thermal relief syste, on bonnet of wedge gate valve

[saj1507]

Any legends

which are the fcators that determine which size of gate valve should have thermal relief systems on bonnet or is there any spec that defines when to have this relief system?
We have been circulating the question of what size of wedge gates valves should require the thermal relief systems on the bonnets.

based on a temperature swing of say 30 degrees C?

 

[hsbcn]

hi there, saj1507:

within what temperature will the swing be 30ºC and what pressure levels are you looking to pass through the valve?


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