|DESIGN STANDARD||API 608 / API 6D / BS 5351 / CSA Z245.15|
|SIZE RANGE||2” – 60”|
|FLOW BORE||Full Bore / Reduce Bore|
|BODY STYLE||2-piece / 3-piece / Welded Body / Top Entry|
|PRESSURE RATING||Class 150 – 2500|
|WORKING TEMPERATURE||-45˚C ~ +220˚C (higher temperature & cryogenic applications available on request)|
|END CONNECTION||ASME B16.5 - Flange (RF, RTJ) ASME B16.25 – Butt-Weld|
|FACE to FACE||ASME B16.10|
|FIRE SAFE||API 607 / API 6FA|
|TEST & INSPECTION||API 598 / BS 6755 / API 6D|
Two floating seat retainers are used for the seat sealing. They float axially to seal against the ball. High-pressure sealing is realized by a pressure-assisted mechanism, while a pre-loaded spring ensures tight sealing under very low differential pressure in both soft and metal seated configuration.
The seat insert for soft-seated configuration is made of thermoplastic material with multiple options depending on the actual operating conditions.
VAHN-TECH (vt) Ball Valves are designed and manufactured to meet the requirements of API 607 & API 6FA and to prevent both internal and external leakage in the event of a fire.
Internal Leak Prevention: In case of a fire destroying the thermoplastic sealing, the ball will seal against the metal face of the seat retainer, providing a secondary metal-to-metal seal, preventing leak through the burnt seat. The flexible graphite seat retainer seal prevents leakage past the seat retainer.
External Leak Prevention: Secondary seals, including packing and O-rings, in the stem area or valve body joints are coupled with flexible graphite packing rings. The high temperature resistance of the graphite material will prevent external leakage in case of fire.
The one-piece stem design includes a step preventing blow out, even during maintenance operation or incidental cavity pressure rise.
During on-off operations, friction between the ball and the non-metal seat can produce an electrostatic charge that can accumulate on the ball surface. Antistatic devices (ball loaded spring/springs) are assembled between stem and ball to permit electric conductivity through all metallic components to prevent static sparks.
Trunnion Mounted Ball Valves are used mainly in the following industries:
The sulphur-resisting series are used mainly for highly corrosive natural gas pipelines containing hydrogen sulphide impurities.
VAHN-TECH (vt) can provide any size of ball valves with an extended bonnet for special installation requirements, such as buried service and low temperature and cryogenic applications.
VAHN-TECH (vt) cryogenic ball valves are suitable for LNG storage, tank applications, cryogenic pumps, pipelines or low-pressure trailers. The valves provide high flow capacity, tight shutoff, and long service-free life in extreme environmental conditions. Cryogenic ball valves are available in all sizes and pressure classes for operating temperatures from -196°C to +120°C.
VAHN-TECH (vt) provides metal seated ball valve design for high temperature and hot gas applications up to 550˚C /1022˚F. Special trims are selected to provide optimized resistance and sealing in an aggressive environment.
Tungsten Carbide/Chrome Carbide and Hard Graphite seated options are available. All gaskets and seals are metal and graphite-based types, which are suitable for high-temperature service. Precise machining and lapping of the ball and seat ensure best in class leakage tightness, solving inner leakage and outer leakage issues, including high pressure and abrasive media.