Glossary
Browse the IADC Lexicon alphabetically or by category. Get comprehensive definitions of drilling industry terms.
Ambient Pressure
Definition(s)
Ambient Pressure
Pressure external to the wellhead- Note 1 to entry: In the case of a surface wellhead, the pressure is 0 kPa (0 psig). In the case of a subsea wellhead, it is equal to the hydrostatic pressure of seawater at the depth of the subsea wellhead.
Ambient Pressure
Pressure external to the wellhead. In the case of a surface wellhead, it would be zero psig. In the case of a subsea wellhead, it would be equal to the hydrostatic pressure of seawater at the depth of the subsea wellhead in psig. Source: API RP 90, Annular Casing Pressure Management for Offshore Wells, Upstream Segment. First Edition, August 2006. Global StandardsAmbient Pressure
Pressure external to the wellhead. In the case of a surface wellhead it would be 0 psig. In the case of a subsea well head, it would be equal to the hydrostatic pressure of seawater at the depth of the subsea wellhead in psig. Source: API STD 65 – Part 2, Isolating Potential Flow Zones During Well Construction, Upstream Segment, Second Edition, December 2010. Global StandardsAmbient Pressure
“Ambient pressure” means the pressure at any given depth (pression ambiante). Source: Canada Oil and Gas Diving Regulations, SOR/88-600, February 2013. Regulations Source: Nova Scotia Offshore Area Petroleum Diving Regulations, SOR/95-189, Canada, current to May 31, 2012. RegulationsAmbient Temperature
Definition(s)
Ambient Temperature
Prevailing temperature at test site.
Source:API SPECIFICATION 19TT, Specification for Downhole Well Test Tools and Related Equipment, First Edition, October 2016. Global StandardsAmbient Temperature
Actual room temperature in the test lab with no residual heat remaining in test specimens from previous thermal tests. Source: API RP 5C5, Recommended Practice on Procedures for Testing Casing and Tubing Connections, Third Edition, July 2003 (Reaffirmed August 2010). Global StandardsAmbient Temperature
Temperature of the surroundings.. Source: IADC UBO / MPD Glossary, December 2011. Global StandardsAmerican Standard Code for Information Interchange (ASCII)
Definition(s)
American Standard Code for Information Interchange (ASCII)
A different byte represents each number, letter, symbol and punctuation mark. Replaced by Unicode. Source: IADC UBO / MPD Glossary, December 2011. Global StandardsAMMT
Definition(s)
AMMT
American macaroni tubing style of thread design. Source: API SPEC 7-1, Specification for Rotary Drill Stem Elements, First Edition, March 2006 (Addendum April 2011). Global StandardsAmpere
Definition(s)
Ampere (A, I or amp)
Unit of electrical current. Source: API RP 5A5, Field Inspection of New Casing, Tubing, and Plain-end Drill Pipe, Reaffirmed August 2010. Global StandardsAmpere-Turn
Definition(s)
Ampere-Turn
Unit of magnetomotive force which is the product of the number of turns in a coil and the quantity of amperes of current flowing through it, representing the magnetizing strength of the coil. EXAMPLE 800 A in a 6-turn coil gives 4 800 ampere-turns. Source: API RP 5A5, Field Inspection of New Casing, Tubing, and Plain-end Drill Pipe, Reaffirmed August 2010. Global StandardsAmplitude
Definition(s)
Amplitude
Vertical height of the A-scan received signal, measured from base to peak or peak to peak. Source: API SPEC 7-1, Specification for Rotary Drill Stem Elements, First Edition, March 2006 (Addendum April 2011). Global StandardsAMSA
Definition(s)
AMSA
Australian Maritime Safety Authority Source: Rules for Classification and Construction, IV Industrial Services, 6 Offshore Technology, 9 Guideline for Personnel Transfers by Means of Lifting Appliances, Edition 2011, Germanischer Lloyd SE, Global StandardsAMT
Definition(s)
AMT
Alternative abbreviation for the American macaroni tubing style of thread design. Source: API SPEC 7-1, Specification for Rotary Drill Stem Elements, First Edition, March 2006 (Addendum April 2011). Global StandardsAMV
Definition(s)
AMV
Annulus master valve. Source: API RP 17A, Design and Operation of Subsea Production Systems—General Requirements and Recommendations, Fourth Edition, Reaffirmed 2011. Global Standards 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: NORSOK D-010, Well integrity in drilling and well operations, Rev. 3, August 2004. Global StandardsAnalytical Model
Definition(s)
Analytical Model
Algorithm or calculation combining one or more base measures and/or derived measures with associated decision criteria. Source: ISO/IEC 27000:2014, Information technology — Security techniques — Information security management systems — Overview and vocabulary, Third Edition, January 2014. Global StandardsAnalyze
Definition(s)
Analyze
A NICE Workforce Framework category consisting of specialty areas responsible for highly specialized review and evaluation of incoming cybersecurity information to determine its usefulness for intelligence. From: NICE Workforce Framework Source: NICCS™ Portal Cybersecurity Lexicon, National Initiative for Cybersecurity Careers and Studies (https://niccs.us-cert.gov/glossary) as of 11 November 2015, Global StandardsAnchor
Definition(s)
Anchor
“Anchor” means a device that is used to secure, fasten, or stabilize. Source: Oil and Gas Drilling and Servicing Operations, Michigan Administrative Code R 408, February 8, 2013. RegulationsAnchor
Device used to secure items of equipment, important in the context of UBD where vibration is a factor or concern. Source: IADC UBO / MPD Glossary, December 2011. Global StandardsAnchor Base
Definition(s)
Anchor Base
Structure used to secure one end of a tether to the seabed. Source: API RP 17L2, Recommended Practice for Flexible Pipe Ancillary Equipment, First Edition, March 2013. Global StandardsAnchor Base
Structure used to secure one end of a tether to the seabed. Source: API SPEC 17L1, Specification for Flexible Pipe Ancillary Equipment, First Edition, March 2013. Global StandardsAncillary Component
Definition(s)
Ancillary component
Component that is attached to the flexible pipe in order to perform one or more of the following functions:- to control the flexible pipe behavior;
- to provide a structural transition between the flexible pipe and adjacent structures;
- to attach other structures to the flexible pipe;
- to protect or repair the flexible pipe;
- to provide a seal along the flexible pipe length.
Ancillary Components
Definition(s)
Ancillary Components
Components used to control the flexible pipe behaviour, such as bend stiffeners and buoyancy modules. Source: API SPEC 17J, Specification for Unbonded Flexible Pipe, Third Edition, July 2008. Global StandardsAncillary Equipment
Definition(s)
Ancillary Equipment
Accessory to the umbilical system that does not form part of the main functional purpose. EXAMPLES Weak link, buoyancy attachments, I-tube or J-tube seals, VIV strakes, centralizers, anchors external clamps. Source: API SPEC 17E, Specification for Subsea Umbilicals, Upstream Segment, Fourth Edition, October 2010. Global StandardsAngle Beam
Definition(s)
Angle Beam
Term used to describe an angle of incidence or refraction other than normal to the surface of the test object. This includes shear waves and longitudinal (compression) waves. Source: API RP 5A5, Field Inspection of New Casing, Tubing, and Plain-end Drill Pipe, Reaffirmed August 2010. Global StandardsAniline Point
Definition(s)
Aniline Point
The aromatics content of a hydrocarbon mixture. Source: IADC UBO / MPD Glossary, December 2011. Global StandardsAnisotropic
Definition(s)
Anisotropic
Exhibiting different properties when tested along axes in different directions.Source: ISO 14692-1:2017, Petroleum and natural gas industries — Glass-reinforced plastics (GRP) piping — Part 1: Vocabulary, symbols, applications and materials, Second Edition, August 2017. Global Standards
Anistropic Material
Definition(s)
Anistropic Material
A material for which properties vary with changes in test direction relative to an initial datum.
Source:API SPECIFICATION 7K, Drilling and Well Servicing Equipment, Sixth Edition, December 2015. Global StandardsAnniversary Date
Definition(s)
Anniversary date
Anniversary date means the day and the month of each year, which corresponds to the date of expiration of the Certificate of Inspection. Source: Mobile Offshore Drilling Units, 46 CFR 107-109 (2013). RegulationsAnniversary date
Anniversary date means the day and month of each year which will correspond to the date of expiry of the certificate. Source: IMO Resolution A.1023(26), Code for the Construction and Equipment of Mobile Offshore Drilling Units (2009 MODU Code), 2009. Global Standards Source: International Convention for the Control and Management of Ships’ Ballast Water and Sediments, 2004, LegislationAnniversary date
Anniversary date means the day and the month of each year which will correspond to the date of expiry of the International Pollution Prevention Certificate for the Carriage of Noxious Liquid Substances in Bulk. <Annex II, Chapter 1, Regulation 1>. Source: Source: Resolution MEPC.118(52), amendments to the Annex of the Protocol of 1978 relating to the International Convention for the Prevention of Pollution from Ships, 1973 (Revised Annex II of MARPOL 73/78), 15 October 2004, International Maritime Organization. LegislationAnniversary date
Anniversary date means the day and the month of each year which will correspond to the date of expiry of the International Air Pollution Prevention Certificate. <Annex VI, regulation 2>. Source: Source: Resolution MEPC.118(52), amendments to the Annex of the Protocol of 1978 relating to the International Convention for the Prevention of Pollution from Ships, 1973 (Revised Annex II of MARPOL 73/78), 15 October 2004, International Maritime Organization. Legislation Source: Resolution MEPC.176(58), amendments to the Annex of the Protocol of 1978 relating to the International Convention for the Prevention of Pollution from Ships (Revised MARPOL Annex VI), 10 October 2008, International Maritime Organization. LegislationAnniversary Date
Anniversary date means the day and month of each year that corresponds to the date of expiry of the relevant document or certificate. Source: IMO Resolution MSC.104(73), amendments to the International Management Code for the Safe Operation of Ships and for Pollution Prevention (International Safety Management (ISM) Code), 5 December 2000, International Maritime Organization. LegislationAnnual BOP
Definition(s)
Annual BOP
Blowout preventer that uses an annular shaped elastomeric sealing element to seal the space between the tubular and the wellbore or an open hole.
Source: API STANDARD 16AR, Standard for Repair and Remanufacture of Drill-through Equipment, First Edition, April 2017. Global Standards