Glossary
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DAF
Definition(s)
DAF
Ratio of a dynamic action effect to the corresponding static action effect. NOTE 1 For a jack-up, the dynamic action effect is best simulated by means of a concentrated or distributed inertial loadset. It is usually not appropriate to factor the static actions to simulate the effects of dynamic actions. NOTE 2 The DAF excluding the mean values, KDAF,SDOF, can typically be obtained from a single degree-of-freedom (SDOF) calculation. In this case, it is defined as the ratio of the amplitude of a dynamic action effect to the amplitude of the corresponding static action effect for periodic excitation of a linear one degree-of-freedom model approximation of jack-up behaviour. NOTE 3 The DAF including the mean values, KDAF,RANDOM, can typically be obtained from a random wave calculation. In this case, it is defined as the ratio of the absolute value of a dynamic action effect to the absolute value of the corresponding static action effect, each including their mean value. NOTE 4 Adapted from ISO 19902:2007, definition 3.16. Source: ISO 19905-1:202, Petroleum and natural gas industries – Site-specific assessment of mobile offshore units – Part 1: Jack-ups. Global StandardsDAF
Dynamic amplification factor. Source: ISO 19905-1:202, Petroleum and natural gas industries – Site-specific assessment of mobile offshore units – Part 1: Jack-ups. Global StandardsDynamic Amplification Factor
Definition(s)
Dynamic Amplification Factor
Ratio of a dynamic action effect to the corresponding static action effect. NOTE 1 For a jack-up, the dynamic action effect is best simulated by means of a concentrated or distributed inertial loadset. It is usually not appropriate to factor the static actions to simulate the effects of dynamic actions. NOTE 2 The DAF excluding the mean values, KDAF,SDOF, can typically be obtained from a single degree-of-freedom (SDOF) calculation. In this case, it is defined as the ratio of the amplitude of a dynamic action effect to the amplitude of the corresponding static action effect for periodic excitation of a linear one degree-of-freedom model approximation of jack-up behaviour. NOTE 3 The DAF including the mean values, KDAF,RANDOM, can typically be obtained from a random wave calculation. In this case, it is defined as the ratio of the absolute value of a dynamic action effect to the absolute value of the corresponding static action effect, each including their mean value. NOTE 4 Adapted from ISO 19902:2007, definition 3.16. Source: ISO 19905-1:202, Petroleum and natural gas industries – Site-specific assessment of mobile offshore units – Part 1: Jack-ups. Global StandardsConsequence Category
Definition(s)
Consequence Category
classification system for identifying the environmental, economic, and indirect personnel safety consequences of failure of a platform. Source: ISO 19900:2013, Petroleum and natural gas industries – General requirements for offshore structures. Global StandardsConsequence Category
Classification system for identifying the environmental, economic and indirect personnel safety consequences of failure of a jack-up. NOTE 1 Categories for environmental and economic consequences are the following (see 5.3.3): – C1: high environmental or economic consequence; – C2: medium environmental or economic consequence; – C3: low environmental or economic consequence. NOTE 2 Adapted from ISO 19902:2007, definition 3.11. Source: ISO 19905-1:202, Petroleum and natural gas industries – Site-specific assessment of mobile offshore units – Part 1: Jack-ups. Global StandardsChart Datum
Definition(s)
Chart Datum
local datum used to fix water depths on a chart or tidal heights over an area NOTE Chart datum is usually an approximation to the level of the lowest astronomical tide. Source: API RP 2MET, Derivation of Metocean Design and Operating Conditions, First Edition, November 2014. Global StandardsChart Datum
Local datum used to fix water depths on a chart or tidal heights over an area. NOTE Chart datum is usually an approximation to the level of the lowest astronomical tide.[ISO 19901-1:2005, definition 3.2]. Source: ISO 19905-1:202, Petroleum and natural gas industries – Site-specific assessment of mobile offshore units – Part 1: Jack-ups. Global StandardsBoundary Conditions
Definition(s)
Boundary Conditions
Actions and constraints on a (section of a) structural component (or a group of structural components) by other structural components or by the environment surrounding it. NOTE Boundary conditions can be used to generate reaction forces at locations of restraint. [ISO 19902:2007, definition 3.6]. Source: ISO 19905-1:202, Petroleum and natural gas industries – Site-specific assessment of mobile offshore units – Part 1: Jack-ups. Global StandardsBackflow
Definition(s)
Backflow
Soil flows from bottom of spudcan back into the cavity on the exposed top of the spudcan.
Source: ABS Guidance Notes on Geotechnical Performance of Spudcan Foundations, January 2017. Global StandardsBackflow
Soil that flows from beneath the spudcan around the sides and onto the top. NOTE Backflow is part of backfill (3.7). Source: ISO 19905-1:202, Petroleum and natural gas industries – Site-specific assessment of mobile offshore units – Part 1: Jack-ups. Global StandardsBackfill
Definition(s)
Backfill
Soil material used to refill the cavity above the spudcan due to spudcan penetration.
Source: ABS Guidance Notes on Geotechnical Performance of Spudcan Foundations, January 2017. Global StandardsBackfill
Submerged weight of all of the soil that can be present on top of the spudcan. NOTE Backfilling can occur during or after preloading. WBF,o refers to the submerged weight of the backfilling that occurs up to achieving the preload reaction. WBF,A refers to the submerged weight of the backfilling that occurs after the maximum preload has been applied and held. Both WBF,o and WBF,A can comprise backflow and/or infill. For discussion of the effects, see A.9.3.2.1.4. Source: ISO 19905-1:202, Petroleum and natural gas industries – Site-specific assessment of mobile offshore units – Part 1: Jack-ups. Global StandardsAssessment Situation
Definition(s)
Assessment Situation
Jack-up configuration together with the environmental loading to be assessed. NOTE 1 For discussion on configuration, see 5.4.1. NOTE 2 The assessment situations are checked against the acceptance criteria of this part of ISO 19905 to demonstrate that the relevant limit states are not exceeded. Source: ISO 19905-1:202, Petroleum and natural gas industries – Site-specific assessment of mobile offshore units – Part 1: Jack-ups. Global StandardsAccidental Situation
Definition(s)
Accidental Situation
Design situation involving exceptional conditions of the structure or its exposure.- EXAMPLE Impact, fire, explosion, loss of intended differential pressure).
Accidental Situation
Exceptional situation of the structure. EXAMPLE Impact; fire; explosion; local failure; loss of intended differential pressure (e.g. buoyancy). Source: ISO 19905-1:202, Petroleum and natural gas industries – Site-specific assessment of mobile offshore units – Part 1: Jack-ups. Global StandardsAbnormal Wave Crest
Definition(s)
Abnormal Wave Crest
Wave crest with probability of typically 10-3 to 10-4 per annum. Source: ISO 19905-1:202, Petroleum and natural gas industries – Site-specific assessment of mobile offshore units – Part 1: Jack-ups. Global StandardsBattery
Definition(s)
Battery
BATTERY shall mean the point of collection (tanks) and disbursement (tank, meter, LACT unit) of oil or gas from producing well(s). Source: Oil and Gas Conservation Commission, Practice and Procedure, Code of Colorado Regulations, 2 CCR 404-1, February 2013. RegulationsBattery
Equipment used to process or store crude oil from one or more wells. Source: IADC UBO / MPD Glossary, December 2011. Global StandardsAquifer
Definition(s)
Aquifer
"Aquifer" means a geological formation, group of formations, or part of a formation that is capable of yielding a significant amount of water to a well or spring. Source: Corporation Commission, Oil and Gas Conservation, Oklahoma Administrative Code 165:10, February 2013. RegulationsAquifer
“Aquifer” means a geological formation, group of formations, or part of a formation that is capable of yielding a significant amount of water to a well or spring. Source: Division of Mineral Resources Management - Oil and Gas, Ohio Administrative Code, Chapter 1501:9, January 2012. RegulationsAquifer
A subsurface formation that is sufficiently permeable to hold and conduct groundwater and to yield economically significant quantities of water to wells and springs. Source: Identifying and assessing water sources: Guidance document for the onshore oil and gas industry, International Petroleum Industry Environmental Conservation Association (IPIECA), 2014. Global StandardsAquifer
AQUIFER shall mean a geologic formation, group of formations or part of a formation that can both store and transmit ground water. It includes both the saturated and unsaturated zone but does not include the confining layer which separates two (2) adjacent aquifers. Source: Oil and Gas Conservation Commission, Practice and Procedure, Code of Colorado Regulations, 2 CCR 404-1, February 2013. RegulationsAquifer
“Aquifer” means a geological formation, group of formations or a part of a formation that is capable of yielding a significant amount of water to a well or spring. Source: Oil and Gas, New Mexico Administrative Code Title 19, Chapter 15, January 2013. RegulationsValve
Definition(s)
Valve
Device used to stop or control the rate of flow in a line or vessel or to serve as an automatic or semiautomatic safety device. Common valves include the butterfly, gate, plug, globe, needle, check, and pressure relief. Source: IADC UBO / MPD Glossary, December 2011. Global StandardsValve
A device for regulating or controlling the flow of material by means of a movable part or parts which open or close a passage. Source: Petroleum Safety Orders--Drilling and Production, Definitions, California Code of Regulations, 8 CCR § 6505, December 2012. RegulationsRemote Control
Definition(s)
Remote Control
Line or vessel control achieved at a remote control center using a SCADA system. Source: IADC UBO / MPD Glossary, December 2011. Global StandardsRemote Control
A wired or wireless equipment control device that operates the diesel engine's air intake shut-off valve from a distance. Source: Petroleum Safety Orders--Drilling and Production, Definitions, California Code of Regulations, 8 CCR § 6505, December 2012. RegulationsWEC
Definition(s)
WEC
Wells Expert Committee. Source: OGP Report No. 476, Recommendations for enhancements to well control training, examination and certification, International Association of Oil & Gas Producers, October 2012. Global StandardsWCTEC
Definition(s)
WCTEC
Well Control Training, Examination and Certification. Source: OGP Report No. 476, Recommendations for enhancements to well control training, examination and certification, International Association of Oil & Gas Producers, October 2012. Global StandardsU-tube
Definition(s)
U-tube
Method to assimilate pressures between two vertical pipes with pressure communicating at the bottom but potentially filled with different fluid densities and possibly having different pressures applied at different points in the pipes. Source: OGP Report No. 476, Recommendations for enhancements to well control training, examination and certification, International Association of Oil & Gas Producers, October 2012. Global StandardsUBD
Definition(s)
UBD
Underbalanced 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 Standards Source: NORSOK D-001, Drilling facilities, Rev. 3, December 2012. Global Standards Source: Oil & Gas UK, Guidelines on subsea BOP systems, Issue 1, July 2012, Global StandardsPressure Operations
Definition(s)
Pressure operations
Well operations where any of the following conditions exist: the wellbore hydraulic fluid column is not expected to contain formation pressure, if well kill operations are anticipated or if surface pressure control equipment is required during a well operation. Source: OGP Report No. 476, Recommendations for enhancements to well control training, examination and certification, International Association of Oil & Gas Producers, October 2012. Global StandardsOperations Team
Definition(s)
Operations Team(s)
Well operations personnel from oil and gas producing companies, but also for all critical well operations personnel including drilling contractors, well intervention and well servicing companies, covering both wellsite and office-based personnel. Specific roles within an Operations Team are described in more detail in the Role based Training section of this document. Source: OGP Report No. 476, Recommendations for enhancements to well control training, examination and certification, International Association of Oil & Gas Producers, October 2012. Global StandardsNon Pressure Operations
Definition(s)
Non Pressure Operations
Well operations whereby: the wellbore hydraulic fluid column is expected to control the wellbore pressure, well control equipment is expected to be used only as a secondary barrier and no well kill operations are anticipated. 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/LWD
Definition(s)
MWD/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 StandardsIWCF
Definition(s)
IWCF
International Well Control Forum. Source: OGP Report No. 476, Recommendations for enhancements to well control training, examination and certification, International Association of Oil & Gas Producers, October 2012. Global StandardsHT
Definition(s)
HT
High temperature is defined as when the undisturbed bottom hole temperature at reservoir depth is greater than 149°C (300°F). Source: OGP Report No. 476, Recommendations for enhancements to well control training, examination and certification, International Association of Oil & Gas Producers, October 2012. Global Standardsht
Height of spudcan widest diameter.
Source: ABS Guidance Notes on Geotechnical Performance of Spudcan Foundations, January 2017. Global Standards