UBO & MPD Glossary December 2011 Aniline Point – The aromatics content of a hydrocarbon A. mixture. Abnormal Pressure - Reservoir pore fluid pressure that Annulus Friction Pressure (AFP) – Difference is not similar to normal saltwater gradient pressure. The between bottomhole pressure and choke pressure due to term is usually associated with higher than normal friction; a function of flow rate, hole geometry, surface pressure, increased complexity for the well designer and roughness, fluid properties. an increased risk of well control problems. Abnormal – American Petroleum Institute. pressure gradients exceed a 10-ppg equivalent fluid API density (0.52 psi per foot). Gradients below normal are API Gravity - arbitrary measurement of density adopted in called subnormal. 1921 by the American Petroleum Institute and the Bureau Absolute Pressure - pressure measured with respect to of Standards. zero pressure; the sum of atmospheric pressure and gauge Apparent Power - combination of real and reactive pressure. power. Absolute Temperature - temperature measured with Apparent Viscosity - Slope of the shear stress versus respect to absolute zero, in degrees Rankine or degrees velocity gradient for a fluid. For Newtonian fluids, the Kelvin. apparent viscosity equals the absolute viscosity. Absolute Viscosity - dynamic relationship between a Aromatics – Ring group chemical structure. Most force and the fluid motion. common are benzene, toluene, and xylene. Absolute Zero Temperature - temperature that B. prevents molecular motion. Back Pressure Valve - A flow control valve to provide - rate of change in velocity. Acceleration backflow control when running or pulling a string. Active data - continually updated data, based on latest Backup – Redundant equipment available to complete an operational data. operation in the event the primary equipment fails. Actuators - part of a control system, which regulates speed, Balance - steady state of flow line or vessel has three critical power, valve position, etc. to match a set point. characteristics: a) a single flow rate from node to node; Adiabatic – process that is at constant temperature without (b) an even pack throughout the system; and (c) loss or gain of heat. approximately equal volumes entering and leaving the line Adiabatic Efficiency - ratio of theoretical temperature or vessel. increase to actual temperature increase; a measure of the Ball Check Valve - A valve permitting flow in one work done by a compressor that is not lost as heat. direction only by lifting a spring-loaded ball off its seat. Adapter Spool - connects blowout preventers of different Valve opens when pressure differential acts in the desired sizes or pressure ratings to the casing head. flow direction. The valve seals by forcing the ball tightly Adequately Ventilated Area – is an area having a against the seat when a pressure differential acts opposite natural or artificial ventilation system to prevent the the desired flow direction. accumulation of gases to an explosive level. API Recommends Ball Valve - ball-shaped valve with conduit port and 90 12 air volume changes per hour or 1.5 CFM per square foot of degree rotation. Normally full port with minor pressure floor area whichever is greater. loss. Adjustable Choke - A choke with a conical needle and Barrel - unit for volume of oil, the standard barrel contains seat vary the rate of flow. See also chokes 42 gallons. Aeration – injecting gases in varying amounts into a fluid.. Base Load - minimum load. Aftercooler - Heat exchanger used post compression to Battery - Equipment used to process or store crude oil reduce gas temperatures. from one or more wells. Air Cutting - inadvertently incorporating and dispersing Bernoulli's Equation - relates to the total energy at two air (mechanically) into a drilling fluid system. points in an incompressible liquid flowing at a steady rate. Anchor - Device used to secure items of equipment, Bernoulli's Principle - liquid pressure is inversely important in the context of UBD where vibration is a proportional to the square of liquid velocity. factor or concern. Best Efficiency Point (BEP) - point on the speed- Affinity Laws - equations that correlate the relationship of efficiency curve where the pump or compressor is head, speed, impeller diameter, flow, and efficiency for operating at its highest efficiency. turbo machinery. Bleed Off Line – Component of pressure containment Ambient Temperature - temperature of the system on a snubbing stack to drain cavity and reduce surroundings. trapped wellbore pressure. American Standard Code for Information Block Valve - valve that is either open or closed; used to Interchange. (ASCII) – A different byte represents isolated equipment or pipeline sections. each number, letter, symbol and punctuation mark. Blooie Line – Large diameter flow line for air or gas Replaced by Unicode. drilling that diverts the flow of air or gas from the rig into a pit ASME – American Society of Mechanical Engineers. area. ANSI – American National Standards Institute. Blow Down - To vent off gas in a well. UBO & MPD Glossary December 2011 Blowout - A condition when hydrocarbon containment of a Cathodic Protection - type of protection that prevents wellbore is lost. Oil and gas 'blow wild' at the surface. external corrosion; it consists of setting up a current Blowout Preventers (BOPS) - High-pressure wellhead around the line or vessel to reverse the flow of electrons valves designed to shut off the uncontrolled flow of and thus inhibit corrosion. hydrocarbons. Cavitation – is when the fluid pressure in the line or vessel Booster Pumps - mechanical devices used to raise the drops below the vapor pressure of the liquid being head of liquid to meet minimum head requirements of the transported resulting in the rapid formation and collapse main line pumps downstream. of vapor bubbles in a flowing liquid. Borehole Pressure - Total pressure exerted in the Cavitation Index - ratio of pressure drop across the valve wellbore by a column of fluid and /or backpressure divided by the difference between the inlet pressure and imposed at the surface. the vapor pressure of the liquid. Valve selection to ensure Brake Horsepower (BHP) - effective (useful) operation above the cavitation point is the primary use. horsepower developed by an engine brake. Cellar - A pit beneath the rig floor to provide additional Branch - See lateral. height between the rig floor and the wellhead and to allow the installation of the bops / rotating head / rotating diverter, rat - British Thermal Unit; the amount of heat required to BTU hole mouse hole etc. raise the temperature of one pound of water one degree - uses a rotating impeller to Fahrenheit. Equivalent to 252 calories or 778.2 foot- Centrifugal Compressor pounds. increase the pressure of a gas. Bubble Flow - A multiphase fluid-flow regime. The gas Centrifugal Pump - rotating machine device that uses phase exists as bubbles distributed through the liquid centrifugal force to convert mechanical energy into phase. Where the bubbles coalesce and form a less pressure or head. uniform distribution of the gas phase, slippage will occur Centrifugal/Gear Pump - pump used to draw the between the phases. crude oil at a constant pressure and flow rate. Bull Heading - The practice of pumping into a closed – in Centripetal Force - pulls or pushes an object towards the well without returns, or forcing fluid down a well under center of a circular path. pressure. Certified – components manufactured and maintained Butterfly Valve - relatively flat, rotating disc mounted on a under a quality control program to ensure conformance bearing that allows it to rotate its axis. with design specifications. Bypass Valve - ON/OFF valve that allows fluid to bypass Check Valve - a valve that allows flow in one direction a station when open, and forces fluid to enter a station only. when closed; operates together with the station inlet Choke - A device with a fixed (positive) or variable valve. (adjustable) orifice installed in a line to restrict the flow and control the rate of production from the well. C. Choked Flow 1) operating condition that occurs when Can-type Vertical Pumps - pump where liquid enters pressure at the vena contracta drops below the liquid through the inlet valve and flows to the can bottom vapor pressure and the liquid starts to vaporize and form increasing the pump suction head. bubbles; 2) operating condition that occurs when the fluid Capacity - volume of fluid per unit time that the pump or velocity reaches its sonic velocity in the equipment and compressor can move. no additional flow can be handled. Capacity Control - use of varying operating speeds to Choke Manifold - Used to control flowing pressure from control the volume of fluid moved under certain given underbalance well. May be used on connections or trips to conditions. either keep production from displacing the drilling fluid (HP Carbon Doxide/Monoxide – Naturally occurring gas wells), or to artificially charge the annulus to avoid loading substances resulting from combustion of hydrocarbons. to reservoir pressure equilibrium (prolific oil wells). Are also found as components in hydrocarbon reservoirs. Christmas Tree - The collection of fittings and valves, on Cascade Shutdown - gradual shutdown of the units in a the top of the casing, controlling the hydrocarbon production station where the units are shutdown one by one in rate. specified intervals. Clearance - percentage of the swept volume of gas through Case Remote Warning