Glossary
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Well Examination
Definition(s)
Well Examination
Well Examination is an independent assurance process on behalf of the Well Operator to ensure that the pressure boundary of the well is controlled throughout its life and the pressure-containment equipment that forms part of the well is suitable for this purpose. Source: NOGEPA Industrial Guideline No. 42, Well Plan Review, “Well Examination Scheme for The Netherlands,” Netherlands, Version 0, December 2011. Global StandardsWell Examination Scheme
Definition(s)
Well Examination Scheme
In this regulation, well examination scheme means arrangements for examinations of the well that are— (a) recorded in writing; and (b) suitable for ensuring (together with the assistance of any other measures the well operator may take) that the well is designed, constructed, operated, maintained, modified, suspended, and abandoned so that,— (i) so far as is reasonably practicable, there can be no unplanned escape of fluids from the well; and (ii) risks to the health and safety of persons from the well or anything in it, or from strata to which the well is connected, are as low as is reasonably practicable; and (c) conducted by an independent and competent person. Source: Health and Safety in Employment (Petroleum Exploration and Extraction) Regulations 2013, SR 2013/208, New Zealand, as of May 2013. RegulationsWell Handover
Definition(s)
Well Handover
Act or process that formalises the transfer of a well, and operating responsibility, from one competent party to another, including the requisite data and documents. Source: ISO 16530-1:2017, Petroleum and natural gas industries — Well integrity – Part 1: Life cycle governance, First Edition, March 2017. Global StandardsWell Integrity
Definition(s)
Well Integrity
Containment and prevention of the escape of fluids to subterranean formations or surface.
Source: ISO 16530-1:2017, Petroleum and natural gas industries — Well integrity – Part 1: Life cycle governance, First Edition, March 2017. Global StandardsWell Integrity
Application of technical, operational and organizational solutions to reduce risk of uncontrolled release of formation fluids throughout the life cycle of a well. Source: API RP 90, Annular Casing Pressure Management for Offshore Wells, Upstream Segment. First Edition, August 2006. Global StandardsWell Integrity
“Well integrity” means the quality or condition of a well being structurally sound with competent pressure seals by the application of technical and operational solutions that prevent uncontrolled fluid release or migration of annular fluids into protected groundwater throughout the well life cycle. Source: Division of Mineral Resources Management - Oil and Gas, Ohio Administrative Code, Chapter 1501:9, January 2012. RegulationsWell Integrity Management
Definition(s)
Well Integrity Management
Application of technical, operational and organizational methods to prevent the uncontrolled flow of fluids at the surface or across subsurface formations throughout the life cycle of the well. Source: ISO 16530-1:2017, Petroleum and natural gas industries — Well integrity – Part 1: Life cycle governance, First Edition, March 2017. Global StandardsWell Intervention Operation
Definition(s)
Well Intervention Operation
Well intervention operation is well servicing operations conducted within a completed wellbore.
Source: Norwegian Oil and Gas Association, Guideline No. 135, Recommended Guidelines for Classification and categorization of well control incidents and well integrity incidents, Rev. 4, 27 June 2017, National or Regional StandardsWell Intervention Operation
An operation in which a well is re-entered for a purpose other than to continue drilling or to maintain or repair it. Regulation 2, DCR. Source: Oil & Gas UK, Guidelines on subsea BOP systems, Issue 1, July 2012, Global StandardsWell Logging Module
Definition(s)
Well Logging Module
Modularized facilities that include well logging winch, well logging room, wellhead lubricator and cable, used to provide well logging services. Source: ISO 18647:2017, Petroleum and natural gas industries — Modular drilling rigs for offshore fixed platforms, First Edition, August 2017. Global StandardsWell Monitoring Programs
Definition(s)
Well Monitoring Programs
The API inactive well program describes monitoring that could be used by an operator for wells in the four fluid migration potential categories. The well monitoring program requirements and monitoring frequencies increase as the fluid migration potential increases. Source: API BULLETIN E3, Environmental Guidance Document: Well Abandonment and Inactive Well Practices for U.S. Exploration and Production Operations, First Edition, January 1993 (Reaffirmed June 2000). Global StandardsWell Operating Limits
Definition(s)
Well Operating Limits
Combination of parameters established by the well operator within which the well should be operated to ensure that all component specifications, including their applicable design or safety factors and performance standards, are not violated throughout the well life cycle. Source: ISO 16530-1:2017, Petroleum and natural gas industries — Well integrity – Part 1: Life cycle governance, First Edition, March 2017. Global StandardsWell Operating Limits
The well operating limits are defined as the combination of parameters within which the well should be operated to ensure that all component specifications, including their applicable design or safety factors and performance standards, are not violated. Source: ISO 16530-1:2017, Petroleum and natural gas industries — Well integrity – Part 1: Life cycle governance, First Edition, March 2017. Global StandardsWell Operator
Definition(s)
Well Operator
Company that has responsibility for the well. Source: ISO 16530-1:2017, Petroleum and natural gas industries — Well integrity – Part 1: Life cycle governance, First Edition, March 2017. Global StandardsWell Operator
Well operator or operator—The person designated as the well operator or operator on the permit application or well registration. If a permit or registration was not issued, the term means a person who locates, drills, operates, alters or plugs a well or reconditions a well with the purpose of production therefrom. In cases where a well is used in connection with the underground storage of gas, the term also means a storage operator. Source: Oil and Gas Wells, Pennsylvania Code, Title 25, Chapter 78, December 2012. RegulationsWell Operator
"Well operator" means a person as herein defined who has the responsibility, management, and general control of an oil or gas well, or lessee, sub-lessee, owner or assignee of same. Source: State of Wyoming Occupational Safety and Health Rules and Regulations for Oil and Gas Well Drilling, Revised January 8, 2013. RegulationsWell Operator
“well operator”, in relation to a well or proposed well, means—- the person appointed by the licensee for that well or proposed well to execute the function of organising and supervising the drilling of that well and all operations to be carried out by means of that well; or
- where no such person has been appointed, the licensee.
Well Operator
Well operator, in relation to a well or proposed well, means— (a) the employer appointed by the permit operator to perform the function of organising and supervising— (i) the drilling of that well; and (ii) all operations to be carried out by means of that well; or (b) the permit operator, if the permit operator is an employer of employees at the well site and— (i) no employer is appointed; or (ii) the permit operator has notified the appointed employer in writing that the permit operator is to be treated as the well operator for the purposes of these regulations. Source: Health and Safety in Employment (Petroleum Exploration and Extraction) Regulations 2013, SR 2013/208, New Zealand, as of May 2013. RegulationsWell Plan
Definition(s)
Well Plan
Lease operator's documentation of the planned well construction activities. Source: API Bulletin 97, Well Construction Interface Document Guidelines, First Edition, December 2013. Global StandardsWell Servicing
Definition(s)
Well Servicing
Well work involving pulling or running tubulars or sucker rods, to include but not limited to redrilling, completing, recompleting, workover, and abandoning operations. Source: API RP 74, Recommended Practice for Occupational Safety for Onshore Oil and Gas Production Operation, First Edition, October 2001 (March 2007). Global StandardsWell Servicing
Remedial or maintenance work performed within the well casing on any well, other than a drilling well. Source: Petroleum Safety Orders--Drilling and Production, Definitions, California Code of Regulations, 8 CCR § 6505, December 2012. RegulationsWell Servicing
“Well servicing” means the remedial or maintenance work performed on an oil or gas well to improve or maintain the production from a formation already producing. [Mich. Admin. Code R 408 (2013)]. Source: Oil and Gas Drilling and Servicing Operations, Michigan Administrative Code R 408, February 8, 2013. RegulationsWell Servicing Rig
Definition(s)
Well Servicing Rig
Equipment and machinery assembled primarily for the purpose of any well work involving pulling or running tubulars or sucker rods, to include but not be limited to redrilling, completing, recompleting, workover, and abandoning operations. Source: API RP 54, Recommended Practice for Occupational Safety for Oil and Gas Well Drilling and Servicing Operations, Third Edition, August 1999 (2007). Global StandardsWell Servicing Rig
“Well servicing rig” means a portable rig consisting of a hoist, engine, and a self-erecting mast. [Mich. Admin. Code R 408 (2013)]. Source: Oil and Gas Drilling and Servicing Operations, Michigan Administrative Code R 408, February 8, 2013. RegulationsWell Simulation Test
Definition(s)
Well Simulation Test
Test whose parameters are designed and modified as required to simulate the conditions found in a wellbore. Source: API RP 10B-2, Recommended Practice for Testing Well Cements, First Edition, July 2005 (Reaffirmed: July 2010). Global StandardsWell Slot
Definition(s)
Well Slot
Opening provided for individual wells that allows a path from the underside of the drilling equipment set to the seabed- Note: 1 to entry: In general lateral supports are provided below each well slot from the platform structure through the topsides and through the water column to support the well tubular to withstand environmental forces and prevent excessive stress and displacements.
Well Spacer/tie-back Template
Definition(s)
Well spacer/tie-back template
A well spacer/tie-back template is a multiwell template used as a drilling guide to predrill wells at a single seabed location. Often this type of template is used prior to installing a surface facility above the template to which the wells are subsequently tied back (see Figure A.19). The wells can also be completed using subsea trees and individual production risers from each subsea tree, tied back to a floating or fixed host facility located above the template. Alternatively, a manifold may be subsequently landed on the template, thus effectively converting this system into a multiwell manifold template, as described further below. Source: API RP 17A, Design and Operation of Subsea Production Systems—General Requirements and Recommendations, Fourth Edition, Reaffirmed 2011. Global StandardsWell Status
Definition(s)
Well Status
Well’s current operational function.- Note: 1 to entry: Functions include undergoing construction, in operation (i.e. producing, injecting, shut-in), undergoing intervention, suspended, or abandoned.
Well Stock
Definition(s)
Well Stock
Portfolio of wells for which the well operator has operating or well integrity assurance responsibility. Source: ISO 16530-1:2017, Petroleum and natural gas industries — Well integrity – Part 1: Life cycle governance, First Edition, March 2017. Global StandardsWell 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 GuidanceWell Testing Packer
Definition(s)
Well Testing Packer
A sealing and load-bearing device that isolates the formation from annulus fluids and conforms to Annex E.
Source:API SPECIFICATION 19TT, Specification for Downhole Well Test Tools and Related Equipment, First Edition, October 2016. Global StandardsWell Testing Safety Valve
Definition(s)
Well Testing Safety Valve
A downhole device that is designed to close, typically with annulus overpressure, to isolate the formation from the work string.
Source:API SPECIFICATION 19TT, Specification for Downhole Well Test Tools and Related Equipment, First Edition, October 2016. 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 StandardsWell-being
Definition(s)
Well-being
<work system> sustainable internal state resulting from satisfaction of the physical and cognitive needs of the worker (2.4) during his/her activity.- Note 1 to entry: Well-being can contribute to the quality of working life.
Well-Completion Equipment
Definition(s)
Well-Completion Equipment
Well-completion equipment in this context refers to equipment below wellhead level. All major completion equipment items are included, from tubing hanger at the top end to equipment at the bottom of the well. Source: API STD 689, Collection and Exchange of Reliability and Maintenance Data for Equipment, First Edition, July 2007. Global StandardsWell-Contoured
Definition(s)
Well-Contoured
Because of the difficulty in defining "well-contoured" and "high degree of workmanship", the owner's discretion shall govern (only with respect to the contour of the grind). Source: API RP 5A5, Field Inspection of New Casing, Tubing, and Plain-end Drill Pipe, Reaffirmed August 2010. Global StandardsWell-examiner
Definition(s)
Well-examiner
In this document “well-examiner” covers any individual team, department or company providing well examination services as described by Regulation 18, DCR. Source: Oil & Gas UK, Guidelines on subsea BOP systems, Issue 1, July 2012, Global StandardsWellbore
Definition(s)
Wellbore
The interior surface of the cased or openhole through which drilling, production, or injection operations are conducted. Source: API BULLETIN E3, Environmental Guidance Document: Well Abandonment and Inactive Well Practices for U.S. Exploration and Production Operations, First Edition, January 1993 (Reaffirmed June 2000). Global StandardsWellhead
Definition(s)
Wellhead
The point at which fluids exit the wellbore below the annular sealing device via the vent line. Source: API RP 64, Recommended Practice for Diverter Systems Equipment and Operations, Second Edition, November 2001 (March 1, 2007). Global StandardsWellhead
All permanent equipment between the uppermost portion of the surface casing and the tubing-head adapter connection. Source: API SPEC 6A, Specification for Wellhead and Christmas Tree Equipment, Twentieth Edition, October 2010 (Addendum November 2012). Global StandardsWellhead Connector
Definition(s)
Wellhead Connector (Stack Connector)
See hydraulic connector.
Source: API Specification 16Q, Design, Selection, Operation, and Maintenance of Marine Drilling Riser Systems, Second Edition, April 2017. Global Standards