• Stainless Steel Valve Body: Forged from high-quality stainless steel and nickel-base alloys including ASTM A182 F304/F316/F316L, F321/F347, F51/F53 duplex stainless steel, CK3MCuN (254SMO), Inconel 625/718, etc., featuring excellent high-temperature resistance, corrosion resistance and anti-creep properties.

• Trunnion Mounted Structure: The ball is secured by upper and lower trunnion shafts and does not float under medium pressure. Sealing is achieved via spring-loaded seats or piston effect, which significantly reduces operating torque, making it ideal for high-pressure and large-bore applications.

• Metal Hard Seal Design: Sealing surfaces of the seat and ball adopt SS316/SS316L with Stellite overlay, Inconel 625 with tungsten carbide, solid tungsten carbide or ceramic coating, with hardness ≥ HRC 40. It withstands high temperature, erosion and solid particle wear, achieving Class VI sealing or bubble-tight shutoff.

• Tri-Offset or Spherical Sealing Geometry: The sealing surfaces of the seat and ball are precisely matched with optimized contact angles, enabling low-torque operation and reliable sealing. The tri-offset design eliminates friction during opening and closing, extending service life.

• Full Bore or Reduced Bore Passage: Full bore design provides nearly zero flow resistance and allows pig passage. Reduced bore design lowers costs and is suitable for general shut-off service.

• Precision Grinding & Coating Technology: Ball roundness ≤ 0.005 mm, surface roughness Ra ≤ 0.2 μm. Combined with HVOF tungsten carbide spraying, plasma-sprayed ceramic coating or electroless nickel plating (ENP), it delivers high hardness, strong bonding strength and excellent wear resistance.

• Self-Relief & Emergency Sealing: Cavity pressure self-relief design (SPE) prevents overpressure in the body cavity. A sealant injection fitting is provided at the stem to restore sealing in emergency situations.

• Anti-Static & Fire-Safe Design: Conductive connections are established between the stem, ball and valve body. Certified to API 607/6FA fire-safe standards, metal seals maintain tightness after fire exposure to prevent medium leakage.

• High-Temperature Heat Dissipation & Extended Bonnet Neck: For high-temperature service (>200℃), the valve is equipped with a heat-dissipating bonnet neck and high-temperature packing (flexible graphite, ceramic fiber) to protect the actuator. For low-temperature service, an extended bonnet neck is used to prevent packing freezing.

J-VALVES trunnion mounted ball valves standard seat ringsare soft-seated by the use of athermoplastic or elastomeric or Meta

Seats-Tungsten /Chrome carbide /ENP

Single Piston (SPE) , Double Piston effect (DPE) and Combination (SPE x DPE) seats are available.

Seat Princlple

Two independent seat rings grant the sealing, barrieragainst the line pressure actingon the upstream and downstreamsides of the valve which allows the valve tobe bidirectional.

A set ofcoil springs acting, between the upstream side ofeach seatring,andthe body,generate an uniform thrust on theseat which push the same against the ball and grant the sealingfeature with no orverylow pressureinthe line,when the line pressure increasethe thrust actingon theseat increases proportionally and the sealing leatureis granted throughout the fullpressure range.

The J-VALVES SPE trunnion mounted ball valves are available with Double

Block & Bleed in dependent oftheseat type.

Valve seating variations

Single Piston Effect

Single piston effect (SPE) is the stand ard feature for theseat rings of the J-VALVES SPE trunnion mounted ball valves.

On a SPE seat ring:

The pressure ac tingon the upstream side ofthe seat ringgenerates aforce which push theseattowards the ball.The pressure actingon the downstream side ofthe seatring generates a force which pull theseatring away fromthe ball.

Anyoverpressure which may be generated by the thermal expansion of the fluid trapped in thebodycavity with the ballin fully closed position, will beautomatically dischargedinthe line on the lower pressure side.

Double Piston Effect

Double piston effect(DPE) is a stand ard feature fortheseat rings ofthe J-VALVES trunnion mounted ball valves & recommended forwelded body valves. Ona DPE seat ring, both the pressure acting on the upstream sideof theseatring andthe pressure acting on thedownstreamside of the  seatring, generatea forcewhich push the seattowards the ball.

With th is type ofseat ring,the eventual over press ure whichmay be generated by the thermal expansion ofthe fluidtrappedinthebodyeavitywith theball in fullyclosed position,can be discharged by the use of:

An external safetyrelief device.

The Double Piston Effect grants a double sealingfeature,iftheupstreamseat ringisdamaged, thedown stream seatgrant the sealingfeature of the valve.