Closing time requirement for the expander inlet quick-close valve
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API 670 provides requirements for overspeed protection of expanders; what are the requirements regarding the closing time of the quick-close valve at the inlet of the expander? Are there any explicit statements regarding time that can be found in public standards or documents?
This post was last edited by CHANGBAISHI on 2023-3-14 07:36. Cutting off the air supply in just one second will ensure that the equipment is not damaged. A couple of seconds is fine. Its principle involves using instrument air to act on the diaphragm of the valve actuator; once power is lost, the solenoid valve activates, instantly switching the air supply and releasing the pressure in the cylinder, causing the valve to close immediately due to the action of the spring. If looking for standards, it is best to seek industry standards from the equipment manufacturers or valve manufacturers. It probably doesn’t serve any practical purpose either. For reference.
You may refer to JBT 11490-2013: Quick-Closing Butterfly Valves for Turbines. Section 3.1 defines a quick-closing valve as a valve that can be rapidly closed within 0.3 s to 1 s starting from the moment a signal is sent from the system.
Air source – it was written as “origin”; my apologies;P