Safety valve issues
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Reason why gate valves are used instead of globe valves for the safety valve bypass
A safety valve is not equipped with a bypass when it is functioning properly. If a safety valve has a bypass, it means abnormal pressure release occurs; the advantage of using a gate valve is that its opening degree can be easily controlled, whereas a globe valve cannot achieve this
The bypass is used for abnormal pressure relief; when using a gate valve, flow rate should be taken into consideration
If the discharge flow rate is considered. Globe valves are better than gate valves for controlling flow
Globe valves have better sealing performance than stop valves, which are prone to leakage.
Apart from the control valve bypass lines, stop valves are rarely seen in our installations.
Gate valves can be opened and closed quickly, with low operating torque； Globe valves have high driving torque and open slowly, and are generally used for flow control. The secondary purpose of the safety valve design is to allow for rapid pressure release, rather than for pressure control; therefore, gate valves are preferable to globe valves. Additionally, gate valves are more cost-effective than globe valves.