JC offers also a large range of metal seated ball valves for different services (slurries, pulp and liquors, high temperature, abrasive or sticking fluids, control).

• Bubble tight sealing up to 327 ºC and Class V up to 500 ºC
• Low coefficient of friction
• Excellent sliding and running properties
• Hardens the complete surface of ball and seats

WHY METAL SEATED BALL VALVES ?

• High temperatures: above 260 ºC the use of soft seats is not recommended.
• Abrasive media: even small particles can damage soft seats.
• High Velocity in opening/closing cycles: this action can perfectly deform the soft ring and destroy the seat.

GENEAL HIGHLIGHTS

• Full and Reduced bore.
• Floating and Trunnion mounted ball.
• Soft and Metal seats.
• Castings Quality as per ASME B16.34 Mandatory Appendix I to IV in ASME valves and Severity Levels S3-V3 to DIN 1690 and EN 10203 in EN-DIN valves.
• Polished ball Ra 1 in soft seated valves (in metal seated valves ball is lapped); grinded stem Ra 1.6.
• Full traceability of shell components, upon request, ball and stem as per EN 10204 3.1.
• Antistatic device integral with the stem.
• Viton A, Aflas or Kalrez primary stem seal an secondary graphite packing.
• NACE MR.01.75 wetted parts and bolting as Standard.
• Fire safe as standard construction ISO 10947 : 2004 and
• API 607 : 3rd, 4th, 5th edition.
• Fugitive emisions EN-ISO 15848-1.
• SIL 3 (Safety Integrity level 3).

The post JC BALL VALVES appeared first on Sirimongkol Engineering & Supply.

Bodies and bonnets are high quality cast and afterwards precisely machined, directing the attention to prevent stress concentration.

The bodies of gate valves consist of a straight through port that guarantees minimal turbulence and resistance to flow.

In both designs, bolted bonnet and pressure seal, the bodies consist of guide slots to accommodate the wedge during opening or closing of the valve.

Bonnets are made either of one piece only –the yoke then being an integral part of it– or have two pieces, depending on the size of the valve.

This ensures the perfect alignment with the body what leads to an accurate opening and closing.

Backseat All JC gate and globe valves have backseat threaded in the bonnet,

or for the pressure seal valves, welded to the bonnet. Into pressure seal the hard facing is stellite 6 or equivalent.

Stem The stems of JC gate valves are forged from one piece and ACME threaded, then mechanized and finally provided with a smooth finishing in order to minimize friction.

In gate valves, the union of stem and wedge shall be in T form, designed to prevent the stem disengaging itself from the wedge while being in service.

This design includes a conical raised surface that presses the seat against the bonnet backseat in the fully open position.

Body and Bonnet Gaskets

The design of the body-bonnet/gaskets varies depending on the class of the valve. Class 150 gate valves consist of a square joint in 2″ and an oval one for all other sizes.

Depending on the valve service it can be supplied flat-face gasket with graphite or PTFE.

Class 300 and 600 valves consist of a circular spiral wound gasket. Class 900 and above gate valves consist of a ring type joint.

In pressure seal designs the sealing is achieved through a gasket that takes advantage of the internal pressure of the line.

The material most commonly used is high-purity graphite being located between the body and the body retainer ring.

Flexible Wedge

All JC gate valves 3″ and above valves feature a flexible wedge unless otherwise specified by the customer.

The flexible wedge shifts along the body of the valve during opening and closing, being held in position by a guide slot that minimizes the friction between body seat and wedge.

This design is especially suited to compensate slight thermal deformations produced by the pipe or the valve itself safeguarding a better sealing between body and wedge seats.

The post GATE VALVE appeared first on Sirimongkol Engineering & Supply.