Glossary
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Systems Approach
Definition(s)
Systems approach
For this document, systems approach will be defined as the loads or combination of loads along the length of the well. Generally, these loads are the result of pressure, tension, bending, and compression loads (both dynamic and static) on the components that will be transferred from component to component as these components are connected in the well configuration. These loads generally are transferred to the earth at the shoe through a cemented shoe joint, along the cemented casing and at the wellhead. Source: API TR 1PER15K-1, Protocol for Verification and Validation of High-pressure High-temperature Equipment, First Edition, March 2013. Global StandardsValidation Process
Definition(s)
Validation process
The validation process is the methodology to incorporate the basis of design in system testing and validate the results of the verification process. Source: API TR 1PER15K-1, Protocol for Verification and Validation of High-pressure High-temperature Equipment, First Edition, March 2013. Global StandardsFailure Modes and Effects Analysis
Definition(s)
Failure Modes and Effects Analysis
Failure Modes and Effects Analysis (FMEA) means a systematic analysis of systems and sub-systems to a level of detail that identifies all potential failure modes down to the appropriate sub-system level and their consequences.
Source: IMO MSC.1/Circ.1580, GUIDELINES FOR VESSELS AND UNITS WITH DYNAMIC POSITIONING (DP) SYSTEMS, 16 June 2017, International Maritime Organization. Regulatory GuidanceFailure Modes and Effects Analysis
A systematic analysis of systems and sub-systems to a level of detail that identifies all potential failure modes down to the appropriate sub-system level and their consequences. Source: ISO 16530-1:2017, Petroleum and natural gas industries — Well integrity – Part 1: Life cycle governance, First Edition, March 2017. Global StandardsFailure Modes and Effects Analysis (FMEA)
FMEA is a methodology developed during the 1940s by the U.S. armed forces. It was later used in aerospace. It was applied to hazard analysis and critical control point during the race to the Moon. It was introduced to the automotive industry in the 1970s. The oil and gas sector started using FMEA in the late 1990s. The FMEA methodology is currently an accepted practice used by the many oil and gas companies and suppliers as part of their toolkit in various areas of operations and design. The FMEA is designed to identify failure modes and hazards affecting a focus item (focus items can be a component, a subsystem, or a system). The main goal is to come up with solutions to prevent the failure from happening, hence, improving the reliability of the focus item. It is preferably applied at as many levels as feasible of the system in question to include more specific solutions. The narrower the focus of the FMEA, the more specific the solution to the problem. FMEA has been used extensively in other industries, and it is becoming an integral part of the development process in the upstream oil and gas industry. The FMEA table follows the validation process discussed in the main document and presented in Figure C.1. Source: API TR 1PER15K-1, Protocol for Verification and Validation of High-pressure High-temperature Equipment, First Edition, March 2013. Global StandardsFailure Modes and Effects Analysis (FMEA)
A hazard identification technique in which known failure modes of components or features of a system are considered and undesired outcomes are noted. FMEA is related to Fault Tree and Event Tree Analyses. 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 GuidelinesFailure Modes and Effects Analysis (FMEA)
Failure Mode and Effect Analysis (FMEA) is a tabulation of each item of equipment, its failure modes, and the effects on a system of any such failure. The FMEA technique concentrates on the cause and effect of failure of individual components or systems. Source: Approved Code of Practice for Managing Hazards to Prevent Major Industrial Accidents, Health and Safety in Employment Act 1992, Department of Labour, New Zealand, July 1994. Regulatory GuidanceElastic-plastic Analysis
Definition(s)
Elastic-plastic analysis
An analysis considering both the applied loading and deformation characteristics of the component. Source: API TR 1PER15K-1, Protocol for Verification and Validation of High-pressure High-temperature Equipment, First Edition, March 2013. Global StandardsDesign Verification
Definition(s)
Design Verification
Process of examining the result of design and development output to determine conformity with specified requirements.- NOTE: 1 Design verification activities can include one or more of the following (not an all-inclusive list):
- confirming the accuracy of design results through the performance of alternative calculations,
- review of design output documents independent of activities of design and development,
- comparing new designs to similar proven designs.
- NOTE: 2 Design verification is addressed in both API Q2 and this document differently. For API Q2, “design and development verification” refers to the design of the service provided by the service provider. For this document, “design verification” occurring under product definition refers to the design of the managed product being controlled by the service provider.
Design Verification (verification analysis)
Process of examining the result of design and development output (both during and after the design and development phase) to determine conformity with specified requirements.- NOTE: Design verification activities can include one or more of the following (this is not an all-inclusive list):
- confirming the accuracy of design results through the performance of alternative calculations,
- review of design output documents independent of activities of design and development,
- comparing new designs to similar proven designs.
Design Verification
Process of examining the result of a given design or development activity to determine conformity with specified requirements.- NOTE: These activities are described in 6.4. [ISO/TS 29001].
Design Verification
Process of examining the result of a given design or development activity to determine conformity with specified requirements. (See 6.6.) Source:API SPECIFICATION 19TT, Specification for Downhole Well Test Tools and Related Equipment, First Edition, October 2016. Global StandardsDesign Verification
Process of examining the result of a given design or development activity to determine conformity with specified requirements [ISO/TS 29001:2003]. Source: API SPEC 14A, Specification for Subsurface Safety Valve Equipment, Eleventh Edition, October 2005 (Reaffirmed June 2012). Global Standards Source: ISO/TS 29001:2010(E).Global StandardsDesign Verification
Process of examining the result of a given design or development activity to determine conformity with specified requirements. Source: API SPEC 17L1, Specification for Flexible Pipe Ancillary Equipment, First Edition, March 2013. Global StandardsDesign Verification
Process of examining the result of a given design or development activity to determine conformity with specified requirements. Source: API SPEC Q1, Specification for Quality Programs for the Petroleum, Petrochemical and Natural Gas Industry, Upstream Segment, Eighth Edition, December 2007 (Addendum December 2010). Global StandardsDesign Verification
Process of examining the result of a given design or development activity to determine conformity with specified requirements (API Q1).- NOTE: Design verification activities include one or more of the following:
- confirming the accuracy of design results through the performance of alternative calculations,
- review of design output documents independent of design and development review,
- comparing new designs to similar proven designs.
Design Validation
Definition(s)
Design Validation (validation testing or qualification)
Process of proving a design by testing to demonstrate conformity of the product to design requirements.- NOTE: Design validation can include one or more of the following (this is not an all-inclusive list):
- prototype tests,
- functional and/or operational tests of production products,
- tests specified by industry standards and/or regulatory requirements,
d) field performance tests and reviews
Source: API Technical Report 17TR7, Verification and Validation of Subsea Connectors, First Edition, April 2017. Global StandardsDesign Validation
Process of proving a design by testing to demonstrate conformity of the product to design requirements. NOTE Design validation can include one or more of the following (this is not an all-inclusive list):- prototype tests,
- functional and/or operational tests of production products,
- tests specified by industry standards and/or regulatory requirements,
- field performance tests and reviews.
Design Validation
Process of examining the result of design and development output to determine conformity with specified requirements. NOTE Design verification activities can include one or more of the following (this is not an all-inclusive list):- confirming the accuracy of design results through the performance of alternative calculations,
- review of design output documents independent of activities of design and development,
- comparing new designs to similar proven designs.
Design Validation
Process of proving a design by testing to demonstrate conformity of the product to design requirements [ISO/TS 29001:2003]. Source: API SPEC 14A, Specification for Subsurface Safety Valve Equipment, Eleventh Edition, October 2005 (Reaffirmed June 2012). Global StandardsDesign Validation
Process of proving a design by testing to demonstrate conformity of the product to design requirements. NOTE Seven standard design validation grades (V6 to V0) are specified in 6.5. [ISO/TS 29001]. Source: API SPEC 11D1, Packers and Bridge Plugs, Upstream Segment, Second Edition, July 2009. Global StandardsDesign Validation
Process of proving a design by testing to demonstrate conformity of the product to design requirements. Source: API STANDARD 18LCM, Product Life Cycle Management System Requirements for the Petroleum and Natural Gas Industries, First Edition, April 2017. Global Standards Source: API SPEC Q1, Specification for Quality Programs for the Petroleum, Petrochemical and Natural Gas Industry, Upstream Segment, Eighth Edition, December 2007 (Addendum December 2010). Global Standards Source:API SPECIFICATION 19TT, Specification for Downhole Well Test Tools and Related Equipment, First Edition, October 2016. Global Standards Source:ISO/TS 29001:2010(E).Global StandardsDesign validation
Process of proving a design by testing to demonstrate conformity of the product to design requirements (API Q1). NOTE Design validation includes one or more of the following: a) prototype tests, b) functional and/or operational tests of production products, c) tests specified by industry standards and/or regulatory requirements, d) field performance tests and reviews. Source: API TR 1PER15K-1, Protocol for Verification and Validation of High-pressure High-temperature Equipment, First Edition, March 2013. Global StandardsDesign Margin
Definition(s)
Design margin
The ratio of the structural capacity of a system to the applied loads or design loads. Source: API TR 1PER15K-1, Protocol for Verification and Validation of High-pressure High-temperature Equipment, First Edition, March 2013. Global StandardsCritical Crack Depth
Definition(s)
Critical crack depth
Crack dimension at which unstable crack propagation is predicted to occur based on fracture mechanics calculations. NOTE 1 Crack depth for a given load at which the stress intensity factor equals the plane strain fracture toughness (KIC). NOTE 2 Crack depth is that depth at which the combination of load ratio and toughness ratio are at the limit on the failure assessment diagram. Source: API TR 1PER15K-1, Protocol for Verification and Validation of High-pressure High-temperature Equipment, First Edition, March 2013. Global StandardsUser/purchaser
Definition(s)
User or user/purchaser
The company, organization or entity that purchases, installs, and/or uses equipment. Source: API TR 1PER15K-1, Protocol for Verification and Validation of High-pressure High-temperature Equipment, First Edition, March 2013. Global StandardsCorrosion-resistant Alloy
Definition(s)
Corrosion-resistant alloys
Nonferrous-based alloys where any one or the sum of the specified amount of the elements titanium, nickel, cobalt, chromium, and molybdenum exceeds 50 % mass fraction- NOTE: This definition is different from that in ISO 15156 (NACE MR0175/ISO 15156; see Clause 2).
Corrosion-resistant alloys (CRAs)
Alloys that are intended to be resistant to general and localized corrosion in oilfield environments that are corrosive to carbon steels. NOTE This definition is in accordance with ISO 15156-1 and is intended to include materials such as stainless steels with minimum 11,5 % mass fraction Cr, and nickel, cobalt and titanium base alloys. Other ISO documents can have other definitions. Source: API RP 17A Addendum 1, Design and Operation of Subsea Production Systems—General Requirements and Recommendations, December 2010. Global StandardsCorrosion resistant alloy
Alloy intended to be resistant to general and localized corrosion by oilfield environments that are corrosive to carbon steels- NOTE: This definition is in accordance with ISO 15156-1 and is intended to include materials such as stainless steel with minimum 11,5 % (mass fraction) Cr, and nickel, cobalt and titanium base alloys. Other ISO standards can have other definitions.
Corrosion resistant alloy
Nonferrous-based alloy in which any one or the sum of the specified amount of the elements titanium, nickel, cobalt, chromium, and molybdenum exceeds 50 % (mass fraction) (API 6A). Source: API TR 1PER15K-1, Protocol for Verification and Validation of High-pressure High-temperature Equipment, First Edition, March 2013. Global StandardsBlowout Preventer Control System
Definition(s)
BOP control system
BOP functions are controlled using several methods such as direct, piloted, electro hydraulic, and MUX. One method employs piloted hydraulic controls. In this case, a hydraulic signal is transmitted from the surface control station to the subsea BOP. A hydraulic pilot valve receives the signal triggering the actuation of the subsea function. Because the hydraulic signal travels slowly, this type of control is best suited for use in shallower water depths. Another type of control uses electro-hydraulic technology. Systems in deeper water depths use multiplexed electrical or fiber optic signals sent from the surface to the pods to actuate the function on the subsea BOP. Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global StandardsVacuum Insulated Tubing
Definition(s)
Vacuum insulated tubing
VIT consists of a double tubing wall welded together on either the ID or OD of the joint. The vacuum between the two pipes achieves very low thermal conductivity to reduce heat transfer from the tubing to the surrounding annuli. Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global StandardsDynamic Positioning Systems (DPS)
Definition(s)
Dynamic Positioning System (DP system)
The complete installation necessary for dynamically positioning a vessel comprising, but not limited to, the following sub-systems:- power system
- thruster system
- DP control system
Dynamic Positioning System
Dynamic Positioning system (DP system) means the complete installation necessary for dynamically positioning a vessel comprising, but not limited to, the following sub-systems:- power system;
- thruster system; and
- DP control system
Dynamic Positioning Systems
Dynamic positioning systems are commonly used for stationkeeping on DW drilling rigs. These systems use information on the rig’s current location (e.g. as determined by a global positioning system and acoustic sensors) to control thrusters, which act to restore the rig to a position over the well’s center. Dynamically positioned drillships and semisubmersibles optimize stationkeeping by keeping the bow pointed in the direction of the metocean conditions. Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global StandardsDynamic Positioning System (DP System)
A system in which the power supply, thruster system and control system are incorporated together and can be operated such as to automatically maintain a fixed position. Source: Regulations relating to design and outfitting of facilities, etc. in the petroleum activities (the Facilities Regulations), Norway, April 2010 (amended December 2012). RegulationsMooring System
Definition(s)
Mooring system
Mooring systems are designed to keep rigs on location by exerting a restoring force on the rig when metocean conditions push the rig away from its station over the well. Anchors in the seabed are attached to the rig using large chains or lines. Mooring system configurations are often described based on the ratio of the water depth to anchor radius as follows: catenary mooring (typically 1:2 or greater); semitaut (typically 1:1.4); and taut (typically 1:1). The mooring system components vary depending on the system configuration. DW catenary and semitaut mooring systems are often comprised of steel wire and chain segments. Taut mooring systems will usually incorporate synthetic rope segments. Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global StandardsStationkeeping System
Definition(s)
Stationkeeping System
DW rigs maintain station (staying positioned over the wellhead location on the seafloor, within an operationally defined radius) by using either a mooring system or a dynamic positioning system. Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global StandardsStationkeeping System
System capable of limiting the excursions of a floating structure within prescribed limits. 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 StandardsWellhead Growth
Definition(s)
Wellhead growth
Wellhead growth is the term used for axial movement of the wellhead relative to its initial position at the mudline. Wellhead growth is caused by the forces exerted on the wellhead by: thermal expansion/contraction of tubulars tied back to the wellhead and subsidence, and increasing pressure within the annuli created between the tubulars. Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global StandardsPod
Definition(s)
POD
Point of disconnect. Source: API Specification 16Q, Design, Selection, Operation, and Maintenance of Marine Drilling Riser Systems, Second Edition, April 2017. Global StandardsPoD
Probability of detection. Source: API Technical Report 17TR7, Verification and Validation of Subsea Connectors, First Edition, April 2017. Global StandardsPod
The control system valve package. Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global StandardsPod
See control pod. 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 StandardsCasing Displacement
Definition(s)
Casing displacement
Displacement of fluid below the marine riser is known as a casing displacement. Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global StandardsRiser Failure Analysis
Definition(s)
Riser failure analysis
Also known as a weak point analysis. Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global StandardsStress Amplification Factor
Definition(s)
Stress amplification factor
Equal to the local peak alternating stress in a component (including welds) divided by the nominal alternating stress in the pipe wall at the location of the component.
Source: API Specification 16Q, Design, Selection, Operation, and Maintenance of Marine Drilling Riser Systems, Second Edition, April 2017. Global StandardsStress amplification factor
The ratio of the localized stress to the stress in adjacent material. Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global StandardsStress amplification factor
Equal to the local peak alternating stress in a component (including welds) divided by the nominal alternating stress in a defined reference section somewhere in the system (e.g. through wall section of the wellhead above or below the locking profile).- NOTE: This factor is used to account for the increase in the stresses caused by geometric stress amplifiers which occur in connector components.
Stress amplification factor (SAF)
Equal to the local peak alternating stress in a component (including welds) divided by the nominal alternating stress in the pipe wall at the location of the component. This factor is used to account for the increase in the stresses caused by geometric stress amplifiers which occur in riser components. 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 StandardsStress Amplification Factor
Value equal to the local peak alternating stress in a component (including welds) divided by the nominal alternating stress in the pipe wall at the location of the component.- NOTE: This factor is used to account for the increase in the stresses caused by geometric stress amplifiers that occur in riser components.