TheThe PracticalPractical ApplicationApplication && InnovationInnovation ofof CleaningCleaning TechnologyTechnology forfor CondensersCondensers

By George Saxon, Jr., and Andy Howell

aintaining clean con- potentially resulting in huge economic and corrosion should be carefully moni- denser tubes is of vital penalties in unit outages and equipment tored, and the condenser cleaned at optimal importance to reliable, repair and/or replacement. Measures to intervals. efficient power plant remove foulants from condenser tubes can operation. Ideally, foul- be a very minor price to pay in terms of the Condenser Tube Ming would be avoided entirely; however, overall picture. The principal modes and types of foul- this is rarely the case. Condensers may Options for cleaning foulants off-line ing on the interior of condenser tubes are: become lightly fouled with soft organic include chemical (acid or chelate dissolu- I Deposition or particulate deposits, or can be severely scaled with tion) and mechanical means (metal or plas- I Scaling or crystallization hardened minerals. The probability of suc- tic scrapers, brushes, high pressure , I Microbiological cess in cleaning the condenser is depend- etc.). On-line preventive measures also I Debris or macrofouling ent on the selection of the appropriate exist, including chemical treatments (scale cleaning technology under the specific and corrosion inhibition, dispersants, bio- I Corrosion and corrosion products fouling conditions. Early identification of cides) and continuous recirculation of In most cases, fouling is not due to a fouling characteristics and a fundamental mechanical cleaners of a variety of types. A single mechanism; however, in many situ- knowledge of cleaning system capabilities close look will be taken at the use of metal ations one mechanism will be dominant. are essential in determining the most scrapers for off-line cleaning, as this has Fouling tends to increase over time, with effective cleaning technology, as well as been a reliable and effective technology for the rate of increase being very site-speci- the frequency of cleaning required. several decades, with scraper designs con- fic. Recognizing this, the Tubular Two major problems result from sub- tinually evolving to meet the needs of vari- Exchanger Manufacturers Association1 stances on the interior tube surfaces: 1) ous fouling situations. Metal scrapers have has recommended that designers of heat Loss of ; and, 2) Under-deposit distinct advantages over other tube cleaning exchangers include an allowable fouling corrosion. Internal tube fouling is nearly methods in certain scenarios. The most resistance in their calculations, in order always detrimental to heat transfer, thus effectively designed scrapers are sized to that some fouling can be tolerated before reducing the efficiency of steam condens- closely match tube interior dimensions in cleaning becomes necessary. Heat ing, resulting in a lower vacuum (higher order to clean near to the base metal. Exchange Institute standards2 also include pressure) and less efficient steam turbine Scrapers are propelled rapidly through the some fouling in their requirements for operation. In severe cases, poor vacuum tubing (at 20 ft/sec) by pressurized water. steam surface condensers. Although these conditions in the condenser can reduce elec- Occasionally when difficult deposits and allowances tend to mask losses of efficien- tric-generating capacity by more than 50 corrosion products are encountered, repeat- cy, fouling still may have an impact on percent. Under-deposit corrosion of tube ed passes of the scrapers may be used to under-deposit corrosion; most corrosion metal can result in through-wall leaks, per- ensure optimal cleaning. Innovation of new problems on the interior of condenser mitting ingress of cooling water into high- tube cleaner designs may also be required tubes result from tube fouling. Thus, purity steam condensate. Dissolved contam- to enable effective cleaning of unique determining when to clean often requires inants in cooling water (which may be very deposit scenarios, or when existing technol- striking a balance between tolerable effi- concentrated in seawater or recirculating ogy is inadequate. Since condenser fouling ciency loss and providing protection from cooling towers) can cause major damage to can have such a dramatic impact on cost- corrosion. A model of under-deposit cor- boiler tubing and steam turbine materials, effective power plant operation, deposition rosion3 is shown in Figure 1.

AUGUST 2005 | ASME Power Division Special Section ENERGY-TECH.com I 19 COOLING WATE R OH- H+ Cl- H+ OH- Cl- O2 O2 Cl- Cl- - - O Cl C l 2 O2 P OR OUS DEP OS IT ME TAL e- OXIDE e- H+ Cl- TUBE MATE R IAL Deposition or particulate fouling Deposited material is fine-particulate S HELL S IDE debris that settles on the tube surface due Figure 1. Model of under-deposit corrosion. to gravity under low-flow conditions. This debris may be natural sediment (i.e., river silt), biogrowth (i.e., algae), coal dust water is exceeded, and precipitation the substrate is more difficult at higher from plant operations transported to occurs directly on tube surfaces. Some velocities. Conversely, low velocities (sim- source water, or crystalline solids precipi- common cooling water constituents form ilar to those that may support fine particu- tated as particulates in a scales that precipitate preferentially under late deposition) are conducive to bio- basin (i.e., calcium carbonate, silicates, higher temperature conditions (calcium growth. Biofilms contain a considerable phosphates, sulfates, etc.). Deposits may carbonate, calcium phosphate); therefore, amount of entrapped water, and when dry, form inconsistently over a tube surface, formation of scale on warm tube surfaces may appear to be of minimal significance; primarily occurring at the bottom of the is promoted. Such scaling is also more however, water is a relatively good insula- tube due to gravity settling. likely to occur on hotter tube surfaces tor of heat, so even thin biofilms can have Normal recommended flows through (towards the condenser outlet). a major impact on heat transfer. In one condenser tubes (minimum seven feet per When condenser tubes are scaled it is incident, a station lost over 50 percent of second) should be adequate to prevent the usually a widespread occurrence, and very generating capacity due to backpressure settling of particulates; however, a con- detrimental to heat transfer. Even a thin problems resulting solely from a biofilm6. denser with an average flow representing layer of scale can cause a major reduction In many cases, biofilms will entrap fine 7 fps may have areas or specific tubes in heat transfer; for instance, manganese, particulates, which may further reduce with much lower flow rates. For example, silica, and calcium carbonate scales have heat transfer. inadequate circulating water pumping may been reported to cause losses in output As mentioned previously, certain types not entirely fill an inlet waterbox, so that capacity of 20 to 25 megawatts4. Scale of bacteria produce corrosive metabolic intermittent and partial flow can occur in can also provide sites for local under-scale by-products (sulfate-reducing bacteria, upper tubing. Partial blockage will also corrosion (Figure 2). Inconsistently pres- SRBs); others (iron-oxidizing) may actu- cause reduced flow through tubes, which ent scale, with areas of scale-free surface ally consume base metal. Corrosion by can result in considerably increased partic- due to either loss of existing scale or bacteria is usually not a serious problem ulate settling and accumulation down- inconsistent formation, is particularly except in cases where stagnant conditions stream of the blockage. detrimental; erosion-corrosion can result exist (under deposits or scale, or off-line The most serious problem resulting in brass tubes due to local flow during unit outages). One exception is from deposition in condenser tubes is turbulence5 (Figure 3), and the likelihood manganese pitting of stainless steel, which under-deposit corrosion. This can be a of damage from differential concentration occurs on-line with a thin manganese serious problem even when heat transfer corrosion cells may also be enhanced. The oxide scale that is believed to be deposited efficiency is only a minor concern, most comprehensive removal of scale is by micro-organisms (Figure 4). because the amount of tube surface con- generally required. taining deposits that stimulate under- Debris and/or macrofouling deposit corrosion can be relatively small. Microbiological fouling Macrofouling of the condenser inlet Corrosion occurs primarily because of the Bacteria present in natural will tubesheet and tubes can occur by any sub- electrochemical potential differential commonly form a thin biofilm on con- stance whose size is close to, or greater between the tube surface beneath the denser tube surfaces. Recirculating cool- than, tube internal diameter. Rocks, con- deposit and the adjacent general (clean) ing water (cooling towers) is typically crete debris, cooling tower materials tube surface. Additionally, corrosion is treated with biocidal chemicals, such as ( fill, wood), chunks of ash, large often enhanced by the action of bacteria bleach, chlorine gas, or organic biocides. pieces of rusted steel, coal, windblown within the deposit, which can produce cor- These may be fed continuously or inter- debris (paper trash, leaves, or other vege- rosive metabolic constituents. Because of mittently (e.g., two hours daily), and are tation), aquatic animals (crayfish, fish, this phenomenon, it is necessary to keep very effective in limiting the growth of clams), and any other substance that tubes as clean as is practical. populations. However, enters the circulating water can obstruct once a biofilm gains a foothold, biocides cooling water flow. Scaling or crystallization fouling may not be effective for film removal. Partial flow blockage of condenser Scale occurs when the saturation point Biofilm development is inversely related tubes can occur when a tube inlet is par- of dissolved constituents in the cooling to flow velocity; attachment of bacteria to tially covered by debris (e.g., a piece of

20 I ENERGY-TECH.com ASME Power Division Special Section | AUGUST 2005 Figure 2. Pitting under scale in stainless Figure 3. Erosion-corrosion around deposits. steel tube. plastic), or when an object lodges within a circulating water systems can permit entry pitting. Unfortunately, normal operating tube (e.g., a rock or piece of wood). Two of debris after the screens, or debris may conditions can be damaging to this film. damaging effects can result: 1) Slower originate downstream of the screens (i.e., Copper oxides will continue to grow in flow through the tube will permit fine par- deteriorating concrete tunnels or waterbox oxygenated water of high conductivity, ticulates to accumulate and settle; and, 2) epoxy coatings, rust chunks). and a very thick outer layer of porous Local flow around the lodged item may be cupric oxide (CuO) can develop. This high, causing erosion-corrosion (primarily porous, non-protective oxide disturbs the a problem for copper alloys). Screens are Corrosion fouling cuprous oxide film and concentrates cor- employed prior to the condenser, with Properly cleaned copper alloy tubes in rodents that can attack and pit the base mesh size selected to prevent debris larger waters of low corrosivity are not normally metal. Thus, cupric oxide not only reduces than tube internal diameter from traveling susceptible to pitting.7 Copper alloys pas- heat transfer, but can also accelerate cor- to the waterbox. However, clogged screens sivate by forming a protective cuprous rosion. Where thick cupric oxide films may overflow, corrosion may create wider oxide (Cu2O) film on the surface. This develop, they must be removed regularly openings in the screens, elongated objects basic protective film is non-porous, very to prevent pitting and extend tube life. may pass through screens and lodge side- thin, and transfers heat efficiently. Under normal circumstances, stainless ways on tubesheets, and sometimes open Undisturbed, this film keeps the tube from steels and titanium form very thin passive

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AUGUST 2005 | ASME Power Division Special Section ENERGY-TECH.com I 21 World Tribology Congress III September 12-16, 2005 Washington, D.C., USA www.conferencetoolbox.org/wtc05/ The Tribology Division of ASME International and The Society of Tribologists and Lubrication Engineers (STLE), in association with the International Tribology Council (ITC), invite you to participate in the World Tribology Congress III. This international event will bring together tribologists, scientists, researchers, and engineers from around the globe including participants from over 33 cooperating associations. oxide films that neither inhibit heat trans- mentioned, screens are installed to block foulants, the jet nozzle must be moved fer, nor promote corrosion. large debris from reaching the condenser. along the tube slowly, and the time Settling ponds and/or clarifiers remove required to clean a can be Prevention of particulate and some dissolved con- excessive. Great care must be taken to Tube Interior Fouling stituents. Filtration systems, such as sand avoid damaging the tubesheet, tube coat- filters, can also be employed to remove ings, or inlet-end inserts, which may be Suitable approaches exist for address- fine particulates, on either a full-flow or present. Otherwise, the successful removal ing routine condenser tube fouling prob- sidestream partial flow basis. A number of of fouling deposits may be accomplished lems. However, applying preventive meas- systems have been developed which send at the cost of new tube leaks or increased ures for all possible fouling scenarios cleaning objects such as sponge balls, tubesheet corrosion, only recognized after would be cost-prohibitive, particularly for brushes, or plastic scrapers through tubes the unit has been brought back on-line. those issues a station considers itself with cooling water flow, theoretically wip- Molded plastic cleaners (pigs) are quite unlikely to encounter. Chemical and ing tubes clean. popular for some light silt or microbiolog- mechanical preventive approaches are ical film applications. Brushes can also be commonly utilized. Off-Line Mechanical used to remove these soft deposits. Brushes are also useful for cleaning tubes Chemical treatment Cleaning Options with enhanced surfaces (i.e., spirally Several chemicals, often in combina- While cleaning and preventive meas- indented, or finned), or those tubes with tion, are used to control condenser tube ures for condenser tube fouling can be thin wall metal inserts or epoxy type inlet fouling. Chemicals are primarily utilized performed on-line, the remainder of this coatings. with recirculating cooling towers, article focuses on cleaning technology innovations and procedures that are per- because: 1) The concentration of dissolved Metal scrapers constituents is significant, increasing the formed off-line; specifically, mechanical threat of scaling and corrosion; and, 2) cleaning options, which are the most fre- With harder types of deposits, calcium Once-through cooling systems often dis- quently chosen, most generally applicable carbonate (calcite) being a notable exam- charge directly into a river, lake, or ocean and effective, and fastest cleaning meth- ple, metal cleaners of various designs have with chemicals restricted in the effluent. ods available. been developed for effective removal. The 8 Some chemical treatment methods com- Saxon and Putman addressed the ben- spring-loaded blades of the metal cleaner monly used are: efits of mechanical cleaning for improving are an essential element in the success of I pH control plant performance and, consequently, the technology. The use of spring-loaded I Scale inhibitors reducing CO2 emissions. The conclusions tube cleaners was identified as a best maintenance practice by Putman and I Dispersants are straightforward: Off-line mechanical cleaning is especially useful where fouling Walker9.The blades are mounted on a I Biocides problems exist that are too severe to be spindle (Figure 5), and one end of the I Corrosion inhibitors handled by any of the other methods. spindle has a serrated plastic disk that Obviously, the tool selected must be the allows a jet of water to propel the cleaners Mechanical fouling prevention most appropriate for removing a particular through a tube with greater hydraulic effi- A number of approaches have been type of deposit. ciency. The water is directed to the tube developed to prevent condenser tube foul- Although the use of high-pressure being cleaned by a water gun, and is ing by mechanical means. As previously water can be effective with certain (Continued on page 24.)

Tube Cleaning Deposits Wall B lade

Figure 4. Manganese-induced pitting in Figure 5. Tube cleaner in action. (Figure courtesy of Conco Systems, Inc.). stainless steel tube.

22 I ENERGY-TECH.com ASME Power Division Special Section | AUGUST 2005 To contact this company enter 04988 on infolink at Energy-Tech.com or see the Ad Index page 44 ple, in order to provide the blades with more circum- ferential coverage of the tube surface, a new scraper design was intro- duced (Figure 6). The increased contact surface provided by the greater Figure 6. Hex Cleaner. Patent Figure 7. Cal Buster. Patent number of blades was No. 0698423. (Photo courtesy No. 5153963. (Photo courtesy found to be more efficient of Conco Systems, Inc.). of Conco Systems, Inc.) in removing tenacious deposits such as those consisting of various forms of manganese. excessively, and sometimes become hard- delivered by a portable pump. Water pres- Another development involved a tool for er. In such cases, for example, it may be sure of 300 psig is most effective for pro- removing hard calcite deposits, which were necessary to acid clean, followed by pelling the cleaning tools through the sometimes found to be difficult to remove cleaning with mechanical cleaners or tubes at their design travel speed of 10- to in a timely manner, even by acid cleaning. high-pressure water to remove any 20-feet per second. The use of water pres- This cleaner is shown in Figure 7, and con- remaining debris. Tube cleanliness can sure also prevents the cleaner’s exit veloc- sists of a teflon body on which are mounted then be maintained by regularly scheduled ity from rising above a safe level. Some a number of rotary cutters. These are placed off-line cleaning. other cleaning systems use air or a mix- at different angles around the body, which is ture of air and water to propel the cleaner, fitted with a plastic disk similar to those but air pressure is compressible and dan- Effect of metal scrapers used to propel other cleaners through tubes. gerous to use. Since the pump is usually on tube surface Used on condenser tubes that had accumu- mounted on a wheeled base plate, the sys- lated a large quantity of very hard deposits, One perceived drawback of using tem can be conveniently moved from unit Stiemsma, et.al.11, described how cleaners metal scrapers to clean condenser tubing to unit within a plant, or even moved to of this type removed 80 tons of calcite is their effect on tube metal, including another plant. material from a large surface condenser. It concerns over incompatibility of the car- Another advantage of using water for has now become a standard tool whenever bon steel scrapers with various tube metal tube cleaner propulsion is that the material hard and brittle deposits are encountered. alloys, and the possibility that base metal removed is rinsed out, and can be collect- Hansen and Saxon12 demonstrated the prac- might be removed by the scraper digging ed in a plastic container for later drying tical use of this tool for removing scale into the tube wall. Additionally, many and weighing to establish the deposit den- from stainless steel condenser tubes. plant operators are concerned that metal sity (g/m2), followed in many cases by Boroscopic photography shows the effec- scrapers will remove protective oxide laboratory analysis of the deposit. tiveness of this cleaning tool in Figure 8 and coatings from tube surfaces, thus exposing Most metal cleaners are designed to Figure 9. base metal to accelerated local corrosion. have a controlled spring-loaded cutting Additional developments for the With cleaners that have been properly edge; however, if effective deposit removal of manganese dioxide, iron oxide, designed and carefully manufactured, loss removal is to be the result, the dimensions and silica deposits include the stainless of base metal is very minor. Indeed, of the cutting surfaces have to be closely 13 steel brush, which has over 1,000 contact Hovland, et.al. , tested such carbon steel matched to the internal diameter of the points per brush. Actual aluminum brass cleaners, manufactured by Conco tube being cleaned. This not only tube samples with iron and manganese Systems, Inc., by repeatedly passing them improves the peripheral surface contact, deposits were examined in the “as found” through 30-foot long 90-10 CuNi tubes. It but also ensures that the appropriate and “as cleaned” condition (Figure 10). was found that after 100 passes of these spring tension will be applied as the clean- After one pass of the stainless steel brush, cleaners, wall thickness reduction was er moves through the tube (Figure 5). The the cleanliness factor for the tube from only between 0.0005" and 0.0009" (12.5 effective life of cleaners with this design waterbox A went from 83.3 percent to and 23 µm). At this rate, extrapolating the can be as high as 12 tube passes. 91.5 percent, and from 73.6 percent to worst-case removal from this series of In practical experience, Kim10 found 94.1 percent in the tube from waterbox B. tests for a 0.049" wall thickness, it would that annual off-line mechanical tube clean- The experience gained from using take about 2,700 passes of a cleaner per ings using metal scrapers was effective in these techniques has allowed the cleaning tube, or roughly 1,000 years of annual reducing the corrosion rate, retarding pit- duration to be forecast with confidence condenser cleanings to result in a critical ting, and increasing unit availability, and cleaning to be performed on schedule. reduction in tube wall loss. reversing a trend of increasing tube leaks For instance, a normal crew of four tech- Regarding exposure of base metal to and plugging. nicians can clean 5,000 tubes during a 12- accelerated corrosion due to removal of a hour shift. Clearly, the number of tubes protective oxide layer, no evidence of this Innovations in cleaning cleaned in a day could rise with an scenario has been produced. In fact, where technology increase in crew size, limited only by the protective oxide is removed, it is rapidly As a result of an innovative research availability of adequate space for the crew re-formed upon exposure to oxygenated program organized to resolve problems to work effectively. water, with no detrimental effects. encountered in the field and to develop All off-line cleaning methods may new products where existing equipment sometimes require additional deposit Metal scrapers on stainless steel was found to be inadequate, new tube removal assistance, especially where the Most stainless steel condenser tube cleaners have been developed. For exam- deposits have been allowed to build up installations have been composed of the

24 I ENERGY-TECH.com ASME Power Division Special Section | AUGUST 2005 Anderson16 on stainless steel tubes that steel debris would oxidize preferentially to had been cleaned with carbon steel the base metal. mechanical scrapers. No transfer of car- bon steel onto the stainless steel tube sur- faces was observed, and this has been the Selecting a Cleaning Procedure common experience. There is no possibili- Regardless of the tube material, the ty of galvanic corrosion of the stainless most effective way to ensure that tubes steel as embedded carbon steel particles achieve their full life expectancy and max- would corrode preferentially. After such imum heat transfer efficiency is to keep particulates are oxidized to iron oxide they them clean. Each time the tube deposits, should be removed, similar to any other sedimentation, biofouling, and obstruc- particulate fouling. It is well known from tions are properly removed, the cleaned the literature and in practice that if 300- surfaces should be returned as close to 304 or 316 alloys. They were first series stainless steel tubes are not kept bare metal as possible. This restores opti- installed for surface condenser applica- clean, deposits such as naturally occurring mal heat transfer and essentially supplies tions over 45 years ago, and have seen iron oxide, manganese oxide, calcium car- the tube itself with a new life cycle, as many routine cleanings with both carbon bonate, and bacterial accumulations are protective oxide coatings quickly rebuild steel and stainless steel scrapers. As prone to cause pitting and crevice corro- themselves to re-passivate the cleaned described by Saxon14 and later Putman15, sion. Stainless steel condenser tubes must tube. it is clear that these tubes, as with other be kept clean, and properly designed While most existing foulants can be alloys, frequently require cleaning. metal scrapers, either carbon steel or removed by either chemical or mechanical While concerns over material incom- stainless steel, are an effective option. means, selection of an optimal method is patibility with metal scrapers and stainless While this section has focused on 300- generally based on the type of foulant and steel tubing have been expressed, in prac- series stainless steel tubes, similar consid- the cost of the technique. Putman17 tice there has been no evidence of carbon erations would apply to the possible described the important criteria in select- steel particles from properly designed embedding of carbon steel scraper materi- ing an appropriate cleaning procedure: the mechanical scrapers embedding into stain- al in other common tube alloys, such as selected cleaning procedure should less steel tubes. Tests were conducted by titanium and copper alloys—the carbon remove the particular deposits that are

A Water Box As Found Tube A Water CFAs F83.3%ound Box Tube CF 83.3%

Cleaned Tube SSTBCleaned 1 Pass Tube CFSSTB 91. 5%1 Pass CF 91.5%

Figure 8. Stainless steel condenser tube with calcium carbonate scale. B Water Box As Found Tube B Water CFAs 73.6% Found Box Tube CF 73.6%

Cleaned Tube SSTBCleaned 1 Pass Tube CFSSTB 94.1% 1 Pass CF 94.1%

Figure 9. Stainless steel condenser tube with calcium carbonate Figure 10. Aluminum brass tubes tested for manganese and iron deposit scale removed. removal.

AUGUST 2005 | ASME Power Division Special Section ENERGY-TECH.com I 25 7 Saxon, G.E., “Copper Alloy Tube Cleaning,” TPT-, Vol. 1, No. 1, Essential Courses for Engineers & September – October, 1990, Publ. Other Technical Professionals 2005 INTRAS Inc., Danbury, CT., pp. 28-30. Calendar of Events 8 Saxon, G.E., Jr., and R.E. Putman (2003), “Improved Plant Performance October 24-28, 2005 - Houston Marriott West Loop-Galleria and Reduced CO2 Emission Through 1750 West Loop South • 800.613.3982 State-of-the-Art Condenser Cleaning and Air-Inleakage Detection” Pressure Vessels, Piping & Boilers Proceedings, ASME IJPGC 2003, Oct. 24-26: Practical Welding Technology Atlanta, GA, June 16-19, cd. Oct. 24-26: Section VIII, Division 1, Design & 9 Putman, R.E. and Walker, R., “Proper Fabrication of Pressure Vessels Maintenance Practices Involving Oct. 24-26: ASME B31.1 Process Piping Oct. 24-28: Section VIII, Division 1- 5 Days Condenser Cleaning and In-leakage present as effectively as possible, and ren- Oct. 27-28: Inspection, Repairs, and Alterations of Inspection,” Proceedings of the der the unit out of service for the minimum Pressure Vessels International Conference on Power amount of time. Some other major consid- Station Maintenance 2000, Oxford, Fluids & Heat Transfer erations in the selection process are: England, The Institution of Mechanical Oct. 24-26: Flow Induced Vibration with Failure I Removal of obstructions Engineers (IMechE), Sept. 18-20, 2000, Analysis Considerations I Removal of corrosion product pp. 161-170. Oct. 24-27: Pump & Valve Selection for Optimum I Surface roughness 10 Kim, D.S. and Putman, R.E. System Performance Oct. 27-28: Thermal Treatment Technologies (1993),“The Management of Condenser Conclusion Tube Pitting at #2 Yong Nam Thermal Design, Manufacturing and Materials Amidst a marketplace replete with Power Plant to Improve Unit Oct. 24-26: Fracture Mechanics: Approach to Life numerous cleaning and service options for Performance and Availability,” Prediction removing fouling from the interior of con- Proceedings of IJPGC, Kansas City, Oct. 24-25: Fasteners: A Designer’s and User’s denser tubes, site engineers and staff must October 1993, PWR-Vol.23, pp.43-48. Guide 11 Steimsma, R.L., Bhayana, G.K. and Oct. 26-27: Design & Behavior of Bolted Joints choose maintenance practices that will Oct. 28: Design of Bolted Flange Joints help improve performance while protect- Thurston, R.D., (1994), “Performance ing from corrosion, ensuring the integrity Enhancement by an Innovative Tube Engineering Management of their equipment will not be compro- Cleaning Application,” Proceedings of Oct. 24-26: Project Management for Engineers mised. Innovative techniques or proce- IJPGC 1994, Phoenix, AZ, American and Technical Professionals dures may be required. Interim gains in Society of Mechanical Engineers, Oct. 27-28: Computerized Maintenance performance can be achieved while main- (ASME) New York, PWR-25-1994, pp. Management Oct. 27-28: Project Management Certification taining the long-term efficacy of a given 7-11. 12 Hansen, J.T and Saxon,G.E., Jr., Exam Preparation unit, so long as the cleaning technology Oct. 27-28: Mechanical Tolerancing Using Six applied is sound and site-specific. ET “Improving Condenser Efficiency with Sigma Innovative Scale Removal System Oct. 27-28: Resource Management References Technology,” Proceedings of Power 2004: ASME Power 2004, Baltimore, This is a partial listing. Please contact ASME for 1 TEMA (1988). Standards of the Maryland, March 30 – April 4, 2004. additional dates and details: 800.843.2763 or Tubular Heat Exchanger Manufacturers 13 Hovland, Alan W., Rankin, Drew A., www.asme.org/education Association, 7th ed., Tarryton, NY. and Saxon, Edward G., “Heat 2 HEI (1998). Standards for Power Plant Exchanger Tube Wear by Mechanical Heat Exchangers, 3rd Edition, Heat Cleaners,” Proceedings of The Joint focus of his work has been on problem Exchange Institute, Cleveland, OH. Power Generation Conference, 1988, solving and corrosion issues. He holds 3 Putman, R.E., Steam Surface Philadelphia, PA, Sept. 25-29, 1988. B.A. and M.S. degrees in chemistry from Condensers: Basic Principles, 14 Saxon, G.E., Stainless Steel Tube the University of Missouri-Columbia. Performance Monitoring, and Cleaning, Conco Bullets, Vol. 3, Issue Maintenance, 2001 ASME Press, New No. 7, 1988. pp 1-2. George Saxon, Jr., is Vice President of York, NY, pp 172-174, 183,184. 15 Ibid, Putman, R.E., 2001. International Sales and Marketing at 4 Saxon, G.E.,Jr., R.E. Putman, and 16 Anderson, Susan et. al., “Mechanical Conco Systems, Inc. Conco delivers exclu- R.Schwarz (1996), “Diagnostic Manganese Dioxide Removal in sive technologies for condenser tube Technique for the Assessment of Tube Stainless Steel Condenser Tubes,” EPRI cleaning, leak detection, and eddy current Fouling Characteristics and Innovation Service Water Systems Cleaning testing to the power generation industry. of Cleaning Technology,” Proceedings, Technology Seminar, Palo Alto, CA, He is the Vice Chair of the ASME Heat EPRI Condenser Technology February 21-22, 1990. Exchanger Committee and has served on Conference, Boston, August, pp 14-1 to technical advisory committees for Electric 14-14. Note: This article is edited from a paper sub- Power Research Institute (EPRI). He is a 5 Howell, A.G., and Schwarz, R.C, mitted at ASME Power 2005 (PWR2005- member of the American Society of Non “Erosion-Corrosion in Copper-Alloy 50173), by the same authors. Destructive Testing (ASNT) and is a pub- Condenser Tubes, Proceedings, EPRI lished author and speaker. Condenser Technology Conference, St. Andy Howell has 23 years with Xcel Petersburg, FL, September 1993. Energy & its predecessors in the power Contact the authors via editorial@magel- 6 Howell, A.G., Internal Report, 2004. plant chemistry organization. The primary lanpubs.com

26 I ENERGY-TECH.com ASME Power Division Special Section | AUGUST 2005