Trunnion Ball Valve

The ball on a trunnion ball valve does not move with medium pressure. Trunnion ball valves have floating seats. This valve uses pressure actuated seats with locked-in non-metallic face seals. To Assure tight sealing at low pressure, special springs force the seats against the ball. At higher pressure, the upstream seat is forced against the ball by the pressure working across the differential between the area of the seat insert and the seat O-Ring. The higher the pressure, the tighter the seal.

Cast Steel Trunnion Ball Valve

Technical Specification

Design and Manufacture : API 6D

Face to Face/ End to End : API 6D, ASME B16.10

Flange End : ASME B16.5, ASME B16.47

Butt-Welding End : ASME B16.25

Test & Inspection : API 6D, API 598

Main Materials

WCB, LCB, CF8(M), CF3(M)

A995 4A, A995 5A, A995 6A

Alloy 20, Monel, Inconel

Main Parts Material Sheet

Note : The Length of the bonnet extension of cryogenic valves shall be determined base on actual working temperature.

This will be omitted in the future design upgrade and changes.

Dimensions and Weights

Class 150

Class 300

Class 600

Class 900

Class 1500

Trunnion Ball Valve Torque Table

Note :

The torque measuring and calculation is based on normal room temperature, when selected seat material is PTFE/ RPTFE for Class 150/ Class 300 and Nylon for Class 600.

For low-temperature/ cryogenic service, the torque will increase 2 fold.

When sizing the actuator, a safety factor of 1.3 - 1.5 times shall be applied.

When the service or seat material is different than that specified above, the torque value will be different, it shall be subject to the conformation from the manufacturer.