Glossary
Browse the IADC Lexicon alphabetically or by category. Get comprehensive definitions of drilling industry terms.
UDP
Definition(s)
UDP
Used Drill Pipe. Source: API RP 7G-2, Recommended Practice for Inspection and Classification of Used Drill Stem Elements, First Edition, August 2009. Global StandardsUDP
User Datagram Protocol. Source: ISO/IEC 27032:2015, Information technology — Security techniques — Guidelines for cybersecurity, First Edition, July 2012. Global StandardsTPR
Definition(s)
TPR
Taper. Source: API RP 7G-2, Recommended Practice for Inspection and Classification of Used Drill Stem Elements, First Edition, August 2009. Global StandardsTJ
Definition(s)
TJ
Tool joint. Source: API RP 7G-2, Recommended Practice for Inspection and Classification of Used Drill Stem Elements, First Edition, August 2009. Global StandardsTJ
Telescopic joint. Source: Deepwater Well Control Guidelines. IADC GuidelinesPPGE
Definition(s)
PPGE
Pounds per gallon equivalent density. Source: API STD 65 – Part 2, Isolating Potential Flow Zones During Well Construction, Upstream Segment, Second Edition, December 2010. Global StandardsSWBM
Definition(s)
SWBM
Synthetic water-based mud. Source: API RP 7G-2, Recommended Practice for Inspection and Classification of Used Drill Stem Elements, First Edition, August 2009. Global StandardsPotential Flow Zone
Definition(s)
Potential Flow Zone
Any zone in a well where flow is possible under when wellbore pressure is less than pore pressure. Source: API STD 65 – Part 2, Isolating Potential Flow Zones During Well Construction, Upstream Segment, Second Edition, December 2010. Global StandardsPotential Flow Zone
“Potential flow zone” means any zone in a well where hydrocarbons or other fluids can flow when wellbore pressure is less than pore pressure and isolation of such zones is necessary to: (a) Isolate hydrocarbons that may be present in testable or commercial quantities; (b) Prevent over-pressurization of the surface casing annulus; or (c) Maintain well control when drilling on fluid below the zone. Source: Division of Mineral Resources Management - Oil and Gas, Ohio Administrative Code, Chapter 1501:9, January 2012. RegulationsPore Pressure (PP)
Definition(s)
Pore Pressure (PP)
Pore pressure is the pressure of the fluid inside the pore spaces of a formation. Source: API STD 65 – Part 2, Isolating Potential Flow Zones During Well Construction, Upstream Segment, Second Edition, December 2010. Global StandardsPore Pressure (formation pressure)
Pressure exerted by the fluids within the pore space of a formation. Source: API RP 59, Recommended Practice for Well Control Operations, Second Edition, May 2006. Global StandardsPore Pressure
Pressure exerted by fluids in a formation pore space. Source: IADC UBO / MPD Glossary, December 2011. Global StandardsPore Pressure
The amount of force that is being exerted into the borehole by fluids or gases within the formation that has been penetrated. Source: NOGEPA Industrial Guideline No. 43, Surface BOP Review, Best Practices Checklist, Netherlands, Version 0, December 2011. Global StandardsSOBM
Definition(s)
SOBM
Synthetic oil-based mud. Source: API RP 7G-2, Recommended Practice for Inspection and Classification of Used Drill Stem Elements, First Edition, August 2009. Global StandardsS/N
Definition(s)
S/N
Signal-to-noise ratio. Source: API RP 7G-2, Recommended Practice for Inspection and Classification of Used Drill Stem Elements, First Edition, August 2009. Global StandardsPolished Bore Receptacle (PBR)
Definition(s)
Polished Bore Receptacle (PBR)
A device with a honed internal diameter (ID) sealing surface for landing a production tubing seal assembly or tie back casing. Source: API STD 65 – Part 2, Isolating Potential Flow Zones During Well Construction, Upstream Segment, Second Edition, December 2010. Global StandardsPhysical Barrier Element
Definition(s)
Physical Barrier Element
Physical barrier elements can be classified as hydrostatic, mechanical or solidified chemical materials (usually cement). Source: API STD 65 – Part 2, Isolating Potential Flow Zones During Well Construction, Upstream Segment, Second Edition, December 2010. Global StandardsPBR
Definition(s)
PBR
Polished bore receptacle. Source: API STD 65 – Part 2, Isolating Potential Flow Zones During Well Construction, Upstream Segment, Second Edition, December 2010. Global StandardsOverbalance Pressure (OBP)
Definition(s)
Overbalance Pressure (OBP)
Overbalance pressure is the amount by which the hydrostatic pressure exceeds the pore pressure of a formation. Source: API STD 65 – Part 2, Isolating Potential Flow Zones During Well Construction, Upstream Segment, Second Edition, December 2010. Global StandardsOBP
Definition(s)
OBP
Over balanced pressure. Source: API STD 65 – Part 2, Isolating Potential Flow Zones During Well Construction, Upstream Segment, Second Edition, December 2010. Global StandardsOBM
Definition(s)
OBM
Oil-based mud. Source: API RP 7G-2, Recommended Practice for Inspection and Classification of Used Drill Stem Elements, First Edition, August 2009. Global Standards Source: OGP Report No. 476, Recommendations for enhancements to well control training, examination and certification, International Association of Oil & Gas Producers, October 2012. Global StandardsNI
Definition(s)
NI
Calculated number of cycles to failure at a constant stress range. Source: API Technical Report 17TR7, Verification and Validation of Subsea Connectors, First Edition, April 2017. Global StandardsNI
Ampere turns. Source: API RP 7G-2, Recommended Practice for Inspection and Classification of Used Drill Stem Elements, First Edition, August 2009. Global StandardsOperator Imposed Casing Pressure
Definition(s)
Operator Imposed Casing Pressure
Pressure in a casing that is operator imposed for purposes such as casing pressure integrity tests (prior to drilling out the shoe), gas lift, fluid injection, stimulation treatments, thermal insulation, etc. Source: API STD 65 – Part 2, Isolating Potential Flow Zones During Well Construction, Upstream Segment, Second Edition, December 2010. Global StandardsOperator Imposed Casing Pressure
Casing pressure that is operator-imposed for purposes such as gas lift, water injection, thermal insulation, etc. Source: API RP 90, Annular Casing Pressure Management for Offshore Wells, Upstream Segment. First Edition, August 2006. Global StandardsMWD
Definition(s)
MWD
Measuring while drilling. Source: API RP 7G-2, Recommended Practice for Inspection and Classification of Used Drill Stem Elements, First Edition, August 2009. Global Standards Source: Deepwater Well Control Guidelines. IADC GuidelinesMWD/LWD
Management while drilling / logging while drilling. Source: OGP Report No. 476, Recommendations for enhancements to well control training, examination and certification, International Association of Oil & Gas Producers, October 2012. Global StandardsMWD
Measurement While Drilling. Source: NOGEPA Industrial Guideline No. 41, Well Construction Process Checklist, Drilling Best Practices, Netherlands, Version 0, December 2011. Global Standards Source: NORSOK D-001, Drilling facilities, Rev. 3, December 2012. Global StandardsNon-Aqueous Fluid (NAF)
Definition(s)
Non-Aqueous Fluid (NAF)
Non-aqueous fluid is a non-aqueous drilling fluid or well circulating fluid. Common NAF systems are diesel, mineral oil, or synthetic fluid based invert emulsions, or other non water based fluids. Source: API STD 65 – Part 2, Isolating Potential Flow Zones During Well Construction, Upstream Segment, Second Edition, December 2010. Global StandardsLWD
Definition(s)
LWD
Logging while drilling. Source: API RP 7G-2, Recommended Practice for Inspection and Classification of Used Drill Stem Elements, First Edition, August 2009. Global Standards Source: Deep Water Well Control Guidlines. IADC Guidelines Source: NOGEPA Industrial Guideline No. 41, Well Construction Process Checklist, Drilling Best Practices, Netherlands, Version 0, December 2011. Global Standards Source: NORSOK D-010, Well integrity in drilling and well operations, Rev. 3, August 2004. Global StandardsMWD/LWD
Management while drilling / logging while drilling. Source: OGP Report No. 476, Recommendations for enhancements to well control training, examination and certification, International Association of Oil & Gas Producers, October 2012. Global StandardsLT
Definition(s)
LT
Low torque. Source: API RP 7G-2, Recommended Practice for Inspection and Classification of Used Drill Stem Elements, First Edition, August 2009. Global StandardsNippling Up
Definition(s)
Nippling Up
The process of installing well-control or pressure-control equipment such as a BOP system. Source: API STD 65 – Part 2, Isolating Potential Flow Zones During Well Construction, Upstream Segment, Second Edition, December 2010. Global StandardsHWDP
Definition(s)
HWDP
Heavy-weight drill pipe. Source: API RP 7G-2, Recommended Practice for Inspection and Classification of Used Drill Stem Elements, First Edition, August 2009. Global StandardsHWAC
Definition(s)
HWAC
Half-wave alternating current. Source: API RP 7G-2, Recommended Practice for Inspection and Classification of Used Drill Stem Elements, First Edition, August 2009. Global StandardsFWAC
Definition(s)
FWAC
Full-wave rectified alternating current. Source: API RP 7G-2, Recommended Practice for Inspection and Classification of Used Drill Stem Elements, First Edition, August 2009. Global StandardsFSH
Definition(s)
FSH
Full screen height. Source: API RP 7G-2, Recommended Practice for Inspection and Classification of Used Drill Stem Elements, First Edition, August 2009. Global StandardsFLUT
Definition(s)
FLUT
Full-length ultrasonic transverse. Source: API RP 7G-2, Recommended Practice for Inspection and Classification of Used Drill Stem Elements, First Edition, August 2009. Global StandardsFF
Definition(s)
Ff
Primary structure design load due to forklift operation.
Source: API Standard 2CCU, Offshore Cargo Carrying Units, First Edition, August 2017. Global Standards