API SPEC 14A:2005 pdf download

API SPEC 14A:2005 pdf download.Specification for Subsurface Safety Valve Equipment.
3.26
sour service
exposure to oilfield environments that contain H2S and can cause cracking of materials by the mechanisms addressed in ISO 15156
NOTE Adapted from ISO 15156-1:2001.
3.27
special feature
specific component or sub-assembly that provides a functional capability that is not validated during the validation test conducted in accordance with 6.5
3.28
subsurface safety valve
sssv
device whose design function is to prevent uncontrolled well flow when closed
NOTE SSSVs can be installed and retrieved by wireline or pump-down methods (wireline-retrievable) or be an integral part of the tubing string (tubing-retrievable).
3.29
subsurface safety valve equipment SSSV equipment
subsurface safety valve, and all components that establish tolerances and/or clearances which can affect its performance or interchangeability
3.30
stress corrosion cracking
scc
cracking of metal involving anodic processes of localized corrosion and tensile stress (residual and/or applied) in the presence of water and H2S
NOTE Chlorides and/or oxidants and elevated temperature can increase the susceptibility of metals to this mechanism of attack.
[ISO 151 56-1]
3.31
stress cracking
stress corrosion cracking, or sulfide stress cracking, or both
NOTE Adapted from NACE MR0175: Jan 2003.
3.32
stress relief
controlled heating of material to a predetermined temperature for the purpose of reducing any residual stresses
3.33
sulfide stress cracking
ssc
cracking of metal involving corrosion and tensile stress (residual and/or applied) in the presence of water and
H2S
NOTE SSC is a form of hydrogen stress cracking (HSC) and involves embrittlement of the metal by atomic hydrogen that is produced by acid corrosion on the metal surface. Hydrogen uptake is promoted in the presence of sulfides. The atomic hydrogen can diffuse into the metal, reduce ductility and increase susceptibility to cracking. High strength metallic materials and hard weld zones are prone to SSC.
[ISO 151 56-1]
5.1 General
5.1.1 Functional requirements
The user/purchaser shall prepare a functional specification for ordering products which conform with this International Standard and specify the following requirements and operating conditions, as appropriate, and/or identify the supplier’s/manufacturer’s specific product. These requirements and operating conditions may be conveyed by means of a dimensional drawing, data sheet or other suitable documentation.
5.1.2 Classes of service
SSSV equipment manufactured in accordance with this International Standard shall conform to one or more of the following classes of service. The user/purchaser shall specify the class(s), as applicable.
Class 1: standard service. This class of SSSV equipment is intended for use in wells which are not expected to exhibit the detrimental effects defined by Classes 2, 3, or 4.
— Class 2: sandy service. This class of SSSV equipment is intended for use in wells where particulates such as sand could be expected to cause SSSV equipment failure.
Class 3: stress cracking service. This class of SSSV equipment is intended for use in wells where water containing corrosive agents can cause stress cracking. Class 3 equipment shall meet the requirements for Class I or Class 2 service and be manufactured from metallic materials that are demonstrated as resistant to sulfide stress cracking and stress corrosion cracking.
The supplier/manufacturer shall ensure that the metallic materials used in Class 3 equipment meet the metallurgical requirements of ISO 15156 (all parts) for sour service and/or shall be suitable for service in non-sour-containing environments where stress corrosion cracking can occur.
The user/purchaser shall ensure that the specific metallic materials contained within Class 3 equipment are suitable for the intended application.
Within Class 3, there are two sub-classes, as follows:
1) 3S for sulfide stress cracking service and stress corrosion cracking service in which chlorides are present in a sour environment. Metallic materials suitable for a 3S environment shall be in accordance with ISO 15156 (all parts).
2) 3C for stress corrosion cracking service in a non-sour environment. Metallic materials suitable for Class 3C non-sour service are dependent on specific well conditions; no national or international standards exist for the application of metallic materials for this class of service.
NOTE For the purposes of these provisions, NACE MROI 75/ISO 15156-1-2-3, is equivalent to ISO 15156 (all parts).
Class 4: mass loss corrosion service (see 3.16). This class of SSSV equipment is intended for use in wells where corrosive agents could be expected to cause mass loss corrosion. Class 4 equipment shall meet the requirements for Class 1 or Class 2 and be manufactured from materials which are resistant to mass loss corrosion. Metallic materials suitable for Class 4 service are dependent on specific well conditions; no national or international standards exist for the application of metallic materials for this class of service.