Stationkeeping System

Stationkeeping 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 Standards  

Stationkeeping 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 Standards  
Stress Amplification Factor

Stress 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 Standards

Stress 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 Standards  

Stress 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.
Source: API Technical Report 17TR7, Verification and Validation of Subsea Connectors, First Edition, April 2017. Global Standards  

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 Standards  

Stress 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.
Source: ISO 13624-1:2009, Petroleum and natural gas industries – Drilling and production equipment – Part 1:Design and operation of marine drilling riser equipment. Global Standards
Shallow Intermediate Liner

Shallow Intermediate Liner

Definition(s)

Shallow intermediate liner

Large diameter casing normally run as a liner and hung in a profile in the surface casing (18 in. can be called “surface extension” by regulators). Normal clearance casing OD in.: N/A. Tight clearance casing OD in.: 18 and/or 16. NOTE These are examples only. Each well can have variations in number of casing strings and sizes. Naming conventions can vary. The heavy-wall surface casing designs may allow 13 5/8 in. to be run as a liner and not tied back. Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global Standards  
SWF

SWF

Definition(s)

SWF

Shallow water flow. Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global Standards Source: API RP 65, Cementing Shallow Water Flow Zones in Deepwater Wells, First Edition, September 2002 (August 2003). Global Standards Source: Deepwater Well Control Guidelines. IADC Guidelines
SWA

SWA

Definition(s)

SWA

Stop work authority. Source: API  Bulletin 97, Well Construction Interface Document Guidelines, First Edition, December 2013. Global Standards Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global Standards  
SSTT

SSTT

Definition(s)

SSTT

Subsea test tree. Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global Standards  
SRB

SRB

Definition(s)

SRB

Sulfate reducing bacteria. Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global Standards  

SRB

Sulphate reducing bacteria. Source: Offshore Standard DNV-OS-C101, Design of Offshore Steel Structures, General (LRFD Method, Det Norske Veritas, April 2011. Global Standards  
System Reliability

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 Standards  
Swab

Swab

Definition(s)

Swab

The lowering of the hydrostatic pressure in the well bore due to upward movement of tubulars and/or tools. Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global Standards  
Surge

Surge

Definition(s)

Surge

An increase in downhole pressure that occurs when a string is lowered in the well or when circulation is initiated. Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global Standards  

Surge

Vessel motion along the for/aft axis. 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 Standards  

Surge

Vessel motion along the fore/aft axis. Source: API RP 17G, Recommended Practice for Completion/Workover Risers, Second Edition, July 2006 (Reaffirmed April 2011). Global Standards Source: ISO 13624-1:2009, Petroleum and natural gas industries – Drilling and production equipment – Part 1:Design and operation of marine drilling riser equipment. Global Standards  

Surge

  1. pressure change produced by conditions such as pump or compressor startup or shutdown, valve openings or closures, and line leaks.
  2. pulsating flow in centrifugal compressors caused by operating under low flow conditions.
Source: IADC UBO / MPD Glossary, December 2011. Global Standards
Surface Cement Plug

Surface Cement Plug

Definition(s)

Surface cement plug

The shallowest cement plug set below the mudline for well abandonments. Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global Standards  
Subsea Tree

Subsea Tree

Definition(s)

Subsea Tree

A system of valves placed on the subsea wellhead designed to control the flow into or out of the completed well. NOTE The subsea tree may provide numerous additional functions [e.g. chemical injection points, well intervention means, pressure relief means (annulus vent), etc.]. Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global Standards  

Subsea Tree

Assembly of valves attached to the uppermost connection of the subsea wellhead and used to control well production. Source: API Standard 2RD, Dynamic Risers for Floating Production Systems, Second Edition, September 2013. Global Standards Source: API RP 17G, Recommended Practice for Completion/Workover Risers, Second Edition, July 2006 (Reaffirmed April 2011). Global Standards  
String

String

Definition(s)

String

Assembly of individual tubular joints. EXAMPLES Casing, drill pipe, tubing, etc. Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global Standards  
Stop Work Authority

Stop Work Authority

Definition(s)

Stop work authority (SWA)

A program that provides all operator and contractor/service personnel, directly or indirectly involved with the operation, the responsibility and authority to cease work until a review of the activity can be concluded, and it has been found safe to resume such activity. Source: API  Bulletin 97, Well Construction Interface Document Guidelines, First Edition, December 2013. Global Standards

Stop work authority (SWA)

A process that provides all operator and contractor/service personnel, directly or indirectly involved with the operation, the responsibility and authority to cease work until a review of the activity can be concluded and it has been found safe to resume such activity. Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global Standards
Stationkeeping

Stationkeeping

Definition(s)

Stationkeeping

Maintenance of a vessel’s desired operating position or station (within stated tolerances) relative to the wellhead or to another vessel. Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global Standards  
Standard Operating Procedure

Standard Operating Procedure

Definition(s)

Standard operating procedure (SOP)

A detailed written procedure used to safely execute a recurring work process in a consistent manner. Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global Standards  
Stakeholder

Stakeholder

Definition(s)

Stakeholder

A person or organization that is affected or can be affected by an organization's actions and policies. Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global Standards  

Stakeholder

An individual or organization having a right, share, claim or interest in a system. Source: IMO MSC.1/Circ.1512, Guideline on Software Quality Assurance and Human-Centred Design for e-navigation, 8 June 2015, International Maritime Organization. Regulatory Guidance  

Stakeholder

Person or organization that can affect, be affected by, or perceive themselves to be affected by a decision or activity. NOTE A decision maker can be a stakeholder. Source: ISO Guide 73:2009(E/F), Risk Management – Vocabulary, First Edition, 2009. Global Standards  

Stakeholder

<risk management> person or organization that can affect, be affected by, or perceive themselves to be affected by a decision or activity. [ISO Guide 73:2009] Source: ISO/IEC 27032:2015, Information technology — Security techniques — Guidelines for cybersecurity, First Edition, July 2012. Global Standards  

Stakeholder

<system> individual or organization having a right, share, claim or interest in a system or in its possession of characteristics that meet their needs and expectations [ISO/IEC 12207:2008] Source: ISO/IEC 27032:2015, Information technology — Security techniques — Guidelines for cybersecurity, First Edition, July 2012. Global Standards  

Stakeholder

Person or organization that can affect, be affected by, or perceive themselves to be affected by a decision or activity. [SOURCE: ISO Guide 73:2009]. Source: ISO/IEC 27000:2014, Information technology — Security techniques — Information security management systems — Overview and vocabulary, Third Edition, January 2014. Global Standards
Shoe Track

Shoe Track

Definition(s)

Shoe track

The space inside the casing between the float/guide shoe and the landing/float collar. NOTE This space provides a volume that helps prevent over displacement of the primary cement job; thus, the shoe track is typically filled with cement or a cement-mud combination due to wiper plug mud film displacement. Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global Standards  
SEMS

SEMS

Definition(s)

SEMS

Safety and environmental management system. Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global Standards Source: API  Bulletin 97, Well Construction Interface Document Guidelines, First Edition, December 2013. Global Standards Source:API RP T-1, Creating Orientation Programs for Personnel Going Offshore, Fifth Edition, November 2016. Global Standards
Safety and Environmental Management System

Safety and Environmental Management System

Definition(s)

Safety and environmental management system (SEMS)

Structured set of interdependent doctrines, documents, and principles that are intended to ensure that the activities of an organization are directed, planned, and conducted safely. Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global Standards Source: API  Bulletin 97, Well Construction Interface Document Guidelines, First Edition, December 2013. Global Standards
Strength Retrogression

Strength Retrogression

Definition(s)

Strength Retrogression

Reduction in compressive strength and increase in permeability of a cement caused by exposure to temperatures exceeding 110 °C (230 °F). Source: API RP 10B-2, Recommended Practice for Testing Well Cements, First Edition, July 2005 (Reaffirmed: July 2010). Global Standards
Stirred Fluid-Loss Cell

Stirred Fluid-Loss Cell

Definition(s)

Stirred Fluid-Loss Cell

Cell specially designed to allow for conditioning of the cement slurry within the same cell used to perform a static fluid loss test. Source: API RP 10B-2, Recommended Practice for Testing Well Cements, First Edition, July 2005 (Reaffirmed: July 2010). Global Standards
Static Stability Test

Static Stability Test

Definition(s)

Static Stability Test

Test to determine the degree of sedimentation and free fluid development in a cement slurry. Source: API RP 10B-2, Recommended Practice for Testing Well Cements, First Edition, July 2005 (Reaffirmed: July 2010). Global Standards
Static Fluid Loss Test

Static Fluid Loss Test

Definition(s)

Static Fluid Loss Test

Test to determine fluid lost from a cement slurry when placed against a 325 mesh screen at 6 900 kPa (1 000 psi) differential pressure. Source: API RP 10B-2, Recommended Practice for Testing Well Cements, First Edition, July 2005 (Reaffirmed: July 2010). Global Standards
Starting Pressure

Starting Pressure

Definition(s)

Starting Pressure (pS)

Initial pressure applied to the test sample at the beginning of the thickening-time test. NOTE pS is also used to determine the pressure-up rate. Source: API RP 10B-2, Recommended Practice for Testing Well Cements, First Edition, July 2005 (Reaffirmed: July 2010). Global Standards
Sonic Strength

Sonic Strength

Definition(s)

Sonic Strength

Extent of strength development of a cement sample calculated by measuring the velocity of sound through it. NOTE The calculation is based on specific mathematical correlations and not on direct measurements of strength. Source: API RP 10B-2, Recommended Practice for Testing Well Cements, First Edition, July 2005 (Reaffirmed: July 2010). Global Standards
Slurry Container

Slurry Container

Definition(s)

Slurry Container

Container in a pressurized consistometer used to hold the slurry for conditioning purposes or for thickeningtime test. Source: API RP 10B-2, Recommended Practice for Testing Well Cements, First Edition, July 2005 (Reaffirmed: July 2010). Global Standards
Sedimentation

Sedimentation

Definition(s)

Sedimentation

Separation and settling of solids in a cement slurry. Source: API RP 10B-2, Recommended Practice for Testing Well Cements, First Edition, July 2005 (Reaffirmed: July 2010). Global Standards
Subsea Wells

Subsea Wells

Definition(s)

Subsea Wells

Wells drilled and completed with a subsea wellhead located near the seafloor. Source: API STD 65 – Part 2, Isolating Potential Flow Zones During Well Construction, Upstream Segment, Second Edition, December 2010. Global Standards  

Subsea Well

Wells completed with a subsea wellhead and a subsea tree. Source: ISO 16530-1:2017, Petroleum and natural gas industries — Well integrity – Part 1: Life cycle governance, First Edition, March 2017. Global Standards Source: API RP 90, Annular Casing Pressure Management for Offshore Wells, Upstream Segment. First Edition, August 2006. Global Standards
Structural Pipe (or casing)

Structural Pipe (or casing)

Definition(s)

Structural Pipe (or casing)

Pipe utilized to facilitate the drilling of a well, but not intended for pressure containment after the well has been drilled. Supports unconsolidated sediments and provides hole stability for initial drilling operations, axial support for casing loads and bending loads from the wellhead. See also definition for drive/jet pipe. Source: API STD 65 – Part 2, Isolating Potential Flow Zones During Well Construction, Upstream Segment, Second Edition, December 2010. Global Standards  

Structural

Large OD casing; jetted in or drilled and cemented. Normal clearance casing OD in.: 30. Tight clearance casing OD in.: 36. NOTE These are examples only. Each well can have variations in number of casing strings and sizes. Naming conventions can vary. The heavy-wall surface casing designs may allow 13 5/8 in. to be run as a liner and not tied back. Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global Standards