Introduction of API 6D Ball Valve
Introduction of API 6D Ball Valve
In this article, you will learn about the different applications of high pressure ball valve API 6D.
Design pressure from 20 bar (g) to 1035 bar (g), in combination with other service conditions in hydrocarbon processes, refining, petro-chemistry, determinates ball valve construction, and material selection.
The construction of the valve type includes:
Cryogenic Ball Valve, LNG Ball Valve, Refining Ball Valve, Liquid Nitrogen Ball Valve, also include Control Ball Valve with Actuator motor.
This application can exist in combination with other service conditions, including corrosive & dirty applications with toxic substances, flammable liquids (LNG, LPG, or NGL condensate), or generic hydrocarbon gas in high pressure or high temperature applications.
Specific for API 607 Fire Safe, and API 6D qualified.
Low Pressure Ball Valves applied from PN20 (ANSI 150) to PN50 (ANSI 300)
Ball valves with low pressure range are suitable for topside or subsea installations with a wide range of available constructions and materials: carbon steel, stainless steel or other low alloys without any particular requirement regarding strength and resilient properties; no specific care is required to select thermoplastic inserts and elastomer seals unless specified by the customer or when combined with other service conditions. Like cryogenic ball valve, gas ball valve, trunnion ball valve, floating ball valve, electric motorized ball valve, and pneumatic actuator ball valve.
Soft seated ball valves can be supplied with a thermoplastic seat insert: PTFE, RPTFE, Nylon, Devlon V and PEEK, PCTFE; elastomer seat inserts are also available upon request.
PTFE and RPTFE are mostly popular for floating ball valves, trunnion ball valves, and PCTFE for cryogenic ball valve service.
Seals are mostly made by O-ring elastomers in FKM, HNBR, EPDM, FFKM, and FEPM, without the request of AED (Anti-explosion design) general, and lip seal is available for cryogenic ball valve.
Low pressure ball valves can be manufactured according to API 6D, API 6DSS, ASME B16.34, ASME B31.3, ASME B31.4, ASME B31.8, section V, Section VIII Div. 1 and 2 Section IX, ISO 14313, ISO 17292, EN 1092-1 or equivalent standards.
The low pressure application normally used for manual operator
a)Lever operator
Lever operation ball valve less than NPS 6, like floating ball valve, and trunnion ball valve.
Also small size cryogenic ball valve with lip seal.
b)Gear operator
Gear operation ball valve no less than NP 2, with a big torque force.
Like high temperature ball valve with the extended bonnet, Cryogenic ball valve with bigger size with high torque. And also severe service ball valve.
Middle Pressure Ball Valves applied PN100 (ANSI 600)
Ball valves with middle pressure range are suitable for topside or subsea installations with a large range of available constructions with few requirements regarding material selection: carbon steel, stainless steel or other low alloys can still be used, however, it is recommended a careful selection for stem materials which should be limited to good strength and resilient materials for gear operated or actuated ball valves unless specified by the customer or when combined with other service conditions. Like ESDV, SDV with actuator and general manual operator specific include cryogenic ball valve no less than NPS 2, floating ball valve and trunnion ball valve, also high temperature ball valve with extended bonnet.
Soft seated ball valves can be supplied with a thermoplastic seat insert: PTFE, RPTFE, Nylon, Devlon V and PEEK, PCTFE; elastomer seat inserts are also available upon request.
NYLON and PEEK become popular for middle pressure ball valves, cause of the material strength performance for different applications.
Seals are mostly made by O-ring elastomers, FKM ED, HNBR ED, FFKM and FEPM, with explosive decompression resistance in high pressure gas services, while it is not strictly required if liquids are present.
With the request of AED (Anti-explosion design) for elastic molecular safety, PTFE lip seals can be used. Medium pressure ball valves cryogenic ball valve service, floating ball valve, and trunnion ball valve, all can be manufactured according to API 6D, API 6DSS, ASME B16.34, ASME B31.3, ASME B31.4, ASME B31.8, section V, Section VIII Div. 1 and 2 Section IX, ISO 14313, ISO 17292, EN 1092-1 or equivalent standards.
The middle pressure ball valves widely used for ESDV, SDV
a)ESDV Ball Valve:
Used for emergency shut down less than 3 seconds with the pneumatic actuator to keep the pipeline safe.
Can be used for Cryogenic Ball Valve, Severe Service Ball Valve, High Temperature Ball Valve
b)SDV Ball Valve:
Used for Shut down service with general cycle stroke time base on the model and site supply on the actuator.
The recommended design includes Cryogenic Ball Valve with pneumatic actuator, LNG ball valve with electric actuator, liquid nitrogen ball valve with the manual operator, and motorized ball valve.
High Pressure Ball Valves applied from PN150 (ANSI 900) to PN420 (ANSI 2500)
Ball valves with high pressure range are suitable for topside or subsea installations with a restricted range of available constructions and materials. A careful selection is required in this case: carbon steel, stainless steel, or other low alloys can be used, however duplex or high strength materials with good or excellent resilient properties should be used for ball, seat rings, and stem, both for manual or actuated ball valves, in order to withstand pressure ratings and actuators maximum allowable stem torque (MAST), unless specified by the customer or when combined with other service conditions.
Soft seated ball valves can be supplied with a thermoplastic seat insert with good wear resistance and low friction coefficient: Nylon, Devlon V, and PEEK should be selected, PEEK has widely used for long range temperature applications on -100℃~+250℃.
We selected PEEK for mostly high pressure ball valve, also floating ball valve and trunnion ball valve. Cryogenic ball valve didn’t in this range, cause the pressure is so high.
The elastomer seat inserts are also available upon request. Seals are mostly made by O-ring elastomers, FKM ED, HNBR ED and FFKM, anti-explosive decompression requirement is mandatory. Alternatively, PTFE lip seals can be used. High pressure ball valves can be manufactured according to API 6D, API 6DSS, ASME B16.34, ASME B31.3, ASME B31.4, ASME B31.8, section V, Section VIII Div. 1 and 2 Section IX, ISO 14313, ISO 17292, EN 1092-1 or equivalent standards.
Very High Pressure Ball Valves applied from PN720 (ANSI 4500) to PN1035 (API 15000)
Ball valves with this extreme design pressure range, are suitable for topside or subsea installations with a restricted range of available constructions and materials. A careful selection is required in this case: duplex or high strength materials with excellent resilient properties should be used. Soft seated ball valves can be supplied with a thermoplastic seat insert with excellent wear resistance and low friction coefficient: Devlon V and PEEK should be selected;
The elastomer seat inserts are also available upon request. Seals are mostly made by O-ring elastomers, FKM ED, and HNBR ED, anti-explosive decompression requirement is mandatory. Alternatively, PTFE lip seals can be used unless specified by the customer or when combined with other service conditions. Very high pressure all valves can be manufactured according to ASME B16.34, ISO 17292, API 6A, API 17D, ISO 14723, or equivalent standards.
