IADC 112486 when it comes to time performance of equipment to waterflood platform was installed in order to provide do the task (technical limit of equipment). Drilling and Completion Challenges of the water injection into the depleted crest. This paper Statfjord Late Life Project. Claas Van der Zwaag, presents the technology developed for de-risking • The crews to find a safe way of working that have Ove Hoevring, Geir Loeklingholm, Jamie Andrews, wells going into the most depleted, compacted crest- optimal performance (best practice) . Olaf Steensland, Synnoeve Lind Rygh and Knut al area with the most overburden changes. Taugboel, StatoilHydro. • The management and crew to find a way to set The computational geomechanics technology devel- the best key performance indicators (KPIs) for each The further development of the Statfjord field for the oped and implemented is presented. The technology task to set targets for crew performance and when late-life pressure blowdown phase requires the drill- is based on a finite element based geomechanics bonuses should be paid out . ing and completion of many infill wells from existing model to calculate stresses, strains and displace- slots. The overall objective is to maximize oil pro- ments. The results are exported from the finite ele- duction in the short term whilst securing future gas ment model to GOCAD in order to do wellbore stabil- SPE/IADC 119383 delivery potential for the late-life phase. ity calculations using BP’s Well Planning Toolkit. In An Aggressive Approach to Reducing Failure- this environment, one can also use supporting data Driven Non-Productive Time in Onshore well designs to meet this objective is as 4D seismic from the permanent life of field seis- Operations. Jeffery Everage and Shawn Altizer, T.H. challenging. The Statfjord and Brent formations mic array. The paper describes the process used for Hill Associates; Geoffrey Roberts and Fred Kellow, are sand-prone, and robust mechanical sand-control implementing and verifying the technology. Devon Energy . completions are required to secure off-take rates during late-life production. Also, after 29 years of The first application of this technology on a new In determining the necessity of drill string quality production and water injection, the drilling and com- water injector delivered it 60 days ahead of schedule assurance initiatives, an operator must answer two pletion of wells through the differentially depleted with reduced costs at around US$20 million and a primary questions: 1) What is the probability of fail- formations would be challenging . In addition, the potential train wreck avoidance of US$60 million . ure? and 2) What would be the impact, financial or reservoir formations on Statfjord are substantially The observations while drilling the well strongly otherwise, of a failure event? interlayered with shale sections. This meant that indicate that the trajectory modifications done based wellbore stability issues would pose challenges. on this new method were crucial in order to get the Typically, balancing the answers to these questions well in place for successful injection. with the expense of additional quality management Initial late-life well designs were based on drilling measures has presented a challenge to onshore horizontal reservoir sections with a low ECD oil- The authors believe this is the first field application operators. However, recent increases in drilling based drilling fluid system, then displacing the well of computational geomechanics in detailed well plan- activity have dramatically changed the evalua- to brine, running sand screens and gravel packing ning in the industry. It illustrates the potential for tion process. First, supply chain pressures have the open-hole screen with a conventional water using this technology in complex field developments limited the availability of suitable drill string com- pack. During the last three years, 23 late-life produc- where production alters the in-situ stress conditions ponents and experienced personnel. Additionally, ers have been drilled and completed. This paper in such a way that other methods for predicting greater demand for all inputs of the drilling process summarizes the operator’s experiences with empha- drillabillity fails. has driven well costs to extremely high levels. sis on well design, drilling and completion tools, well Referencing the questions posed earlier, both the fluid technology and well productivity . SPE/IADC 119262 probability and impact of failure events have signifi- cantly increased. Execution Success in a Platform Drilling Technical Session: Campaign. Kolby Burmaster, Jesse Chando and To address this issue, an operator drilling in the Kenneth Vaczi, ExxonMobil. Barnett Shale region implemented an aggressive Case Histories II quality management plan to reduce risks and The challenges associated with planning and execut- expenses resulting from drill string failures. The ing an offshore extended reach drilling (ERD) proj- operator first established a baseline for NPT due SPE/IADC 119509 ect are compounded when combined with restarting to drill pipe and HWDP failures, then tracked the 60 Days Ahead of Schedule – Reducing a cold-stacked platform rig. Execution requires a changes in NPT over a two-year period . The primary Drilling Risk at Valhall Using Computational well thought-out, focused effort by the drilling team work scope of the quality consulting company was Geomechanics. Tron Kristiansen, and Roar Flatebø, to achieve the planned scope at or below the esti- to ensure that industry-accepted standards were BP Norge AS. mated cost. followed . Initial quality audits on machine shops, hardbanding applicators and inspection companies

114 January/February 2009 DRILLIN G CONTRACTOR 2009 SPE/IADC DRILLING CONFERENCE allowed formal documentation of quality gaps and team was based in Dubai to plan, manage and sup- extent. Wellbore placement was critical to ensure development of individual quality plans . port operations and an established team in Iraq to that fracture stimulation would optimize produc- follow directions from management office. tion. At the end of the two-year period, NPT due to drill pipe and HWDP failures had been reduced by 47%. Coordination of operations was done using state-of- A turbodrilling system was recommended to improve the-art communication systems, effective informa- economics drilling . Advantages included higher SPE/IADC 118898 tion reporting procedures and experienced technical mechanical horsepower, excellent directional control support on the ground. Field personnel were exten- and improved wellbore quality. The new BHA was New Washpipe Technology: Why Operators sively trained . Finally, an integrated project manage- run with excellent results, building to 90° before Should Care. Jeremy Ogg, National Oilwell Varco; ment system was created to provide clients with landing horizontally with three bits . On the next Brett Borland, ConocoPhillips. experienced project management, well engineering well, the turbodrill was optimized for directional expertise and the optimum technology for integrated response by shortening the tool, and the impreg was This paper will provide field results from a HT/HP projects to jointly create greater value in an environ- downsized to 6 1/8 in. in order to leverage available well where the application of a breakthrough tTop mentally responsible manner. The positive outcomes design options. drive washpipe technology was implemented. The are better access to technology, teamwork and an design goal of this washpipe was to significantly alliance spirit with mutually agreed objectives. Following that success, optimization of a Middle improve durability over the established industry- Atoka horizontal drilling program with turbodrill- accepted performance. Along with the field results, ing was undertaken. Previous wells required four a simple financial model will be provided that shows Technical Session: PDMs/PDCs per lateral. After analysis, engineers why the application of this new technology can yield concluded the well could be drilled with a single positive results in a relatively short period of time. Performance Drilling turbodrill BHA. The turbodrilling BHA run complet- ed the section in one run. Following this success, National Oilwell Varco has introduced a technical the new-style turbodrilling system used on the next solution that utilizes mechanical sealing technology SPE/IADC 119375 well set a state record for slimhole total footage/ developed outside the oil and gas industry, which Use of Roller Reamers Improves Drilling ROP. On the subsequent well, the section was com- has proven itself in a ConocoPhillips-led field trial Performance in Wells Limited by Bit and pleted with one turbodrill run, this time establish- with ENSCO in the North Sea. Given the demonstrat- Bottomhole Assembly Vibrations. Steven Sowers, ing a world single-run footage record for ed positive results of this application, this system is 1/ and Fred Dupriest, ExxonMobil. 6 8 in. impreg. going to lead to improved operating efficiency in the industry . Use of roller reamers has provided continuous per- SPE/IADC 119826 formance improvement in areas limited by stick-slip SPE/IADC 119815 and whirl. Performance Drilling – Definition, Benchmarking, Performance Qualifiers, BP Egypt Uses RMR on a Jackup to Solve a Top Whirl is a dysfunction characterized by lateral Efficiency and Value. Graham Mensa-Wilmot, Hole Drilling Problem. Andrew Hinton, AGR; Edvin vibration that may occur at the bit or in the BHA . Chevron ETC; Panurach Dumrongthai, Chevron ; Kvalvaag and Arthur Jongejan, BP; Kjartan Seim When whirl becomes severe, lateral vibrations cause Stephen Southland, Smith; Patrick Mays, Chevron. and Gerhard Becker, AGR. high side forces in stabilizers. Friction resulting from these side forces cause high torque at stabiliz- Challenging drilling conditions have resulted in BP Egypt used a subsea pump on the Rahamat well ers and can result in stick-slip. The operator refers increases in operational costs. Improving drilling so that engineered mud could be used to drill the to this as “coupled stick-slip” because the condition performance will help drive down costs . There are surface hole with returns to the Constellation II rig, was caused by whirl in stabilizers. Coupled stick- several positions in the industry on what constitutes (first use of RMR on a jack up). This allowed the slip is detrimental to ROP and causes premature performance drilling. In some instances the use of 26-in. surface hole to be drilled and 22-in. surface failure of bit and BHA components. When these new technology, sophisticated tools or expensive casing cemented at 1,085 m below mud line (BML) conditions exist, the replacement of stabilizers drive systems is classified as performance drilling. without problems. with roller reamers eliminates the potential for This position is severely faulted. torque-generation in the stabilizers. Consequently, Firm sand prevented a 30-in. conductor from being stick-slip does not occur until a deeper depth for a In addition to defining what performance drilling driven deeper than 51 m BML. The rig has a 40-m air given well. actually is, the importance and process of bench- gap, and the water depth is just 19 m. This resulted marking will be discussed. Drilling program success in a shoe that would support only 0.8 sg (7 ppg) fluid Whirl can also cause borehole patterns, spiraling depends on the optimization of the following perfor- back to the rig. Inhibited mud, minimum weight 1.13 ridges cut into the borehole wall. While the average mance qualifiers – footage, vibrations control, rate of sg (9.4 ppg), was needed to control the formations. diameter of the hole drilled with these patterns will penetration, durability, and directional effectiveness. Seabed returns were unacceptable for environmen- always be overgauge, it is possible for the diameter These qualifiers must be specifically ranked for tal and mud supply reasons. measured from ridge to ridge to be less than the different wells, based on their effect on operational gauge of the bit. This condition can be so severe that costs. The ranking process for the qualifiers, as well RMR installation/retrieval was mainly done off the it is not possible to trip pipe on elevators. Roller as their effects on maximization of “on-bottom” time , critical path. Equipment was installed without an reamers remove part of the ridge in such drilling NPT reduction, minimization of unexpected events ROV. RMR took returns from the conductor at sea conditions and allow pipe to be tripped on elevators will be supported with field data. Drilling efficiency level and pumped mud with cuttings back to the without excessive drag. will be defined and discussed . rig. Mud was re-circulated after treatment. This allowed good control of the mud properties. ECD This paper details the conditions where roller SPE/IADC 119421 pressure was reduced by 0.4 sg (3.5 ppg) at the cas- reamers provide benefits allowing improved perfor- ing shoe and 0.04 sg (0.3 ppg) at section TD. Mud mance. A conceptual model for coupled stick-slip is Tracking Drilling Efficiency Using Hydro- losses in coarse sands were controlled by adding provided, as well as a summary of borehole patterns Mechanical Specific Energy. Robello Samuel, LCM and fluid loss control material. The hole was that may be removed with roller reamers. Examples Halliburton; Kshitij Mohan, Faraaz Adil and Nehal drilled to the planned depth. 22-in. casing was run of wells where performance was improved as roller Patel, University of Houston. and cemented while controlling the fluid level in the reamers mitigated these conditions are also pro- annulus (and therefore downhole pressure) with vided. Different types of bits have been introduced to meet RMR. No losses were seen during these operations. the challenges of steerable and rotary steerable systems; and it is imperative that bits be utilized RMR allowed surface hole to be drilled with SPE/IADC 118809 optimally in the system. A new correlation identify- inhibitive mud and returns to the rig because RMR Beyond the Technical Limit: Turbodrilling ing inefficient drilling conditions is presented in this removed the effect of the 40-m airgap . a Paradigm Shift to World Class Horizontal paper. Mechanical specific energy (MSE) has been Well Construction. Todd Mushovic, BP; Raymond used to improve drilling rates, with mixed results. SPE/IADC 119531 Morlock, David Shuler and Dave Conroy, Smith Drilling specific energy (DSE), which is introduced Technologies. here, encompasses hydraulic as well as mechani- Remotely Managing a Project in a Volatile cal energy. DSE quantifies the amount of energy Security Environment. Hani Qutob, Waleed Wells in the Pennsylvanian reservoir are drilled required to drill a unit volume of rock and remove Asslman and Marwan Sabah, Weatherford. horizontally within extremely low permeable it from underneath the bit. DSE includes axial, tor- Ordovician layer before fracture stimulation. sional and hydraulic energy . Iraq is undergoing a period of transition , with a lack Previous attempts to drill these wells vertically with of utilities, security and basic services . Furthermore, PDCs/inserts using PDMs had proved uneconomic. Experimental and field data presented in this paper oil and gas infrastructure was in a very poor state. The challenge was to efficiently finish drilling the show that DSE can identify inefficient drilling con- Weatherford was committed to establishing their build section and land the well horizontally in the ditions. Extensive simulations have been carried business inside Iraq but decided to control and Bromide before extending the reach to its maximum out and will be reviewed. The new hydraulic term manage their operations remotely . The management

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included in the specific energy correlation is the key significant mud losses . In addition, due to high and the data compared with direct offset runs. In to correctly match the amount of energy required tectonic stresses in this region, wellbore stability the study, engineers considered bit design/materials, to drill and overcome the rock stresses. Also, this needed to be considered. turbodrill and BHA stabilization and drilling param- new term illustrates how much hydraulic energy is eter optimization. Finally, turbodrill/impreg limita- needed to drill faster when the mechanical energy To ensure safe drilling and optimum performance tions were considered. (axial and torsional) is increased. The results also for new wells, geological, petrophysical, drilling show the importance of including the bit hydraulic and completions data from the existing 16 wells in The analysis determined that turbodrilling with energy term into any specific energy analysis for the Luojiazhai Field were reviewed and analyzed impregnated bits was a n option to create savings drilling optimization. The pump-off force on the thoroughly. This paper will describe how multidis- and could effectively optimize drilling . weight on bit due to the fluid force is also included ciplinary approaches in rock mechanics, mechani- in the calculation. cal earth modeling, pore pressure prediction, and The new-style turbine/impreg BHA was run with out- MaxDrill drilling optimization can be applied to standing results. The test interval was successfully Field results reveal specific patterns for inefficient ensure that new wells be drilled faster and more drilled, eliminating multiple bit trips and reducing drilling conditions and a good correlation between safely through optimum bit selection and design, overall days. Cost savings were substantial versus the calculated DSE and the expected requirements fluid selection and mud weight design, as well as a direct offset well that experienced 38 days of for rock removal under existent conditions of stress careful well trajectory planning. trouble time through the same formations. This trial at the bit face . The practical usefulness of the theory run gives considerable strength to the hypothesis will be demonstrated with numerical examples. that impreg/turbine drilling can significantly reduce SPE/IADC 119230 risk compared with traditional BHAs used in direct Minimizing Risks, Maximizing On-Bottom offsets . SPE/IADC 119887 Drilling Time: Turbodrilling with Impregnated Drilling Optimization Study for the China Bits Improves Efficiency and Circumvents SPE/IADC 119914 Chuandongbei Luojiazhai Field. Xianjie Yi, Yoseph Trouble Time, Southern Oklahoma. Peter Langille, Harjadi, James Sabolcik, Jozina Dirkzwager, Peter ; Carl Deen and Jay Klassen, Smith Bits. Drilling an F 2-in .-in-diameter Hole in Granites

Connolly and Peng Ray, Chevron . Submerged in Water by CO2 Lasers. Toshio Drilling in the Anadarko Basin in southern Kobayashi, Japan Drilling Co .; Komei Okatsu and Chevron signed a 30-year production-sharing con- Oklahoma can present challenges like fractured Satoshi Kubo, Japan Oil, Gas and Metals National tract with China National Petroleum Corporation formations, conglomerates and other eccentric Corp ; Masahiro Nakamura, Japan Drilling Co. (CNPC) to jointly develop the Chuandongbei natural geologic phenomena. In this unpredictable drilling As part of a fundamental study of rock drilling by gas area in Sichuan, which has nearly 15% H2S con- environment, it’s difficult to optimize/refine the bit/ tent. Luojiazhai Field has been determined to be the tool and BHA selections, resulting in unacceptable/ laser irradiation, this paper describes laser drilling first to be developed . inconsistent drilling performance. of a f2-in.-in-diameter hole in granites submerged in water. In the air, molten granite produced by laser Drilling in the Luojiazhai Field by CNPC had proven To maximize on-bottom time and cut costs, an in- irradiation reflects or absorbs successively irradi- extremely challenging. Two blowouts had occurred, depth analysis was conducted to improve section ated laser beams, thereby refraining laser heat one of which killed 243 people. Formations were so economics. A consistently troublesome application from being transmitted into the rock. This absorp- hard to drill that 5-6 ft/hr ROP was considered fast. was selected where inconsistencies in the use, per- tion leads both to a temperature rise of the molten Slow drilling also led to long exposure of the open formance and dull conditions of bits in close offsets granite and a further increase in absorption of laser wellbore to water-based mud that caused tight hole were driving up field development costs. From this radiation by the molten granite, causing the rock and stuck tool problems. Natural fractures caused group, a specific interval was selected for analysis, destruction process to cease completely.

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For more info contact Anne Otten at [email protected] www.iadc.org/conferences/Middle_East_HSE.htm www.iadc.org/conferences/BBS_Workshop.htm116 January/February 2009 DRILLIN G CONTRACTOR 2009 SPE/IADC DRILLING CONFERENCE

From consideration of the lack of success in past measurements to be acquired and transmitted to laser rock drilling methods, we arrived at the idea Technical Session: surface in real time from many points along the that laser-induced mechanical forces could be string. utilized to generate a hole in rocks by laser irradia- Downhole Tools tion in water. A granite specimen was submerged Along-string annular pressure and temperature at 50 mm from a water-surface and then 10.6 mm SPE/IADC 118435 measurements provide dramatically improved vis- ibility of hole cleaning, equivalent circulating density carbon dioxide laser (CO2) beams, which have a high absorption coefficient in water, were intermittently Analysis of Hook Load Forces During Jarring. and fluid influx/loss issues at multiple points along irradiated. Kenneth Newman, NOV CTES; Ray Procter, Fearnley a well . Early use of the information delivered by this Procter Group. technology includes more effective management of The laser beams induced underwater shock waves, flow rates, mud weight, rate of penetration, string bubble formations and micro-water jet formations Twice during the last year, on opposite sides of the rotation and the use of lost-circulation material to upon bubble collapse. High-speed video observations world, drilling rigs have collapsed after prolonged significantly reduce the risk of stuck pipe, formation revealed the generation of an initial cone-shaped jarring operations. This paper documents the fracture and excessive losses. water cavity, propagation of the laser beams through analysis performed afterwards to determine if the the cavity and eventual ablation of the granite jars could generate enough force to overload the rig This paper shares and discusses previously unseen surface. The laser beams locally melt the granite structure. data from early field uses of along-string pressure surface to form small glassy beads, which are read- and temperature measurements with comparisons to ily removable by mechanical methods. Repetition of Data from the drilling logs was taken at time normally available data from bottomhole measure- this procedure demonstrated that a high-power laser intervals of 10 seconds or greater. These large ment tools. beam propagating in water can be used to generate time intervals did not allow the peak shock loads a hole in rocks. to be recorded. The rig instrumentation tends to damp out these peak shock loads. Thus, during SPE/IADC 119382 The laser beam irradiation indeed drilled the granite prolonged jarring operations, the loading can be Electric Wireline Milling – New Solutions for specimen submerged in the water. f 2-inch-in-diam- more significant than what is displayed by the rig New Challenges. Robert Joyce, Welltec, Inc. eter holes in the underwater granites were success- instrumentation. fully generated by two methods that were melting The concept of milling obstructions in wellbores, and spalling by the laser. Melting the granite to A dynamic finite element jarring analysis was done utilizing electric wireline deployed services, was generate a f 2-inch-in-diameter hole requires energy for both of these cases. This analysis calculates the introduced in 2005. Since that time, operators have almost 3 times as much as spalling the granite to loads along the drill string before and after the jar is used this technique efficiently and generate the same size hole. released. The impact load travels up and down the cost effectively. These wireline-conveyed technolo- string at the speed of sound in steel, causing spikes gies have performed well in both completion and in the surface loads. To simulate these dynamic workover programs by providing the means to drill- SPE/IADC 119491 loads, the model is run with a time interval of 100th ing out stuck valves, remove non-retrievable plugs Reelwell Drilling Method. Ola Vestavik, ReelWell of a second. This allowed the loading seen by the rig and re-establish production by removing scale. A.S.; Scott Kerr, StatoilHydro; Stuart Brown, Shell. structure to be simulated The input parameters and modeling results from both of these analysis will be The additional cost of lost, or deferred production is A new drilling method combines MPD and liner presented . always unwanted. The deployment of a traditional drilling. The method is being developed in a joint rig or coiled tubing unit to help restore produc- industry project funded by StatoilHydro, Shell and SPE/IADC 119540 tion comes with considerable cost owing to the the Research Council of Norway. The new method equipment and personnel requirements to operate. uses a dual drill string and a downhole sliding piston Along String Pressure and Temperature Consequently, operators continually look to new attached to the drill string. The sliding piston is used Measurements in Real-Time: Early Field techniques to minimize this burden. Milling on elec- for improved downhole traction and pressure control Use and Resultant Value. Monte Johnson and tric wireline is one such technique since it can be and can optionally be used in combination with an Michael Reeves, IntelliServ; Maximo Hernandez, performed in a rig-less environment. expander tool for downhole liner expansion. GrantPrideco ; Chris McCartney and Scott Allen, Oxy Oil and Gas USA. Experience has shown that each new milling chal- A full-scale test at the research rig Ullrigg in lenge requires careful study of the problem, along Stavanger successfully demonstrated the method High-speed drill string telemetry technology is with extensive testing and verification of the tech- during the fall of 2007 and spring of 2008. The tests being adopted with increased frequency into chal- nique. Every downhole scenario provides a different demonstrated the features of the new concept and lenging drilling environments around the world. In characteristic to consider. As a result, many man- its possibilities for improved pressure control and addition to allowing instantaneous transmission hours and research dollars have gone into providing drilling performance. The presentation will cover the of data between surface and measurement tools solutions for advanced milling projects. new developments and the results from the tests. located close to the drill bit, this technology enables

SPE/IADC 119382, “ Electric Wireline Milling – New Solutions for New Challenges .”

DRILLIN G CONTRACTOR January/February 2009 117 2009 SPE/IADC DRILLING CONFERENCE

This paper presents new applications for electric wireline milling. First, a sum- mary of the milling experience to date will be presented, followed by the exami- nation of some complex milling challenges through several varied case histories including the milling of isolation valves, cast-iron bridge plugs, glass plugs, nipple profiles as well as scale removal.

SPE/IADC 119420 Rotating Magnetic Ranging and Single Wire Guidance Tool Facilitates in Efficient Downhole Well Connections. Ray Oskarsen and John Wright, John Wright Co; Don Fitterer, David Winter, Anthony Nekut and Jed Sheckler, Vector Magnetics.

Downhole connections between multiple wellbores have many applications, including being an alternative to multilateral completions. An RD project was undertaken to develop and validate an electromagnetic ranging concept for enabling cost-efficient downhole connections.

After extensive testing and deeming the ranging technology suitable, an existing offshore well jacket located in southeast Asia, in 5.1 m of water and 1.3 km from shore, was identified as a candidate for field validation . In late December, 2006, a well was spudded from a nearby onshore location with the intention of drilling directionally to hydraulically connect to one of the wells drilled from the well jacket.

The objective was to prove the well-connect concept for implementation in future projects, via: achieving close intersection with the existing well, achieving hydraulic connection between the wells and to sustain sufficient flow through the connection. Two electromagnetic-ranging systems were used, namely: single wire ranging (SWR) used from <220-m MD from target and rotating magnetic ranging service (RMRS) used from a depth of <45-m MD from target. The electromagnet- ic-ranging technology facilitated in the successful intersection of the target well according to plan; by-pass within specified proximity and by-pass occurred in the correct sand.

SPE/IADC 119958 A Step Change in Drilling Efficiency: Quantifying the Effects of Adding an Axial Oscillation Tool Within Challenging Wellbore Environments. John McCarthy, Brett Stanes, Kevin Clark and Greg Leuenberger, National Oilwell Varco; Jorge Rebellon, Andergauge.

Motor steerable (MS) assemblies are used in the majority of directional drilling applications globally. However, the limitations of MS systems are often highlight- ed as trajectories become more complicated and efficient drilling performance becomes more difficult to obtain. This is a challenge as drilling efficiency contin- ues to be of top importance in the drilling of oil and gas wells.

Drilling tools that impart cyclic, axial oscillations into the drill string have been shown to extend the operating range of MS assemblies, particularly in slide- drilling mode. Based on the successes of over 5,000 field runs, the results appear clear, though intuitively there could be problems associated with adding axial vibration into the drill string. Historically, measuring the actual forces trans- mitted by the axial oscillation system has been a challenge as most downhole measuring devices record at sample rates significantly lower than the operating frequency of the oscillation tool. In addition, these tools often do not have the number of data channels required to fully describe the downhole dynamic envi- ronment. Furthermore, variations in bit type, bottomhole assembly configuration, drilling parameters and formations make detailed comparisons difficult.

This paper will compare a number of field runs with and without an axial oscil- lation system and will quantify the actual downhole accelerations caused by add- ing the oscillation system to the drill string.

SPE/IADC 118328 A New Azimuthal Gamma at Bit Imaging Tool for Geosteering Thin Reservoirs. Jason Pitcher, Halliburton; Daniel Schafer, BP; Paul Botterell, Halliburton.

A new azimuthally-sensitive gamma-at-bit imaging tool has been designed for use in geosteering and to provide gamma measurements very close to the bit while drilling. It uses binned azimuthal measurements from four scintillation gamma-ray detectors spaced at 90° around the collar. Continuous image logs are recorded and telemetered to the main LWD string and ultimately to the surface whether the tool is sliding or rotating. When rotating, data can be recorded in quadrants, octants or hexadecants. When sliding, quadrant data is recorded. Typically, quadrant data is sent to the surface in real time, though other data densities are possible .

This paper discusses the tool and its incorporation in an adjustable bent hous- ing motor. Methodology and experiences are discussed for transmitting the data back to the main LWD string and to the surface A field example is presented to demonstrate the geosteering capabilities of this system in a thin reservoir within a complex geological environment .

118 January/February 2009 DRILLIN G CONTRACTOR