Vihung - Model API 6D -Trunnion Mounted Ball Valves
Trunnion valves have mechanical anchoring of the ball at the top and the bottom to avoid axial displacements in the flow direction. During normal operation pressure compresses the seat onto the ball to achieve valve sealing, such construction also ensures automatic cavity relief in case of overpressure in body cavity. As isolation valves, they intercept the flow by opening and closing the port and are mainly recommended on tight shut-off gas and liquid services; trunnion control valves with cage trim are engineered for those services where continuous pressure and flow rate regulation are required.
Vihung trunnion ball valves are suitable for a wide range of applications and pressures up to 2500 bar and temperatures down to -196°C (-320,8°F) or up to 850°C (1562°F), with sizes range from !4" to 72" with double block and bleed design, metal and soft seated with SIL-3 capability safety rating, engineered for cleaning tools usage with fast and reliable operation. Most designs are double seated but special single seated and X-TRIM solutions for severe and critical services can be also supplied for rising stem (RSBV) or eccentric ball valves providing many features and options beneficial for oil, gas and liquid applications.
There are three main body constructions: side entry, top entry and multiple way. The main difference is based on how the pieces of the valve are manufactured and assembled, from the side or from the top, operation is the same in each case: operating positions for 2-way valves can be either closed (no flow goes through) or open (fully or partially). Multiple way valves (3-way, 4-way or more) have different combinations of flow to serve many different functions: mixing, diverting or isolating and simultaneously bypassing.
Trunnion Ball Valve Side Entry Split Body.The valves suitable for Oil & Gas production, processing, transportation, distribution, chemical and petrochemical refining.
MATERIALS OF CONSTRUCTION:
- Low Temperature and Low Alloy Carbon Steel
- Stainless steel, Duplex and Super Duplex
- Nickel alloys
- Titanium
- Bronze
- Body Material: A105,A350 LF2.A182 F304/F316/F316L/F317/F321/F51/F51/F53/F55
- Ball and Stem Material: ASTM A182 F6A/17-4PH/XM-19/A182 F51/A182 F53/A182 F55
- Seat: RPTFE/DEVLON/PEEKA/ITON/METAL TO METAL
EMERGENCY SEALS:
For trunnion mounted ball valve size NPS 6 (DN 150) and above, it comes with provisions for sealant injection on both the stem and seat while for sizes NPS 5 (DN 125) and below on body cavity. In case of failed underperform seals, a temporary emergency seal can be achieved by injecting sealants.
ANTI-STATIC:
Because the ball and stem in a ball valve are suspended on non-metallic parts, i.e. the seat seal and stem seal, there is a possibility a static charge may build up on the stem-ball, a mechanical (antistatic metal spring and ball) is introduced in the design to maintain the metal-to-metal contact between the rotating ball/ stem and the valve body which will ground any charges to the valve body
BLOWOUT PROOF STEM:
The valve stem is made with a shoulder at the bottom end. It`s securely retained by the stuffing box, to avoid that the stem, under certain operating conditions, accidentally blows out. Other designs are available on request.
FIRE SAFE DESIGN:
During a fire, non-metallic soft material will be burnt, subsequently seat leakage or external leakage may occur and cause the fire spread or contaminate the environment. Our ball valves are fire tested in accordance with API 6FA or API 607, witnessed and certified by TUV SUD. If valve is not covered according to the standards, they are designed to be fire safe
