Breakaway torque for ball valve
Breakaway torque for ball valve
(OP)
Hi everyone!
Can somebody explain to me how to calculate the breakaway torque for ball valve particularly for 2 inch - class 150 ball valves. The material for seat is PTFE and the ball is made up of ASTM A105. Thanks!
Can somebody explain to me how to calculate the breakaway torque for ball valve particularly for 2 inch - class 150 ball valves. The material for seat is PTFE and the ball is made up of ASTM A105. Thanks!





RE: Breakaway torque for ball valve
Hello jethrolawing!
I would recommend you to check previous discussions on the topic in this forum and others. I believe the answer is already given there.
Torque is normally measured (not calculated) under (simulated) operating conditions, and will vary with a factor of at least 1:3, others will say 1:5 or 1:10 in 'real life.'
So: what is the purpose of your calculation? Giving the normal torque in continious operation by a 'nice' fluid, for instance pure, thin oil without impurities, or selecting the construction details for the spindle top when applying a 10-times normal force?