Glossary
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Intermediate Casing
Definition(s)
Intermediate Casing
One or more strings of casing run between the surface casing and the production casing or the production liner and is cemented in place. intermediate casing is generally run in deeper wells to isolate abnormal pressured formations, lost circulation zones, salt sections, and unstable shale sections so deeper drilling can proceed with normal mud weights. A large number of wells are drilled without running intermediate casing. Source: API BULLETIN E3, Environmental Guidance Document: Well Abandonment and Inactive Well Practices for U.S. Exploration and Production Operations, First Edition, January 1993 (Reaffirmed June 2000). Global StandardsIntermediate Casing
Casing that is set when geological characteristics or wellbore conditions require isolation. These conditions include, but are not limited to, prevention of lost circulation, formation fluid influx or hole instability. Multiple intermediate casing strings can be run in a single well. Source: API STD 65 – Part 2, Isolating Potential Flow Zones During Well Construction, Upstream Segment, Second Edition, December 2010. Global StandardsIntermediate Casing
Long casing string (12 1/4 in. drift, sizes range 13 3/8 in. to 14 in.) with casing hanger in the subsea wellhead housing. Normal clearance casing OD in.: 13 3/8. Tight clearance casing OD in.: 13 5/8. NOTE These are examples only. Each well can have variations in number of casing strings and sizes. Naming conventions can vary. The heavy-wall surface casing designs may allow 13 5/8 in. to be run as a liner and not tied back. Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global StandardsIntermediate Casing
"Intermediate casing" means a casing string run between the surface casing and the production casing or production liner and cemented in place to isolate abnormally geo-pressured strata, lost circulation zones, salt sections, or unstable shale sections. Source: Alaska Oil and Gas Conservation Commission, Definitions, Alaska Admin. Code tit. 20, § 25.990, December 7, 2012. RegulationsIntermediate Casing
"Intermediate casing" means the casing string or strings run after setting the surface casing and prior to setting the production string or liner. Source: Corporation Commission, Oil and Gas Conservation, Oklahoma Administrative Code 165:10, February 2013. RegulationsIntermediate Casing
“Intermediate casing” means one or more strings of casing set after surface casing has been cemented through the base of the deepest underground source of drinking water, but before drilling into the permitted hydrocarbon reservoir(s) to isolate hydrocarbon or brine bearing flow zones, stabilize the wellbore, to isolate protected groundwater if encountered after drilling below surface casing, isolate lost circulation zones or other potential geologic hazards, or serve as a base for well control equipment. Source: Division of Mineral Resources Management - Oil and Gas, Ohio Administrative Code, Chapter 1501:9, January 2012. RegulationsIntermediate Casing
Intermediate casing—A string of casing set after the surface casing and before production casing, not to include coal protection casing, that is used in the wellbore to isolate, stabilize or provide well control. Source: Oil and Gas Wells, Pennsylvania Code, Title 25, Chapter 78, December 2012. RegulationsInactive Well
Definition(s)
Inactive Well
A well where production, injection, disposal or workover operations have ceased, but permanent abandonment has not taken place. inactive wells should be classified as either shut-in or temporarily abandoned. Shut-in status should begin 90 days after operations stop, and temporarily abandoned status should commence one day after temporary abandonment operations have been completed. Source: API BULLETIN E3, Environmental Guidance Document: Well Abandonment and Inactive Well Practices for U.S. Exploration and Production Operations, First Edition, January 1993 (Reaffirmed June 2000). Global StandardsInactive Well
INACTIVE WELL shall mean any shut-in well from which no production has been sold for a period of twelve (12) consecutive months; any well which has been temporarily abandoned for a period of six (6) consecutive months; or, any injection well which has not been utilized for a period of twelve (12) consecutive months. Source: Oil and Gas Conservation Commission, Practice and Procedure, Code of Colorado Regulations, 2 CCR 404-1, February 2013. RegulationsInactive Well
An unplugged well that has been spudded or has been equipped with cemented casing and that has had no reported production, disposal, injection, or other permitted activity for a period of greater than 12 months. Source: Oil and Gas Division, Texas Administrative Code, Title 16, Chapter 3, February 2013. RegulationsFluid Spacer
Definition(s)
Fluid Spacer
An oil or water based fluid used to separate incompatible drilling fluid from cement. Spacers are compatible with both the drilling fluid and the cement. The purpose of spacers is to minimize cement contamination by drillllig fluid and to displace drilling fluid from the wellbore 60 that the cement can form an effective hydraulic seal. Source: API BULLETIN E3, Environmental Guidance Document: Well Abandonment and Inactive Well Practices for U.S. Exploration and Production Operations, First Edition, January 1993 (Reaffirmed June 2000). Global StandardsFloat Shoe
Definition(s)
Float Shoe
A guide shoe run on the bottom of the casing string that incorporates a ball or spring-loaded backpressure valve which prevents wellbore fluid from entering the casing while the pipe is lowered in the well. Performs the same function as the float collar. Source: API BULLETIN E3, Environmental Guidance Document: Well Abandonment and Inactive Well Practices for U.S. Exploration and Production Operations, First Edition, January 1993 (Reaffirmed June 2000). Global StandardsFloat Collar
Definition(s)
Float Collar
A short cylindrical section of steel which is placed in the casing string above the guide shoe. The float collar usually incorporates a bail or spring-loaded backpressure valve which prevents wellbore fluid from entering the casing while the pipe is lowered in the well. This makes the casing buoyant, thereby reducing the derrick stress while running casing. Source: API BULLETIN E3, Environmental Guidance Document: Well Abandonment and Inactive Well Practices for U.S. Exploration and Production Operations, First Edition, January 1993 (Reaffirmed June 2000). Global StandardsDump Bailer
Definition(s)
Dump Bailer
A cylindrical container with a shear device that is used to release small batches of cement downhole on impact or by electrical activation. Used primarily to install cement on downhole tools such as bridge plugs or cement retainers. Source: API BULLETIN E3, Environmental Guidance Document: Well Abandonment and Inactive Well Practices for U.S. Exploration and Production Operations, First Edition, January 1993 (Reaffirmed June 2000). Global StandardsDisplacement Fluid
Definition(s)
Displacement Fluid
In oil well cementing, the fluid, usually drilling mud or salt water, that is pumped into the well after the cement is pumped to displace the cement from the casing and into the annulus and to prevent the cement from re-entering the casing after pumping stops. Source: API BULLETIN E3, Environmental Guidance Document: Well Abandonment and Inactive Well Practices for U.S. Exploration and Production Operations, First Edition, January 1993 (Reaffirmed June 2000). Global StandardsCorrosive Oilfield Water
Definition(s)
Corrosive Oilfield Water
A water that induces corrosion of the casing, tubing, and wellhead because of low pH and elevated levels of temperature, pressure, bacteria, dissolved gases, and dissolved solids. The severity of the corrosion increases with an increase in the velocity of oilfield waters across the surfaces of the casing, tubing, and wellhead. Water found in fresh water aquifers typically is near ambient temperature, has low levels of dissolved gases and solids and has a relatively low velocity. As a result, fresh water aquifers are generally not very corrosive. Source: API BULLETIN E3, Environmental Guidance Document: Well Abandonment and Inactive Well Practices for U.S. Exploration and Production Operations, First Edition, January 1993 (Reaffirmed June 2000). Global StandardsConcentric Tubing
Definition(s)
Concentric Tubing
Small diameter tubing installed inside conventional tubing or tubingless completions, normally with the christmas tree in place, using a small rig or hoisting unit. Source: API BULLETIN E3, Environmental Guidance Document: Well Abandonment and Inactive Well Practices for U.S. Exploration and Production Operations, First Edition, January 1993 (Reaffirmed June 2000). Global StandardsCompletion Interval
Definition(s)
Completion Interval
The geologic formations in a well where production, injection or disposal operations are taking place. Source: API BULLETIN E3, Environmental Guidance Document: Well Abandonment and Inactive Well Practices for U.S. Exploration and Production Operations, First Edition, January 1993 (Reaffirmed June 2000). Global StandardsCompletion Interval
“Completion interval” means a section within a well that is prepared to permit the- production of fluids from the well;
- observation of the performance of a reservoir; or
- injection of fluids into the well (intervalle de complétion).
Coiled Tubing
Definition(s)
Coiled Tubing
A continuous length of small diameter (i.e., usually 1" to 1-3/4”) ductile steel tubing which is coiled onto a reel. The tubing is fed into the well by an injector head through a coiled tubing blow-out preventer or stufñng box. The coiled tubing may be used for pumping fluids, including cement, into the wellbore. Source: API BULLETIN E3, Environmental Guidance Document: Well Abandonment and Inactive Well Practices for U.S. Exploration and Production Operations, First Edition, January 1993 (Reaffirmed June 2000). Global StandardsCoiled Tubing
Intervention using continuous tubing. Source: NORSOK D-002, Well intervention equipment, Rev. 2, June 2013. Global StandardsCement Retainer
Definition(s)
Cement Retainer
A tool (composed primarily of slips, a ported mandrel, and rubber sealing elements) set in the casing which allows cement or other fluids to be pumped through the tool, but seals against any fluid movement when the tubing is released from the tool. The cement retainer is generally used in squeeze cementing work. The cement retainer cannot be unset once it has been set in the casing but it can be drilled out. Source: API BULLETIN E3, Environmental Guidance Document: Well Abandonment and Inactive Well Practices for U.S. Exploration and Production Operations, First Edition, January 1993 (Reaffirmed June 2000). Global StandardsCement Plug
Definition(s)
Cement Plug
A volume of cement placed at some interval inside the wellbore to prevent fluid movement. Source: API BULLETIN E3, Environmental Guidance Document: Well Abandonment and Inactive Well Practices for U.S. Exploration and Production Operations, First Edition, January 1993 (Reaffirmed June 2000). Global StandardsCement
Definition(s)
Cement
A powder consisting of alumina, silica, lime, and other substances that hardens when mixed with water. Cements are used in oil, gas, geothermal, injection, or water wells for protecting and supporting casing, isolating intervals within the wellbore, repairing casing leaks, sealing perforated or open hole intervals, and protecting fresh water aquifers. Well cements are manufactured to meet MI Specification lOA, which includes chemical, physical, and performance requirements for MI Classes A through H. Source: API BULLETIN E3, Environmental Guidance Document: Well Abandonment and Inactive Well Practices for U.S. Exploration and Production Operations, First Edition, January 1993 (Reaffirmed June 2000). Global StandardsCement (or Portland Cement)
Ground clinker generally consisting of hydraulic calcium silicates and aluminates and usually containing one or more of the forms of calcium sulfate as an interground addition. NOTE 1 Hydraulic calcium silicates and aluminates are those which harden under water. NOTE 2 Interground additions are added before grinding, rather than after grinding. Source: API RP 10B-2, Recommended Practice for Testing Well Cements, First Edition, July 2005 (Reaffirmed: July 2010). Global StandardsCement
“Cement” means a complex, finely-ground kiln-fired calcium silicate which, when mixed with water, forms a slurry which will harden in the borehole to form an effective seal between the well bore and casing or tubing, or to effectively seal formations penetrated by the well bore. Source: Division of Mineral Resources Management - Oil and Gas, Ohio Administrative Code, Chapter 1501:9, January 2012. RegulationsCement
Cement—A mixture of materials for bonding or sealing that attains a 7-day maximum permeability of 0.01 millidarcies and a 24-hour compressive strength of at least 500 psi in accordance with applicable standards and specifications. Source: Oil and Gas Wells, Pennsylvania Code, Title 25, Chapter 78, December 2012. RegulationsCasing Shoe
Definition(s)
Casing Shoe
A short, heavy cylindrical section of steel, filled with cement, which is placed at the end (bottom) of the casing string. It prevents the casing from snagging on irregularities in the borehole as it is lowered. A passage through the center of the shoe allows drilling fluid to pass up into the casing while it is being lowered and allows cement to pass through and circulate behind the casing during cementing operations. Also called the guide shoe. When running casing in deeper wells, a float collar is run in addition to a guide shoe. Source: API BULLETIN E3, Environmental Guidance Document: Well Abandonment and Inactive Well Practices for U.S. Exploration and Production Operations, First Edition, January 1993 (Reaffirmed June 2000). Global StandardsCasing Shoe
A tool joint connected to the bottom of a string of casing designed to guide the casing past irregularities in the open hole; usually rounded at the bottom in shape and composed of drillable materials. Source: API RP 59, Recommended Practice for Well Control Operations, Second Edition, May 2006. Global Standards Source: API RP 64, Recommended Practice for Diverter Systems Equipment and Operations, Second Edition, November 2001 (March 1, 2007). Global StandardsCasing Packer
Definition(s)
Casing Packer
A downhole tool (composed primarily of slips, an open mandrel, and a rubber sealing element) that is installed in wells to seal the tubing-casing annulus and protect the casing from fluids produced through or pumped down the tubing and to isolate the casing from pressure(s). Source: API BULLETIN E3, Environmental Guidance Document: Well Abandonment and Inactive Well Practices for U.S. Exploration and Production Operations, First Edition, January 1993 (Reaffirmed June 2000). Global StandardsCasing Head
Definition(s)
Casing Head (or Braden Head)
A heavy steel fitting connected to the uppermost end of the surface casing. It provides a pressure seal for subsequent casing strings placed in the well and allows suspension of intermediate casing strings and the production casing. It also provides outlets to release any pressure that might accumulate between casing strings. The casing head is usually connected to the surface casing by a threaded connection, but in deep wells it may be attached by welding. Source: API BULLETIN E3, Environmental Guidance Document: Well Abandonment and Inactive Well Practices for U.S. Exploration and Production Operations, First Edition, January 1993 (Reaffirmed June 2000). Global StandardsBullhead Squeeze
Definition(s)
Bullhead Squeeze
The process by which hydraulic pressure is applied to a workstring or tubing to force fluids, such as cement, outside the wellbore. Annular flow (returns) is prevented by a packer set in the casing above the perforated and/or open hole interval. The packer shields the inner casing wall from exposure to the pumping pressures. Source: API BULLETIN E3, Environmental Guidance Document: Well Abandonment and Inactive Well Practices for U.S. Exploration and Production Operations, First Edition, January 1993 (Reaffirmed June 2000). Global StandardsBridge Plug
Definition(s)
Bridge Plug
A downhole tool (composed primarily of slips, a plug mandrel, and a rubber sealing element) that is run and set in casing to isolate a lower zone while an upper section is tested, cemented, stimulated, produced, or injected into. In order to facilitate removal by drilling, a bridge plug is often made of cast iron and is commonly referred to as a cast iron bridge plug (CIBP). Source: API BULLETIN E3, Environmental Guidance Document: Well Abandonment and Inactive Well Practices for U.S. Exploration and Production Operations, First Edition, January 1993 (Reaffirmed June 2000). Global StandardsBridge Plug
Mechanical device installed in, and used for blocking fluid (liquid or gas) communication in, the conduit and not installed in a designed receptacle. Source: API SPEC 11D1, Packers and Bridge Plugs, Upstream Segment, Second Edition, July 2009. Global StandardsBradenhead Squeeze
Definition(s)
Bradenhead Squeeze
The process by which hydraulic pressure is applied to a casing, workstring, or tubing, to force fluids, such as cement, outside the wellbore. Annular returns may be prevented by closing the casinghead valves. A packer is not run in the well. Therefore, the inner casing wall is exposed to the pumping pressures. Source: API BULLETIN E3, Environmental Guidance Document: Well Abandonment and Inactive Well Practices for U.S. Exploration and Production Operations, First Edition, January 1993 (Reaffirmed June 2000). Global StandardsBorehole
Definition(s)
Borehole
The hole made by drilling a well. Where casing is run in the well, the borehole is the space between the exterior of the casing and the formations. After the casing has been installed, the borehole is normally filled with various materials such as cement, drilling mud, sloughing formations, and water. Source: API BULLETIN E3, Environmental Guidance Document: Well Abandonment and Inactive Well Practices for U.S. Exploration and Production Operations, First Edition, January 1993 (Reaffirmed June 2000). Global StandardsBalanced Cement Plug
Definition(s)
Balanced Cement Plug
The result of pumping cement through drill pipe, workstring, or tubing until the level of cement outside is equal to that inside the drill pipe/ workstring/ tubing. The pipe is then pulled slowly from the Cement slurry, leaving the plug in place. The technique is used in both open hole and cased hole applications when the wellbore fluids are in static equilibrium. Source: API BULLETIN E3, Environmental Guidance Document: Well Abandonment and Inactive Well Practices for U.S. Exploration and Production Operations, First Edition, January 1993 (Reaffirmed June 2000). Global StandardsControl Station/Panel, Remote
Definition(s)
Control Station/Panel, Remote
A panel containing a series of controls that will operate the BOP functions from a location that is remote from the hydraulic control manifold, or central processor in the case of a MUX or Multiplex control system. NOTE: The control station for a discrete hydraulic system is at the HPU. Source: API STD 53, Blowout Prevention Equipment Systems for Drilling Wells, Upstream Segment, Fourth Edition, November 2012. Global StandardsControl Panel, Remote
A panel containing a series of controls that will operate the valves on the control manifold from a remote point. Source: API RP 59, Recommended Practice for Well Control Operations, Second Edition, May 2006. Global StandardsWPS
Definition(s)
WPS
Welding procedure specification. Source: API 570, Piping Inspection Code: In-service Inspection, Rating, Repair, and Alteration of Piping Systems, Fourth Edition, February 2016, with Addendum May 2017. Global Standards Source: API Specification 16A, Specification for Drill-through Equipment, Fourth Edition, April 2017. Global Standards Source:API SPECIFICATION 19TT, Specification for Downhole Well Test Tools and Related Equipment, First Edition, October 2016. Global Standards Source: API SPEC 5DP, Specification for Drill Pipe, First Edition, August 2009. Global Standards Source: API SPEC 6A, Specification for Wellhead and Christmas Tree Equipment, Twentieth Edition, October 2010 (Addendum November 2012). Global Standards Source: API SPEC 16A, Specification for Drill-through Equipment, Third Edition, June 2004 (Errata/Supplement November 2004). Global StandardsWPS
Weld procedure specification. Source: API STANDARD 16AR, Standard for Repair and Remanufacture of Drill-through Equipment, First Edition, April 2017. Global Standards Source: API STD 53, Blowout Prevention Equipment Systems for Drilling Wells, Upstream Segment, Fourth Edition, November 2012. Global StandardsWPS
Written welding procedure that is qualified to provide direction for welding in accordance with requirements of this standard and describing the specific essential, nonessential, and supplementary essential variables required for each welding process.- NOTE: These variables and their meanings are defined in ASME BPVC Section IX, Article II and Article IV.
WPS
Document providing the required welding variables for a specific application to assure repeatability by properly trained welders and welding operators.- NOTE: These variables and their meanings are defined, respectively, in Article II of the ASME Boiler & Pressure Vessel Code, Section IX—Welding and Brazing Qualifications.
WPS
Welding Procedure Specifications. Source: API SPEC 16C, Specification for Choke and Kill Systems, First Edition, January 1993 (Reaffirmed 2001). Global Standards Source: API SPEC 16D, Specification for Control Systems for Drilling Well Control Equipment and Control Systems for Diverter Equipment, Upstream Segment, Second Edition, July 2004. Global Standards Source: API SPEC 16RCD, Specification for Drill Through Equipment—Rotating Control Devices, Upstream Segment, First Edition, February 2005. Global Standards Source: Verification of Lifting Appliances for the Oil and Gas Industry, DNV-OSS-308, October 2010, Det Norske Veritas AS, Global StandardsWell Control Equipment
Definition(s)
Well Control Equipment
Systems and subsystems (components, parts, or assemblies) that are used to control pressure within the wellbore. Source: API STD 53, Blowout Prevention Equipment Systems for Drilling Wells, Upstream Segment, Fourth Edition, November 2012. Global StandardsWell Control Equipment
Well control equipment includes all equipment used to:- detect unplanned influxes of formation fluids into the well;
- prevent, control or divert the flow of fluids from the well;
- purge formation fluids from the well;
- separate formation fluids from the drilling fluid.