• Three-Piece Body Structure: The valve body consists of a main body and two side bodies connected by bolts for easy disassembly. Internal components can be replaced without removing the valve from the pipeline, significantly reducing downtime and maintenance costs for cryogenic systems.

• Cryogenic Trunnion-Mounted Design: The ball is secured in the body bearings by upper and lower trunnions, maintaining precise positioning under low-temperature shrinkage and high differential pressure conditions, eliminating the risk of seal failure common in floating ball valves, and ensuring long-term reliable sealing.

• 900LB High-Pressure Class: Class 900 (PN150) pressure rating with a maximum working pressure of 15.3 MPa at ambient temperature, meeting high-pressure service requirements such as high-pressure LNG export and cryogenic pump discharge.

• Extended Bonnet Design: The bonnet is extended above the seat to keep the packing gland area away from cryogenic media, preventing stem icing and operational seizure. The extended dimension complies with BS 6364, ensuring the packing operates within a suitable temperature range.

• Optional Vacuum Insulation Layer: Vacuum jacket or polyurethane foam insulation can be optionally fitted to the bonnet and body to reduce cold loss, prevent surface frosting and icing, and improve system energy efficiency and operational safety.

• Seat Sealing: PCTFE (Kel-F), modified PTFE, or metal seals are used to retain elasticity and sealing performance at low temperatures, avoiding cold flow and embrittlement.

• Stem Packing: Pure graphite, Inconel wire-reinforced graphite, or special low-temperature V-type PTFE combinations are applied to ensure reliable sealing and low-emission performance at -196℃.

• Gasket: Stainless steel graphite spiral wound gaskets or metal ring gaskets are used to compensate for low-temperature shrinkage and prevent flange leakage.

• Top-Entry Design: An access port is provided on the top of the valve body, allowing online replacement of the ball, seats, and stem without valve removal, especially suitable for welded cryogenic piping systems.

• Fire-Safe Design: Compliant with API 607 / ISO 10497 standards. In the event of fire damage to soft seals, metal seats contact the ball to form a metallic seal, preventing media leakage during fire incidents.

  
  

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.