Can a shut-off valve be installed at the inlet end of a pressure vessel safety valve?
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The safety valves of our pressure vessels need to be calibrated regularly, but since the medium inside these vessels is liquid, it is not possible to remove the safety valves. Is it possible to install a stop valve at the inlet of the safety valve in order to allow for its removal?
In any case, root valves are not allowed to be installed on boilers
Many pressure vessel safety valves are equipped with a root valve in front of them: lol
It can be added, but it must remain in the on state.
We have used root valves in front of the safety valves of many pressure vessels, but it is necessary to ensure that they remain open at all times
It can be installed, but during the normal operation of the pressure vessel, the stop valve must remain fully open (either sealed with lead or locked). The design and diameter of the stop valve must not prevent the safe operation of the overpressure relief device.
Check valves cannot be installed at either the inlet or outlet of a safety valve; by examining the structure of check valves, it becomes clear that they will interfere with the safety valve’s ability to discharge pressure. Only valves with full flow capacity (such as ball valves or gate valves) can be used. Two valves must be installed on the bypass line of the safety valve: a ball valve or gate valve for shutting off flow, and a throttle valve for venting during equipment maintenance.
This post was last edited by *AOL_1 on 2018-3-26 at 11:08. Due to the requirements for safety valve certification, many installations now need to have two safety valves in the same location, with a root valve being necessary as well.
I’ve learned a lot; the explanation was very detailed. Thank you! !
Globe valves should be better than stop valves, right?
I’ve learned something new – I just checked the structure of those 3 types of valves, and indeed, globe valves should not be installed at the inlet and outlet of safety valves.