Glossary
Browse the IADC Lexicon alphabetically or by category. Get comprehensive definitions of drilling industry terms.
Stress Relief
Definition(s)
Stress Relief
Controlled heating of material to a predetermined temperature for the purpose of reducing any residual stresses after welding. Source: API SPEC 6A, Specification for Wellhead and Christmas Tree Equipment, Twentieth Edition, October 2010 (Addendum November 2012). Global Standards Source: API SPEC 16C, Specification for Choke and Kill Systems, First Edition, January 1993 (Reaffirmed 2001). Global StandardsStress Relief
Controlled heating of material to a predetermined temperature for the purpose of reducing any residual stresses. Source: API Specification 16A, Specification for Drill-through Equipment, Fourth Edition, April 2017. Global Standards Source: API STANDARD 16AR, Standard for Repair and Remanufacture of Drill-through Equipment, First Edition, April 2017. Global Standards Source: API SPEC 14A, Specification for Subsurface Safety Valve Equipment, Eleventh Edition, October 2005 (Reaffirmed June 2012). Global Standards Source: API SPEC 16A, Specification for Drill-through Equipment, Third Edition, June 2004 (Errata/Supplement November 2004). Global Standards Source: API SPEC 16RCD, Specification for Drill Through Equipment—Rotating Control Devices, Upstream Segment, First Edition, February 2005. Global StandardsStainless Steel
Definition(s)
Stainless Steel
Steel containing more than 11 % mass fraction chromium to render the steel corrosion resistant. NOTE Other elements may be added to secure special properties. Source: API SPEC 6A, Specification for Wellhead and Christmas Tree Equipment, Twentieth Edition, October 2010 (Addendum November 2012). Global StandardsStainless Steel
Steel containing chromium, more than 11%, to render the steel corrosion resistant. Other elements may be added to secure special properties. Source: API SPEC 16C, Specification for Choke and Kill Systems, First Edition, January 1993 (Reaffirmed 2001). Global StandardsSSV Valve or USV Valve
Definition(s)
SSV Valve or USV Valve
Portion of the SSV/USV that contains the wellstream and shuts off flow when closed. Source: API SPEC 6A, Specification for Wellhead and Christmas Tree Equipment, Twentieth Edition, October 2010 (Addendum November 2012). Global StandardsSSV Actuator or Underwater Safety Valve Actuator or USV Actuator
Definition(s)
SSV Actuator or Underwater Safety Valve Actuator or USV Actuator
Device which causes the SSV/USV valve to open when power is supplied and to close automatically when power is lost or released. Source: API SPEC 6A, Specification for Wellhead and Christmas Tree Equipment, Twentieth Edition, October 2010 (Addendum November 2012). Global StandardsSlip-Type Casing Hanger
Definition(s)
Slip-Type Casing Hanger
Mechanism used to support a casing string in a casing head by gripping the pipe with wedge-type members. Source: API SPEC 6A, Specification for Wellhead and Christmas Tree Equipment, Twentieth Edition, October 2010 (Addendum November 2012). Global StandardsSerialization
Definition(s)
Serialization
Assignment of a unique code to individual parts and/or pieces of equipment to maintain records. Source: API Specification 16A, Specification for Drill-through Equipment, Fourth Edition, April 2017. Global Standards Source: API STANDARD 16AR, Standard for Repair and Remanufacture of Drill-through Equipment, First Edition, April 2017. 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 Standards Source: API SPEC 16C, Specification for Choke and Kill Systems, First Edition, January 1993 (Reaffirmed 2001). Global Standards Source: API SPEC 16RCD, Specification for Drill Through Equipment—Rotating Control Devices, Upstream Segment, First Edition, February 2005. Global StandardsSecondary Equipment
Definition(s)
Secondary Equipment
Piece of equipment that can normally be isolated from the well fluid or well pressure. Source: API SPEC 6A, Specification for Wellhead and Christmas Tree Equipment, Twentieth Edition, October 2010 (Addendum November 2012). Global StandardsSandy Service
Definition(s)
Sandy Service
Intended for use in wells where particulates such as sand can be expected to cause equipment failure. Source: API SPEC 6A, Specification for Wellhead and Christmas Tree Equipment, Twentieth Edition, October 2010 (Addendum November 2012). Global StandardsRounded Indication
Definition(s)
Specification 16A
─ For liquid penetrant or magnetic particle examination: any indication that is approximately circular or elliptical and whose length is less than three times its width ─ For radiographic examination: any indication with a maximum length of three times the width or less on the radiograph.- NOTE: Indications may be circular, elliptical, conical, or irregular in shape, and may have tails. When evaluating the size of an indication, the tail is included.
Rounded Indication
Surface NDE indication that is circular or elliptical, having a length less than 3 times its width. Source: API SPEC 6A, Specification for Wellhead and Christmas Tree Equipment, Twentieth Edition, October 2010 (Addendum November 2012). Global StandardsRounded Indication
Indication, revealed by NDE, with a circular or elliptical shape and having a length less than three times its width. Source: API SPEC 7K, Drilling and Well Servicing Equipment Upstream Segment, Fifth Edition, June 2010 (August 2010). Global Standards Source:API SPECIFICATION 7K, Drilling and Well Servicing Equipment, Sixth Edition, December 2015. Global StandardsRounded Indication
An indication revealed by NDE, with a circular shape or with an elliptical shape having a length of less than three times the width. Source: API SPEC 8C, Drilling and Production Hoisting Equipment (PSL 1 and PSL 2), Fifth Edition, April 2012. Global StandardsRounded Indication
Indication which is circular or elliptical with its length less than three times the width. Source: API SPEC 16R, Specification for Marine Drilling Riser Couplings, Exploration and Production Department, First Edition, January 1997. Global StandardsRetained Fluid
Definition(s)
Retained Fluid
Actual fluid produced by a well or injected into a well. Source: API SPEC 6A, Specification for Wellhead and Christmas Tree Equipment, Twentieth Edition, October 2010 (Addendum November 2012). Global StandardsRetained Fluid
The actual fluid produced by a well. Source: API SPEC 16C, Specification for Choke and Kill Systems, First Edition, January 1993 (Reaffirmed 2001). Global StandardsRestricted-Area Sealing Means Or Restricted-Area Pack-Off
Definition(s)
Restricted-Area Sealing Means Or Restricted-Area Pack-Off
Pack-off or other device used to isolate an area at higher pressure from one at lower pressure. NOTE This device serves to limit pressure-induced loads on connectors or areas of a lower pressure rating. It may also be a seal that encloses a pressure-containment area smaller than the adjacent ring gasket or connector seal. Source: API SPEC 6A, Specification for Wellhead and Christmas Tree Equipment, Twentieth Edition, October 2010 (Addendum November 2012). Global StandardsReplacement Part
Definition(s)
Replacement Part
Part used to repair/remanufacture a piece of equipment that meets the wellhead and christmas tree requirement for the applicable repair/remanufacture level. Source: API SPEC 6A, Specification for Wellhead and Christmas Tree Equipment, Twentieth Edition, October 2010 (Addendum November 2012). Global StandardsRepairer/Remanufacturer
Definition(s)
Repairer/Remanufacturer
Principal agent in the repair and remanufacture of wellhead and christmas tree equipment who chooses to be in compliance with this International Standard. Source: API SPEC 6A, Specification for Wellhead and Christmas Tree Equipment, Twentieth Edition, October 2010 (Addendum November 2012). Global StandardsRepair Level
Definition(s)
Repair Level
Level to which equipment will be repaired or remanufactured in compliance with this International Standard. Source: API SPEC 6A, Specification for Wellhead and Christmas Tree Equipment, Twentieth Edition, October 2010 (Addendum November 2012). Global StandardsReduced-Opening Valve
Definition(s)
Reduced-Opening Valve
Valve with either a regular or Venturi-type opening, either circular or non-circular, through the closure mechanism. Source: API SPEC 6A, Specification for Wellhead and Christmas Tree Equipment, Twentieth Edition, October 2010 (Addendum November 2012). Global StandardsRecord, Noun
Definition(s)
Record, Noun
Document or dataset created and maintained that provides objective evidence of activities performed, results achieved, or statements made.
Source: API STANDARD 16AR, Standard for Repair and Remanufacture of Drill-through Equipment, First Edition, April 2017. Global StandardsRecord, Noun
Retrievable document or dataset created that provides objective evidence of activities performed, results achieved, or statements made. Source: API Specification 16A, Specification for Drill-through Equipment, Fourth Edition, April 2017. Global StandardsRecord, Noun
Retrievable information. 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 StandardsProration Bean
Definition(s)
Proration Bean
Type of positive choke bean of fixed length used to regulate the flow of fluid from a well. NOTE Proration is a system of allocating the amount of oil or gas a well or field is allowed to produce within a given period by a regulatory agency. Source: API RP 17A Addendum 1, Design and Operation of Subsea Production Systems—General Requirements and Recommendations, December 2010. Global StandardsProlongation
Definition(s)
Prolongation
Extension of a piece of raw material or an extension of a production part made integrally during forging, hot working, cold working or casting. Source: API RP 17A Addendum 1, Design and Operation of Subsea Production Systems—General Requirements and Recommendations, December 2010. Global StandardsPrimary Equipment
Definition(s)
Primary Equipment
Pieces of equipment that cannot normally be isolated from well fluid or well pressure. Source: API RP 17A Addendum 1, Design and Operation of Subsea Production Systems—General Requirements and Recommendations, December 2010. Global StandardsPressure-Controlling Part
Definition(s)
Pressure-Controlling Part
Part intended to control or regulate the movement of wellbore fluids.- NOTE: Examples include packing elements, rams, and replaceable seats within a pressure-containing part.
Pressure-Controlling Part
Parts intended to control or regulate the movement of wellbore fluids.- NOTE: 1 Examples include packing elements, rams, and replaceable seats within a pressure-containing member or part.
- NOTE: 2 In this document, the use of the word component and member are interchangeable.
Pressure-Controlling Part
Part intended to control or regulate the movement of pressurized fluids. EXAMPLES Valve-bore sealing mechanisms, choke trim and hangers. Source: API SPEC 17D, Design and Operation of Subsea Production Systems—Subsea Wellhead and Tree Equipment, Upstream Segment, Second Edition May 2011 (Errata September 2011). Global Standards Source: API RP 17A Addendum 1, Design and Operation of Subsea Production Systems—General Requirements and Recommendations, December 2010. GlobalPressure-Containing Weld
Definition(s)
Pressure-Containing Weld
Weld whose absence or failure will reduce or compromise the pressure-containing integrity of the component. Source: API Specification 16A, Specification for Drill-through Equipment, Fourth Edition, April 2017. Global Standards Source: API STANDARD 16AR, Standard for Repair and Remanufacture of Drill-through Equipment, First Edition, April 2017. Global StandardsPressure-Containing Weld
Weld whose absence reduces the pressure-containing integrity of the part. Source: API RP 17A Addendum 1, Design and Operation of Subsea Production Systems—General Requirements and Recommendations, December 2010. Global StandardsPressure-Containing Weld
Weld whose failure will reduce the pressure-containing integrity of the component. Source: API SPEC 16A, Specification for Drill-through Equipment, Third Edition, June 2004 (Errata/Supplement November 2004). Global StandardsPressure-Containing Part
Definition(s)
Pressure-Containing Part
Part exposed to wellbore fluids whose failure to function as intended would result in a release of wellbore fluid to the environment.- NOTE: 1 Examples include bodies and bonnets.
- NOTE: 2 Examples of items that are not included are operating cylinders and cylinder heads.
Pressure-Containing Part
Part whose failure to function as intended results in a release of retained fluid to the atmosphere. EXAMPLES Bodies, bonnets, one-piece stems, and that segment of multi piece stems that passes through the pressure boundary, are pressure-containing parts. Source: API RP 17A Addendum 1, Design and Operation of Subsea Production Systems—General Requirements and Recommendations, December 2010. Global StandardsPressure-Containing Part
Part whose failure to function as intended results in a release of wellbore fluid to the environment. EXAMPLES Bodies, bonnets, stems. Source: API SPEC 17D, Design and Operation of Subsea Production Systems—Subsea Wellhead and Tree Equipment, Upstream Segment, Second Edition May 2011 (Errata September 2011). Global StandardsPressure-Boundary Penetration
Definition(s)
Pressure-Boundary Penetration
Device that penetrates directly into or communicates with the well-bore and is not defined elsewhere in this International Standard. EXAMPLES Grease or sealant injection fitting; check valve; control, test or gauge port plug and fitting, needle valve on test, gauge or injection port; electric and control line penetration. Source: API RP 17A Addendum 1, Design and Operation of Subsea Production Systems—General Requirements and Recommendations, December 2010. Global StandardsPressure Integrity
Definition(s)
Pressure Integrity
Structural and leak-resistant capability of a product to contain applied pressure. Source: API RP 17A Addendum 1, Design and Operation of Subsea Production Systems—General Requirements and Recommendations, December 2010. Global StandardsPressure Integrity
The structural and leak resistant capability of a product to contain applied pressure. Source: API SPEC 16C, Specification for Choke and Kill Systems, First Edition, January 1993 (Reaffirmed 2001). Global StandardsPost-Weld Heat Treatment
Definition(s)
Post-Weld Heat Treatment
Heat treatment subsequent to welding, including stress relief.
Source: API Specification 16A, Specification for Drill-through Equipment, Fourth Edition, April 2017. Global StandardsPost-Weld Heat Treatment
Any heat treatment subsequent to welding, including stress relief. Source: API RP 17A Addendum 1, Design and Operation of Subsea Production Systems—General Requirements and Recommendations, December 2010. Global Standards Source: API SPEC 16C, Specification for Choke and Kill Systems, First Edition, January 1993 (Reaffirmed 2001). Global Standards Source: API SPEC 16RCD, Specification for Drill Through Equipment—Rotating Control Devices, Upstream Segment, First Edition, February 2005. Global StandardsPlug Valve
Definition(s)
Plug Valve
Valve assembly with a plug permanently mounted across the conduit so that, when rotated 90°, it effects a closure. EXAMPLES Plugs may be straight, tapered, ball, etc. Source: API RP 17A Addendum 1, Design and Operation of Subsea Production Systems—General Requirements and Recommendations, December 2010. Global StandardsPlug Valve
Wedge shaped, reduced part valve with 90- degree rotation; causes high-pressure drop. Source: IADC UBO / MPD Glossary, December 2011. Global StandardsPart
Definition(s)
Part
Individual piece used in the assembly of single equipment units.- EXAMPLES Body, bonnet, gate, stud, handwheel, etc., are parts of a valve. A part may also be a piece not in finished form.
Part
Individual piece used in the assembly of a single unit of equipment. Source: API Specification 16A, Specification for Drill-through Equipment, Fourth Edition, April 2017. Global Standards Source: API STANDARD 16AR, Standard for Repair and Remanufacture of Drill-through Equipment, First Edition, April 2017. Global Standards Source: API SPEC 16A, Specification for Drill-through Equipment, Third Edition, June 2004 (Errata/Supplement November 2004). Global StandardsPart
An individual piece used in the assembly of a single equipment unit. Source: API SPEC 16RCD, Specification for Drill Through Equipment—Rotating Control Devices, Upstream Segment, First Edition, February 2005. Global StandardsOriginal Product Definition
Definition(s)
Original Product Definition
Complete design verified and validated definition of the requirements for the original assembled product, single equipment unit, or component part, including specified limits, tolerances, health requirements, safety requirements, environmental requirements, limitations of use, customer-specific requirements, design acceptance criteria, materials of construction, materials processing requirements, physical properties, physical dimensions, requirements for manufacturing process controls, inspection, assembly, testing, marking, handling, storage, maintenance, service, and records requirements.
Source: API STANDARD 16AR, Standard for Repair and Remanufacture of Drill-through Equipment, First Edition, April 2017. Global Standards