• Stainless Steel Valve Body Material:Precision cast ASTM A351 CF8/CF8M (304/316 stainless steel) or forged A182 F304/F316 is adopted, featuring stable austenitic microstructure and excellent low-temperature toughness. Charpy V‑notch impact energy reaches ≥27J at -196℃, eliminating the risk of brittle fracture under cryogenic service. Grade 316 contains molybdenum, providing superior resistance to chloride pitting and crevice corrosion.

• Three‑Piece Body Structure:The valve body consists of a central main body and two side bodies connected by bolts. Internal components such as ball, seats and stem can be replaced without removing the valve from the pipeline, greatly reducing downtime and maintenance costs for cryogenic systems. It is especially suitable for continuous production systems that cannot be shut down.

• 8‑Inch Large‑Bore Design:DN200 nominal bore satisfies high‑pressure export of LNG and transportation of large‑flow cryogenic media. Full bore design facilitates pigging operations, while reduced bore is optional for optimized cost efficiency.

• 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 natural gas export after LNG vaporization and cryogenic pump discharge.

• Floating Ball (≤4" / Low Differential Pressure):Compact structure and low cost. Medium pressure assists sealing under medium and low differential pressure, ensuring reliable sealing.

• Trunnion‑Mounted Ball (≥6" or High Differential Pressure):Ball is fixed by upper and lower trunnions, enabling precise positioning under high differential pressure to avoid uneven wear of sealing surfaces. Suitable for large‑bore and high‑pressure applications.

• Extended Cryogenic Bonnet:The bonnet is extended above the seat to keep the packing chamber away from -196℃ cryogenic medium. The temperature gradient ensures packing operates above 0℃ to prevent stem icing and operational seizure. Extended dimensions comply with BS 6364 / ISO 28921‑1.

• Optional Vacuum Insulation:Vacuum jacket or polyurethane foam insulation is available for the bonnet and valve body to reduce cold loss, prevent external surface frosting and personnel frostbite, and improve system energy efficiency.

8" 900LB 3piece Cryogenic Stainless Steel Ball Valve 3D Diagram

J-VALVESSPE can supply a range ofseat types and configurationsto meet specific process needs:

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

Seat Design	Single piston effect (SPE)	Double piston effect(DPE)-DIB 1	Combined DIB 2
Bi-directional sealing	Yes	Yes	Yes
Body-Cavity Self relieving	Yes	No	Yes
Double Barrier	No	Yes	Yes (preferred direction only)

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.