5 Features of Trunnion Mounted Ball Valve

The followings are 5 features of trunnion mounted ball valve:

 

1. Easy operation: The ball is supported by upper and lower shafts, reducing friction and eliminating exaggerated torque caused by large sealing load due to ball driven by inlet pressure and sealing seat.

 

2. Reliable sealing: Sealing ring made from PTFE is inlayed in the stainless steel seat. A spring is set at the end of metal seal so that sealing ring has enough preload. With the spring, the valve can maintain its good sealing performance even though the sealing face is worn.

 

3. Fire proof structure: In case of PTFE sealing ring being burned because of shock heating and fire, resulting in leakage and encouraging fire behavior, a fire proof sealing ring is set between ball and seat. When the sealing ring is burned, sealing ring on seat is rapidly pushed to ball with spring force, forming metal-to-metal sealing and a certain degree of sealing performance. Fire resistance test confirms to API 6FA and API 607 standard. 

 

4. Self-relief performance: If pressure of media remained inside mesocoele of the valve rises abnormally and exceeds preload of spring, seat retreats and breaks away from ball to realize self-relief. Seat resets automatically after self-relief. 

 

5. Drain line: There is a drain hole on top and bottom of body, used to check leakage occurring on seat. When valve is full on or off, packing can be replaced directly after taking off pressure in mesocoele. The drain hole also can be used to relieve rentates, alleviating pollution of media to valve.