Regarding whether the cut-off valve should be equipped with a manual/automatic switching function
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At present, there is a problem with cut-off valves: when selecting such valves, the plant management focuses on increasing the operational rate of interlocks, and therefore chooses valves that do not have a manual/automatic switching function. However, this poses a significant risk – as part of the production facility, an incorrect operation of a cut-off valve can lead to shutdowns of the facility. Everyone is free to share their opinions; since the existing cut-off valves lack this manual/automatic switching function, and at the same time it is not allowed to disable the interlocks, is there any way to solve this issue?
For cylinder-type control valves, shut-off valves, and interlock valves that lack front and rear hand valves as well as bypass valves, we provide handwheels.
Could we consider adding a second confirmation step in the control system? Personally, I think it would be better to include a handwheel.
This post was last edited by seiluobin on 2016-5-4 at 08:55. First of all, proper management is required; if interlock functions are disabled, it is necessary to file a report, and the configuration screen will always indicate that such interlocks have been disabled. Secondly, the switch valves used for interlocks are designed to be used at the moment when an interlock is triggered. As for the concern raised by the original poster regarding accidental activation of interlocks, I would say that considerations related to accidental activation pertain to the SIS or the entire circuit, and it’s not something that can be prevented by using accessories on the valves. The probability of a person operating the handwheel correctly and in a timely manner is much lower than the already very low probability of accidental interlock activation. Alternatively, you might consider whether a superalloy steel protective cover is needed for the entire device in case of a meteorite impact