Hi folks, can someone please help me with negative (gauge) pressure scales and vacuum? I know -1 bar gauge is 1 bar below atmospheric -vacuum (or almost) but does it make sense to say that a pressure gauge is ranged from 0 to (minus 2.5 barg)? If so what does this mean?
Thank you guys for your assurance, I guess we'll stick to that rule of thumb then. BTW the service is H2S gas service and I will classify the valve as doing a shutoff/plant segregation function hence the safety case might apply. we have recently discovered that timing problem is the least of...
We are converting a 24" HV (rotary)to an air actuated shut down valve. Is it Ok to apply same rule of thumb (approx 1s per inch) for closure time as control valves to a shut down valve? Our process guys seem to be OK with this but I think we should specify a faster closure time, any guidelines...
Hello,
This is my first SD valve design activity and I need to approve the GA drawings for the selected actuator (air operated,Eex d, Worm Gear or similar, mounted on the valve at an angle). I'll just like to know if there any standard or usual points to look out for in accepting the vendors...