What is the function of the manual valves before and after the control valve? When to use it?
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What is the function of the manual valves before and after the control valve? When to use it?
Most control valves come with a bypass design, which is used to isolate the valve for repair when it fails.
1. During online maintenance, turn it off to facilitate maintenance. 2. When the parameters selected for the control valve are too high, it can be adjusted slightly lower to improve the control performance of the valve
Use for maintenance or for flushing during the first start-up
Bypass: When the control valve needs maintenance, close the upstream and downstream manual valves and use the bypass to allow material flow, so as not to disrupt production
Yes, especially those cases where the actual operating load differs significantly from the designed operating load. The process parameter deviations are large. It improves the reliability of the control valve.
1. In the event of a control valve failure, isolate the control valve for maintenance; a bypass for the control valve must be used in conjunction with it； 2. During system maintenance, local energy isolation can be achieved using manual valves, as control valves cannot serve this purpose.
Fault open valve, used to regulate flow!
1. For use during maintenance, 2. Bypass control valve