bmoorthy,
First, all valves need body bleed; the trunion mounted ball valves aren't doulbe block because rotating the ball (close-open or open-close) the pressure is retained only by the body.
Trunion ball valve designer.
Regards
There are many manufacturers spacialize on actuation of all types of valves, who can fulfill your needs. ( BRAY, AUMA, ROTORK etc.).I'm sure that you find something for you there. Take attention to flange connection between valve and gear box, the nominal torque of the gear box and the...
We use the Barierta LP from Kluber (Germany)
It is a PTFE base grease. I think is the best that you can find in Europe.
Another otion is greases from Tecnolubeseal (Italy)
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