S

Definition(s)

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Static Gel Strength (SGS)

The yield stress of fluids at rest. Source: API STD 65 – Part 2, Isolating Potential Flow Zones During Well Construction, Upstream Segment, Second Edition, December 2010. Global Standards  

Static Gel Strength (SGS)

Shear strength (stress) measurement derived from force required to initiate flow of a fluid. Source: API RP 10B-6, Recommended Practice on Determining the Static Gel Strength of Cement Formulations, Upstream Segment, First Edition, August 2010. Global Standards  

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SPE

Society of Petroleum Engineers. Source: API STD 65 – Part 2, Isolating Potential Flow Zones During Well Construction, Upstream Segment, Second Edition, December 2010. Global Standards  

Definition(s)

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SGS

Static gel strength. Source: API STD 65 – Part 2, Isolating Potential Flow Zones During Well Construction, Upstream Segment, Second Edition, December 2010. Global Standards

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SCP

Pressure in an annulus that

1. rebuilds after having been bled down;
2. is not caused solely by temperature fluctuations; and
3. is not a pressure that has been imposed by the well operator

• Note: 1 to entry: Sustained casing pressure can be present on wells without annular access.

[SOURCE: API RP 90, modified] Source: ISO 16530-1:2017, Petroleum and natural gas industries — Well integrity – Part 1: Life cycle governance, First Edition, March 2017. Global Standards

SCP

Sustained Casing Pressure. 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 STD 65 – Part 2, Isolating Potential Flow Zones During Well Construction, Upstream Segment, Second Edition, December 2010. Global Standards  Source: 117 OLF, Norwegian Oil and Gas Association recommended guidelines for Well Integrity, No. 117, Revision No. 4, June 2011. Global Standards  

Sustained casing pressure (SCP)

Sustained casing pressure (SCP) is defined as pressure in any well annulus that is measurable at the wellhead and rebuilds when bled down, not caused solely by temperature fluctuations or imposed by the operator. Source: 117 OLF, Norwegian Oil and Gas Association recommended guidelines for Well Integrity, No. 117, Revision No. 4, June 2011. Global Standards

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Special Process

Operation that can change or affect the mechanical properties, including toughness, of the materials used in equipment. Source: API RP 8B, Recommended Practice for Procedures for Inspections, Maintenance, Repair and Remanufacture of Hoisting Equipment, Seventh Edition, March 2002 (Reaffirmed: August 2012). Global Standards  

Special Process

Operation that may change or affect the mechanical properties, including toughness, of the materials used in the equipment. Source: API SPEC 7K, Drilling and Well Servicing Equipment Upstream Segment, Fifth Edition, June 2010 (August 2010). Global Standards Source:API SPECIFICATION 7K, Drilling and Well Servicing Equipment, Sixth Edition, December 2015. Global Standards  

Special Process

An operation that can change or affect the mechanical properties, including toughness, of the materials used in the equipment. Source: API SPEC 8C, Drilling and Production Hoisting Equipment (PSL 1 and PSL 2), Fifth Edition, April 2012. Global Standards  

Special Process

Operation which converts or affects material properties. Source: API SPEC 16A, Specification for Drill-through Equipment, Third Edition, June 2004 (Errata/Supplement November 2004). Global Standards  

Special Process

A process where some aspects of the required quality cannot be assured by subsequent inspection of the processed material alone. Manufacturing special processes include welding, forming and the application of protective treatments. Inspection and testing processes classified as special processes include non-destructive examination and pressure and leak testing. Source: Rules and Regulations for the Classification of Mobile Offshore Units, Part 4, Steel Unit Structures, June 2013, Lloyd’s Register, Global Standards

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Serviceability

Condition of a piece of equipment at any point in time that affects the ability of the equipment to perform its function(s) as intended. Source: API RP 8B, Recommended Practice for Procedures for Inspections, Maintenance, Repair and Remanufacture of Hoisting Equipment, Seventh Edition, March 2002 (Reaffirmed: August 2012). Global Standards  

Serviceability

Ability of a structure or structural component to perform adequately for normal functional use. 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

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SWBM

Synthetic water-based mud. Source: API RP 7G-2, Recommended Practice for Inspection and Classification of Used Drill Stem Elements, First Edition, August 2009. Global Standards

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SOBM

Synthetic oil-based mud. Source: API RP 7G-2, Recommended Practice for Inspection and Classification of Used Drill Stem Elements, First Edition, August 2009. Global Standards

Definition(s)

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S/N

Signal-to-noise ratio. Source: API RP 7G-2, Recommended Practice for Inspection and Classification of Used Drill Stem Elements, First Edition, August 2009. Global Standards

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Sub

Short, threaded piece of pipe used to connect parts for the drilling assembly for various reasons, such as crossing over to a different connection, or to save wear and tear on more expensive elements. Source: API RP 7G-2, Recommended Practice for Inspection and Classification of Used Drill Stem Elements, First Edition, August 2009. Global Standards

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Straight Sub

Sub with no outside diameter change. Source: API RP 7G-2, Recommended Practice for Inspection and Classification of Used Drill Stem Elements, First Edition, August 2009. Global Standards

Definition(s)

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Stabilizer

Member of the drill stem assembly used to centralize or control the direction of the bottom-hole assembly. Source: API RP 7G-2, Recommended Practice for Inspection and Classification of Used Drill Stem Elements, First Edition, August 2009. Global Standards

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Stress-Relief Feature

A modification performed on rotary shouldered connections which removes the unengaged threads of the pin or box. This process makes the joint more flexible and reduces the likelihood of fatigue cracking in this highly stressed area. Source: API RP 7G, Recommended Practice for Drill Stem Design and Operating Limits, Upstream Segment, Sixteenth Edition, August 1998 (Addendum 2: September 2009). Global Standards

Definition(s)

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Slip Area

The slip area is contained within a distance of 48 inches along the pipe body from the juncture of the tool joint OD and the elevator shoulder. Source: API RP 7G, Recommended Practice for Drill Stem Design and Operating Limits, Upstream Segment, Sixteenth Edition, August 1998 (Addendum 2: September 2009). Global Standards  

Slip Area

That part of the pipe body where there is visible evidence of the trip slips having been repeatedly set numerous times in the same area. See Figure 4. NOTE At the upper end, it is typically located approximately 560 mm (22 in) from the box-tool joint elevator shoulder, and extends from that point approximately 660 mm (26 in) toward the pin end. It can be located elsewhere depending on rig design and positioning of handling equipment. It does not include occasional setting of slips in other areas as a result of fishing operations, drill stem tests and similar applications. Source: API RP 7G-2, Recommended Practice for Inspection and Classification of Used Drill Stem Elements, First Edition, August 2009. Global Standards

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Shear Strength

The stress required to produce fracture in the plane of cross section, the conditions of loading being such that the directions of force and of resistance are parallel and opposite although their paths are offset a specified minimum amount. The maximum load divided by the original cross-sectional area of a section separated by shear. Source: API RP 7G, Recommended Practice for Drill Stem Design and Operating Limits, Upstream Segment, Sixteenth Edition, August 1998 (Addendum 2: September 2009). Global Standards

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Std

Standard. Source: API RP 5C5, Recommended Practice on Procedures for Testing Casing and Tubing Connections, Third Edition, July 2003 (Reaffirmed August 2010). Global Standards Source: API RP 14G, Recommended Practice for Fire Prevention and Control on Fixed Open-type Offshore Production Platforms: Upstream Segment, Fourth Edition, April 2007. Global Standards  

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SRG

Seal ring groove. Source: API RP 5C5, Recommended Practice on Procedures for Testing Casing and Tubing Connections, Third Edition, July 2003 (Reaffirmed August 2010). Global Standards  

SRG

Stress-relief groove. Source: API RP 7G-2, Recommended Practice for Inspection and Classification of Used Drill Stem Elements, First Edition, August 2009. Global Standards  

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Specimen

Connection between two pieces of pipe. NOTE The specimen can be composed of one coupling and two pins for coupled connections, or one pin and one box for integral connections. Source: API RP 5C5, Recommended Practice on Procedures for Testing Casing and Tubing Connections, Third Edition, July 2003 (Reaffirmed August 2010). Global Standards

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Single Seal

One barrier or multiple barriers that cannot be physically differentiated in their function. Source: API RP 5C5, Recommended Practice on Procedures for Testing Casing and Tubing Connections, Third Edition, July 2003 (Reaffirmed August 2010). Global Standards

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Seal Ovality

Maximum seal diameter minus the minimum seal diameter divided by the average seal diameter multiplied by 100. NOTE Seal ovality is expressed as a percentage. Source: API RP 5C5, Recommended Practice on Procedures for Testing Casing and Tubing Connections, Third Edition, July 2003 (Reaffirmed August 2010). Global Standards

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Severe Galling

Galling that cannot be repaired by the use of fine files and abrasive paper. Source: API RP 5C5, Recommended Practice on Procedures for Testing Casing and Tubing Connections, Third Edition, July 2003 (Reaffirmed August 2010). Global Standards

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Safety Instrumented System

System composed of sensors, logic solvers, and final control elements for the purpose of taking the process to a safe state when predetermined conditions are met.

• NOTE Other terms commonly used for a SIS include emergency shutdown system (ESD, ESS), safety shutdown system (SSD), and safety interlock system (see E.3.3.1).

Source: API STD 521, Pressure-relieving and Depressuring Systems, Sixth Edition, January 2014. Global Standards

Safety Instrumented System

ISA S84.01 defines a safety instrumented system as a “system composed of sensors, logic solvers, and final control elements for the purpose of taking the process to a safe state when predetermined conditions are violated. Other terms commonly used include emergency shutdown system (ESD, ESS), safety shutdown system (SSD), and safety interlock system.” HIPS also fit the definition of a safety instrumented system. Source: API STD 521, Pressure-relieving and Depressuring Systems, Fifth Edition, January 2007 (Addendum May 2008). Global Standards  

Safety Instrumented System

System used to implement one or more safety-instrumented functions [2].

• Note: A safety-instrumented system is composed of any combination of sensor(s), logic solver(s), and actuator(s).

Source: ANSI/ISA–99.00.01–2007, Security for Industrial Automation and Control Systems, Part 1: Terminology, Concepts, and Models, 29 October 2007. National Standard

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Superimposed Back Pressure

Static pressure that exists at the outlet of a pressure-relief device at the time the device is required to operate. NOTE It is the result of pressure in the discharge system coming from other sources and can be constant or variable. Source: API STD 521, Pressure-relieving and Depressuring Systems, Fifth Edition, January 2007 (Addendum May 2008). Global Standards  

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Storage Tank or Storage Vessel

Fixed tank or vessel that is not part of the processing unit in petrochemical facilities, refineries, gas plants, oil and gas production facilities, and other facilities. cf. process tank (3.57). NOTE These tanks or vessels are often located in tank farms. Source: API STD 521, Pressure-relieving and Depressuring Systems, Fifth Edition, January 2007 (Addendum May 2008). Global Standards  

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Stoichiometric Air

Chemically correct ratio of fuel to air capable of perfect combustion with no unused fuel or air. Source: API STD 521, Pressure-relieving and Depressuring Systems, Fifth Edition, January 2007 (Addendum May 2008). Global Standards  

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Staged Flare

Group of two or more flares or burners that are controlled so that the number of flares or burners in operation is proportional to the relief gas flow. Source: API STD 521, Pressure-relieving and Depressuring Systems, Sixth Edition, January 2014. Global Standards Source: API STD 521, Pressure-relieving and Depressuring Systems, Fifth Edition, January 2007 (Addendum May 2008). Global Standards

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Shear Pin Device

Non-reclosing pressure-relief device actuated by static differential or static inlet pressure and designed to function by the shearing of a load-carrying member that supports a pressure-containing member. Source: API STD 521, Pressure-relieving and Depressuring Systems, Fifth Edition, January 2007 (Addendum May 2008). Global Standards  

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Safety Relief Valve

Spring-loaded pressure-relief valve that can be used as either a safety valve or a relief valve depending on the application. Source: API STD 521, Pressure-relieving and Depressuring Systems, Sixth Edition, January 2014. Global Standards Source: API STD 521, Pressure-relieving and Depressuring Systems, Fifth Edition, January 2007 (Addendum May 2008). Global Standards 

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Safety Integrity Level

Discrete integrity level of a safety instrumented function in a safety instrumented system.

• NOTE: SILs are categorized in terms of probability of failure; see Annex E.

Source: API STD 521, Pressure-relieving and Depressuring Systems, Sixth Edition, January 2014. Global Standards

Safety-Integrity Level (SIL)

Discrete integrity level of a safety instrumented function in a safety instrumented system. NOTE SILs are categorized in terms of probability of failure; see Annex E. Source: API STD 521, Pressure-relieving and Depressuring Systems, Fifth Edition, January 2007 (Addendum May 2008). Global Standards  

Safety-Integrity Level (SIL)

discrete level (one out of four) for specifying the safety integrity requirements of the safety instrumented functions to be allocated to the safety instrumented systems Note 1 to entry: Safety integrity level 4 is related to the highest level of safety integrity; safety integrity level 1 has the lowest. Note 2 to entry: The safety integrity level is a requirement about a safety instrumented function. The higher the safety integrity level, the higher the probability that the required safety instrumented function (SIF) will be carried out upon a real demand. Note 3 to entry: This term differs from the definition in IEC 61508–4[2] t o r eflect d ifferences i n p rocess sector terminology. Source: ISO/TR 12489:2013(E), Global Standards

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Subsurface Discontinuity (or Imperfection)

Any discontinuity that does not open to the surface (either ID or OD). Source: API RP 5A5, Field Inspection of New Casing, Tubing, and Plain-end Drill Pipe, Reaffirmed August 2010. Global Standards