Glossary
Browse the IADC Lexicon alphabetically or by category. Get comprehensive definitions of drilling industry terms.
CIU
Definition(s)
CIU
Chemical injection unit. Source: API SPEC 17F, Specification for Subsea Production Control Systems, Second Edition, December 2006 (Reaffirmed April 2011). Global StandardsCISPR
Definition(s)
CISPR
Comité International Spécial des Perturations Radioelectrique (International Special Committee on Radio-Interference). Source: API SPEC 17F, Specification for Subsea Production Control Systems, Second Edition, December 2006 (Reaffirmed April 2011). Global StandardsCB
Definition(s)
CB
Centre of buoyancy. Source: API SPEC 17F, Specification for Subsea Production Control Systems, Second Edition, December 2006 (Reaffirmed April 2011). Global StandardsBER
Definition(s)
BER
Bit error rate. Source: API SPEC 17F, Specification for Subsea Production Control Systems, Second Edition, December 2006 (Reaffirmed April 2011). Global Standardsβ
Definition(s)
β
Filtration ratio. Source: API SPEC 17F, Specification for Subsea Production Control Systems, Second Edition, December 2006 (Reaffirmed April 2011). Global StandardsWell Data
Definition(s)
Well Data
Data provided from the downhole equipment for reservoir description, flow calculations and routine production monitoring. NOTE Typically, these include sensor readings and valve positions. Source: API SPEC 17F, Specification for Subsea Production Control Systems, Second Edition, December 2006 (Reaffirmed April 2011). Global StandardsUnderwater Safety Valve
Definition(s)
Underwater Safety Valve
Safety valve assembly that is declared to be the USV and which will automatically close upon loss of power to that actuator. Source: API SPEC 17F, Specification for Subsea Production Control Systems, Second Edition, December 2006 (Reaffirmed April 2011). Global StandardsSurface Safety Valve
Definition(s)
Surface Safety Valve
Safety device that is located in the production bore of the well tubing above the wellhead (platform well), or at the point of subsea well production embarkation onto a platform, and that will automatically close upon loss of hydraulic pressure. Source: API SPEC 17F, Specification for Subsea Production Control Systems, Second Edition, December 2006 (Reaffirmed April 2011). Global StandardsSubsea Production Control System
Definition(s)
Subsea Production Control System
Control system operating a subsea production system during production operations. Source: API SPEC 17F, Specification for Subsea Production Control Systems, Second Edition, December 2006 (Reaffirmed April 2011). Global StandardsSignal Time
Definition(s)
Signal Time
Period of time elapsed between the remote initiation of a control command and the initiation of a control function operation subsea (the commencement of the shift time). Source: API SPEC 17F, Specification for Subsea Production Control Systems, Second Edition, December 2006 (Reaffirmed April 2011). Global StandardsShift Time
Definition(s)
Shift Time
Period of time elapsed between the arrival of a control signal at the subsea location (the completion of the signal time) and the completion of the control function operation. NOTE Of primary interest is the time to fully stroke, on a subsea tree, a master or wing valve that has been designated as the underwater safety valve. Source: API SPEC 17F, Specification for Subsea Production Control Systems, Second Edition, December 2006 (Reaffirmed April 2011). Global StandardsIntelligent Well Control System
Definition(s)
Intelligent Well Control System
Control system used to operate an intelligent well. Source: API SPEC 17F, Specification for Subsea Production Control Systems, Second Edition, December 2006 (Reaffirmed April 2011). Global StandardsIntelligent Well
Definition(s)
Intelligent Well
Well that employs permanently installed downhole sensors and/or permanently installed downhole control devices that are operable from a surface facility. Source: API SPEC 17F, Specification for Subsea Production Control Systems, Second Edition, December 2006 (Reaffirmed April 2011). Global StandardsHydrostatic Test Pressure
Definition(s)
Hydrostatic Test Pressure
Maximum test pressure at a level greater than the design pressure (rated working pressure). Source: API SPEC 17F, Specification for Subsea Production Control Systems, Second Edition, December 2006 (Reaffirmed April 2011). Global StandardsExpert Operation
Definition(s)
Expert Operation
Operating the IWCS with other control commands or other methods than used for normal operation. NOTE Typically used by IWCS supplier or other skilled resource to read IWCS diagnostic data and make (engineering) adjustments to IWCS equipment. Source: API SPEC 17F, Specification for Subsea Production Control Systems, Second Edition, December 2006 (Reaffirmed April 2011). Global StandardsElectrohydraulic Control
Definition(s)
Electrohydraulic Control
Control method wherein communication signals are conducted to the subsea system and used to open or close electrically-controlled hydraulic control valves. NOTE Hydraulic fluid is locally sourced and acts on the associated subsea valve actuator. “Locally sourced” may mean locally stored pressurized fluid or fluid supplied by a hydraulic umbilical line. With electrohydraulic control systems, data telemetry (readback) is readily available at high speed. Multiplexing of the communication signals reduces the number of conductors in the umbilical. Source: API SPEC 17F, Specification for Subsea Production Control Systems, Second Edition, December 2006 (Reaffirmed April 2011). Global StandardsDirect Hydraulic Control
Definition(s)
Direct Hydraulic Control
Control method wherein hydraulic pressure is applied through an umbilical line to act directly on a subsea valve actuator. NOTE Upon venting of the pressure at the surface, the control fluid is returned through the umbilical to the surface due to the action of the restoring spring in the valve actuator. Subsea functions may be ganged together to reduce the number of umbilical lines. Source: API SPEC 17F, Specification for Subsea Production Control Systems, Second Edition, December 2006 (Reaffirmed April 2011). Global StandardsDiagnostic Data
Definition(s)
Diagnostic Data
Data provided to monitor the condition of the downhole equipment. NOTE Can include the ability to make (engineering) adjustments. Source: API SPEC 17F, Specification for Subsea Production Control Systems, Second Edition, December 2006 (Reaffirmed April 2011). Global StandardsControl Path
Definition(s)
Control Path
Total distance that a control signal (e.g. electrical, optical, hydraulic) travels from the topside control system to the subsea control module or valve actuator. Source: API SPEC 17F, Specification for Subsea Production Control Systems, Second Edition, December 2006 (Reaffirmed April 2011). Global StandardsCommanded Closure
Definition(s)
Commanded Closure
Closure of the underwater safety valve and possibly other valves depending on the control system design. NOTE Such commands can originate manually, automatically or as part of an ESD. Source: API SPEC 17F, Specification for Subsea Production Control Systems, Second Edition, December 2006 (Reaffirmed April 2011). Global StandardsBoost
Definition(s)
Boost
Pressure maintained on the spring-return side of a subsea actuator for the purposes of improving closing-time response. Source: API SPEC 17F, Specification for Subsea Production Control Systems, Second Edition, December 2006 (Reaffirmed April 2011). Global StandardsIrregular Wave
Definition(s)
Irregular Wave
“Irregular wave” refers to a stochastic wave generated from a given wave spectrum. Source: API SPEC 17E, Specification for Subsea Umbilicals, Upstream Segment, Fourth Edition, October 2010. Global StandardsRegular Wave
Definition(s)
Regular Wave
“Regular wave” refers to a deterministic, harmonic wave with a given period and amplitude. Source: API SPEC 17E, Specification for Subsea Umbilicals, Upstream Segment, Fourth Edition, October 2010. Global StandardsNew Technology
Definition(s)
New Technology
New technology is technology that is not proven. This implies that the application of proven technology in a new environment or an unproven technology in a known environment, are both new technology. The degree of new technology can be classified in categories to be used as input to risk assessments (see DNV RP-A203). Source: API SPEC 17E, Specification for Subsea Umbilicals, Upstream Segment, Fourth Edition, October 2010. Global StandardsNew Technology
New technology as mentioned in the first subsection, may be new products, analysis tools or known products used in a new way. Source: Guidelines Regarding the Facilities Regulations, Norway, updated December 2012. Regulatory GuidanceProven Technology
Definition(s)
Proven Technology
In the field, proven technology has a documented track record for a defined environment. Such documentation shall provide confidence in the technology from practical operations, with respect to the ability of the technology to meet the specified requirements (see DNV RP-A203). Source: API SPEC 17E, Specification for Subsea Umbilicals, Upstream Segment, Fourth Edition, October 2010. Global StandardsWT
Definition(s)
WT
Wall thickness (mathematical symbol: t). Source: API SPEC 17E, Specification for Subsea Umbilicals, Upstream Segment, Fourth Edition, October 2010. Global StandardsTVE
Definition(s)
TVE
True volumetric expansion. Source: API SPEC 17E, Specification for Subsea Umbilicals, Upstream Segment, Fourth Edition, October 2010. Global StandardsTDR
Definition(s)
TDR
Time-domain reflectometry. Source: API SPEC 17E, Specification for Subsea Umbilicals, Upstream Segment, Fourth Edition, October 2010. Global StandardsPMI
Definition(s)
PMI
Positive material identification.Source: API STANDARD 16AR, Standard for Repair and Remanufacture of Drill-through Equipment, First Edition, April 2017. Global Standards
Source: API 570, Piping Inspection Code: In-service Inspection, Rating, Repair, and Alteration of Piping Systems, Fourth Edition, February 2016, with Addendum May 2017. Global Standards
PMI
Any physical evaluation or test of a material to confirm that the material, which has been or will be placed into service, is consistent with the selected or specified alloy material designated by the owner/user.- NOTE: These evaluations or tests can provide qualitative or quantitative information that is sufficient to verify the nominal alloy composition (see API 578).