Glossary
Browse the IADC Lexicon alphabetically or by category. Get comprehensive definitions of drilling industry terms.
SSTT
Definition(s)
SSTT
Subsea test tree. Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global StandardsSRB
Definition(s)
SRB
Sulfate reducing bacteria. Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global StandardsSRB
Sulphate reducing bacteria. Source: Offshore Standard DNV-OS-C101, Design of Offshore Steel Structures, General (LRFD Method, Det Norske Veritas, April 2011. Global StandardsQC
Definition(s)
QC
Quality Control. Source: API 510, Pressure Vessel Inspection Code: In-service Inspection, Rating, Repair, and Alteration, Tenth Edition, May 2014, with Addendum May 2017. Global Standards Source: API Technical Report 17TR7, Verification and Validation of Subsea Connectors, First Edition, April 2017. Global Standards Source: ISO 16530-1:2017, Petroleum and natural gas industries — Well integrity – Part 1: Life cycle governance, First Edition, March 2017. Global Standards Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global Standards Source: API SPEC 11D1, Packers and Bridge Plugs, Upstream Segment, Second Edition, July 2009. Global Standards Source: ISO 19900:2013, Petroleum and natural gas industries – General requirements for offshore structures. Global StandardsQC
Those physical activities that are conducted to check conformance with specifications in accordance with the QA plan.
Source: API 510, Pressure Vessel Inspection Code: In-service Inspection, Rating, Repair, and Alteration, Tenth Edition, May 2014, with Addendum May 2017. Global Standardsqc
Cone resistance.
Source: ABS Guidance Notes on Geotechnical Performance of Spudcan Foundations, January 2017. Global StandardsQA
Definition(s)
QA
Quality Assurance. Source: API 510, Pressure Vessel Inspection Code: In-service Inspection, Rating, Repair, and Alteration, Tenth Edition, May 2014, with Addendum May 2017. Global Standards Source: ISO 16530-1:2017, Petroleum and natural gas industries — Well integrity – Part 1: Life cycle governance, First Edition, March 2017. Global Standards Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global Standards Source: NOPSEMA Guidance Note: Safety Management Systems, N04300-GN1052, Australia, Revision 0, December 2012. Regulatory Guidance Source: ISO 20815:2008, Petroleum, petrochemical and natural gas industries – Production assurance and reliability management. Global Standards Source: International Association of Drilling Contractors, Appendix 2 to Health, Safety and Environment Case Guidelines for Offshore Drilling Contractors, Issue 3.3.2, February 2010. IADC Guidelines Source: ISO 19900:2013, Petroleum and natural gas industries – General requirements for offshore structures. Global StandardsQA
All planned, systematic, and preventative actions specified to determine if materials, equipment, or services will meet specified requirements so that equipment will perform satisfactorily in service. The minimum contents of a QA inspection manual for in-service inspection are outlined in 4.1.2.
Source: API 510, Pressure Vessel Inspection Code: In-service Inspection, Rating, Repair, and Alteration, Tenth Edition, May 2014, with Addendum May 2017. Global StandardsMYS
Definition(s)
MYS
Minimum yield stress. Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global StandardsLTP
Definition(s)
LTP
Liner top packer. Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global StandardsLPWH
Definition(s)
LPWH
Low pressure wellhead housing. Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global StandardsITC
Definition(s)
ITC
Internal tree cap. Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global StandardsHTH
Definition(s)
HTH
Horizontal tubing hanger. Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global StandardsHPWHH
Definition(s)
HPWHH
High pressure wellhead housing. Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global StandardsFOSV (Full-opening safety valve)
Definition(s)
FOSV
Full-opening safety valve. Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global Standards Source: Deepwater Well Control Guidelines. IADC GuidelinesDW
Definition(s)
DW
Deepwater. Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global StandardsC&K
Definition(s)
C&K
Choke and kill. Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global Standards Source: Deepwater Well Control Guidelines. IADC GuidelinesWell Test
Definition(s)
Well Test
Flowing reservoir fluids to the surface to evaluate the reservoir and the completion. Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global StandardsWell Testing
Well testing as mentioned in the third subsection, means flow during formation testing, test production, cleanup and stimulation of the well. Source: Guidelines Regarding the Facilities Regulations, Norway, updated December 2012. Regulatory GuidanceWatch circle
Definition(s)
Watch circle
Area of predetermined size in which the drilling rig maintains its intended position (station) in order to not exceed equipment or reaction time limitations. NOTE If the rig moves to the edge of the watch circle, then attention is heightened. Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global StandardsWatch circle
The rig offset perimeter around the well location for which special procedures are to be initiated to prepare to disconnect the drilling riser or actually implement the disconnect to prevent damage due to excessive offset. 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 StandardsVerification
Definition(s)
Verification
Confirmation that specified design requirements have been fulfilled, through the provision of objective evidence.- NOTE: Typically verification is achieved by calculations, design reviews, hydrostatic testing, and factory acceptance testing (FAT).
Verification
Examination, testing, audit or review to confirm that an activity, product or service is in accordance with specified requirements. Source: ISO 16530-1:2017, Petroleum and natural gas industries — Well integrity – Part 1: Life cycle governance, First Edition, March 2017. Global StandardsVerify/verification
A quality control process used to evaluate whether or not a product, service, or system complies with a given criteria set (i.e. regulations, specifications, or conditions). NOTE Verification can be in development or production phases (often an internal process). Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global StandardsVerification
Examination to confirm that an activity, a product or a service is in accordance with specified requirements. Source: API RP 17G, Recommended Practice for Completion/Workover Risers, Second Edition, July 2006 (Reaffirmed April 2011). Global StandardsVerification
A word used in UK offshore OHS legislation, but not Australian, to describe a process related to validation but significantly broader. Source: NOPSEMA Guideline – Glossary – Regulatory Operations, N-09000-GL0326, Australia, Revision 5, December 2011. Regulatory GuidanceVerification
Confirmation, through the provision of objective evidence, that specified requirements have been fulfilled. [SOURCE: ISO 9000:2005]- Note 1 to entry: This could also be called compliance testing.
Verification
Examination made to confirm that an activity, product, or service is in accordance with specified requirements. Source: ISO 19901-7:2013, Petroleum and natural gas industries – Specific requirements for offshore structures – Part 7: Stationkeeping systems for floating offshore structures and mobile offshore units. Global Standards Source: Offshore Standard DNV-OS-C101, Design of Offshore Steel Structures, General (LRFD Method, Det Norske Veritas, April 2011. Global StandardsVerification
A service that signifies a confirmation through the provision of objective evidence (analysis, observation, measurement, test, records or other evidence) that specified requirements have been met. Source: Rules for Classification – Offshore units, DNVGL-OU-0101, Offshore drilling and support units, DNV GL, July 2015. Global StandardsVerification
An examination to confirm that an activity, a product or a service is in accordance with specified requirements. Guidance note: The examination shall be based on information, which can be proved true, based on facts obtained through observation, measurement, test or other means. ISO 8402: 1994: Verification: Confirmation by examination and provision of objective evidence that specified requirements has been fulfilled. Source: Verification of Lifting Appliances for the Oil and Gas Industry, DNV-OSS-308, October 2010, Det Norske Veritas AS, Global StandardsVerify
Definition(s)
Verify/verification
A quality control process used to evaluate whether or not a product, service, or system complies with a given criteria set (i.e. regulations, specifications, or conditions). NOTE Verification can be in development or production phases (often an internal process). Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global StandardsVerified Barrier
Definition(s)
Verified barrier
Barrier whose proper deployment has been substantiated through a postinstallation assessment or through observations recorded during its installation. NOTE A tested barrier has the greatest level of assurance. EXAMPLE Observations that can be recorded during a cement displacement operation to support the evaluation of the cement as a barrier include a mud displacement volume equal to the calculated capacity of the casing string, and observed lift pressure matching the calculated lift pressure. Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global StandardsVariable Bore Ram
Definition(s)
Variable bore ram
Closing and sealing component in a ram blowout preventer that is capable of sealing on a range of tubular sizes. Source: API Specification 16A, Specification for Drill-through Equipment, Fourth Edition, April 2017. Global StandardsVariable bore ram
A pipe ram that seals on more than one pipe size. Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global StandardsValidation
Definition(s)
Validation
Confirmation that the operational requirements for a specific use or application have been fulfilled through the provision of objective evidence. NOTE Typically validation is achieved by qualification testing and/or system integration testing. Source: API Recommended Practice 17H, Remotely Operated Tools and Interfaces on Subsea Production Systems, Second Edition, June 2013 (Addendum 1, October 2014). Global StandardsValidation
A quality assurance process of establishing evidence that provides a high degree of assurance that a product, service, or system will accomplish its intended purpose. NOTE This often involves acceptance of fit-for-purpose with end users and other product stakeholders. NOTE 2 In this document, the related term “validation” is used only with respect to the initial design of equipment (i.e. capacity calculations and any performance confirmation tests in a lab rather than in the well). Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global StandardsValidation
confirmation through the use of objective evidence that the requirements for a specific intended use or application have been fulfilled Source: ISO/IEC TS 17027:2014, Conformity assessment – Vocabulary related to competence of persons used for certification of persons, Global StandardsValidation
Confirmation, through the provision of objective evidence, that the requirements for a specific intended use or application have been fulfilled [SOURCE: ISO 9000:2005]. Source: ISO/IEC 27000:2014, Information technology — Security techniques — Information security management systems — Overview and vocabulary, Third Edition, January 2014. Global StandardsValidation
A validation of a proposed facility is a statement in writing by an independent validator in respect of the design, construction and installation (including instrumentation, process layout and process control systems) of the facility, to the extent that these matters are covered by the scope of the validation agreed between NOPSEMA and the operator. A validation of a proposed significant change to an existing facility is a statement in writing by an independent validator in respect of the proposed change, to the extent required by the scope of the validation agreed between NOPSEMA and the operator. Source: Offshore Petroleum and Greenhouse Gas Storage (Safety) Regulations 2009 (Select Legislative Instrument 2009 No. 382 as amended), Australia, prepared on 1 January 2012. RegulationsTrip Margin
Definition(s)
Trip Margin
Additional drilling or completion fluid density that provides an increment of overbalance pressure in order to compensate for effects of swabbing. Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global StandardsTrip Margin
An incremental increase in drilling fluid density to provide an increment of overbalance in order to compensate for effects of swabbing. Source: API RP 59, Recommended Practice for Well Control Operations, Second Edition, May 2006. Global StandardsTrip Margin
An incremental increase in drilling fluid density to provide an element of overbalance and compensate for the effects of swabbing Source: IADC UBO / MPD Glossary, December 2011. Global StandardsWell Total System Reliability
Definition(s)
Total system reliability or system reliability or well total system reliability
The probability over time that the combination of all physical and operational barriers will prevent unintended flow of fluid or gas. Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global StandardsSystem Reliability
Definition(s)
Total system reliability or system reliability or well total system reliability
The probability over time that the combination of all physical and operational barriers will prevent unintended flow of fluid or gas. Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global StandardsTotal System Reliability
Definition(s)
Total system reliability or system reliability or well total system reliability
The probability over time that the combination of all physical and operational barriers will prevent unintended flow of fluid or gas. Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global StandardsTested Barrier
Definition(s)
Tested barrier
A barrier whose performance has been verified through meeting the acceptance criteria of a pressure test in the direction of flow and to a pressure differential equal to or greater than the maximum differential pressure anticipated during the life of the barrier. Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global StandardsTest Ram
Definition(s)
Test ram
A ram installed in the lowest cavity of a BOP stack that is designed to hold pressure from above and seals around the drill string (used to facilitate BOP testing operations). Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global StandardsSwab
Definition(s)
Swab
The lowering of the hydrostatic pressure in the well bore due to upward movement of tubulars and/or tools. Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global StandardsSurge
Definition(s)
Surge
An increase in downhole pressure that occurs when a string is lowered in the well or when circulation is initiated. Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global StandardsSurge
Vessel motion along the for/aft axis. Source: API RP 16Q, Recommended Practice for Design, Selection, Operation and Maintenance of Marine Drilling Riser Systems, First Edition, November 1993 (Reaffirmed August 2001). Global StandardsSurge
Vessel motion along the fore/aft axis. Source: API RP 17G, Recommended Practice for Completion/Workover Risers, Second Edition, July 2006 (Reaffirmed April 2011). Global Standards Source: ISO 13624-1:2009, Petroleum and natural gas industries – Drilling and production equipment – Part 1:Design and operation of marine drilling riser equipment. Global StandardsSurge
- pressure change produced by conditions such as pump or compressor startup or shutdown, valve openings or closures, and line leaks.
- pulsating flow in centrifugal compressors caused by operating under low flow conditions.