Marine Grade Top Entry Ball Valve with Extended Stem

• Body: ASTM A216 WCB carbon steel (coated for corrosion protection), A351 CF8/CF8M stainless steel (seawater corrosion resistant), B148 C95800 aluminum bronze (resistance to biofouling)

• Ball/Stem: 316 stainless steel, Monel K500, 17-4PH, seawater corrosion resistant and torsion resistant

• Bolts and Nuts: B8M stainless steel with PTFE coating or hot-dip galvanized, anti-galling and resistant to galvanic corrosion

• Top Entry Design: Internals including ball, seats and stem can be disassembled and replaced from the top of the body without pipe cutting or valve removal, greatly reducing maintenance downtime and dry-docking costs during vessel operation.

• Deck Extension Type: Stem extended above deck to enable operation of bilge or ballast tank valves from deck, avoiding personnel entry into hazardous compartments.

• Bulkhead Penetration Type: Stem penetrates bulkhead to allow isolated operation from adjacent compartments or fire zones.

• Subsea Extension Type: Stem extended to ROV-accessible position or fitted with subsea actuators for operation of subsea manifolds.

• Insulated Extension Type: High-temperature service pipelines equipped with extended cooling stem to protect operators and sealing packing.

• Floating Ball (≤4"): Compact structure, low cost, reliable sealing under medium and low pressure conditions.

• Trunnion-Mounted (≥6"): Precise ball positioning, suitable for high pressure differential and large bore applications.

• Bi-Directional Sealing Design: Independent upstream and downstream seat sealing, unrestricted installation orientation, simplifying marine piping design and spare parts management.

• Optional Flanged / Butt Weld / Threaded Ends: RF flanged (ASME B16.5), butt weld (BW), socket weld (SW) and threaded (NPT/BSP) connections available to meet various marine piping system requirements.

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

• Anti-Static Device: Built-in anti-static spring ensures effective discharge of static electricity between ball, stem and body, preventing explosion caused by static accumulation in fuel or oil-gas service.

• Blowout-Proof Stem Design: Bottom-loaded stem with anti-blowout shoulder. The stem remains retained in the body even if the packing gland is accidentally removed, ensuring offshore operational safety.

Marine Grade Top Entry Ball Valve with Extended Stem 3D Diagram

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.