In the case of sequential cut-off feeding, can a control valve be used as the actuator?
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This post was last edited by RSchufaqi on 2023-2-10 09:46. As the title suggests: From a compliance perspective, in the scenario of sequentially shutting off feed streams, can a control valve be used as the actuator? Automatic control instruments
Personally, I think it’s not possible; rapid cutting off is required, and control valves cannot achieve this.
If pneumatic control is required, an electromagnetic valve must be added to the control valve to ensure that it can operate even in the event of a power outage or loss of air supply
It depends on the specific circumstances. 1. If the pipe diameter is relatively large, solenoid valves likely don’t come in such large diameters ； 2. If a significant force is required to close the valve (for example, when there is a high pressure drop across the valve), the solenoid valve is likely unable to provide sufficient closing force ； At this point, it is possible to consider using pneumatic control valves (cylinder valves, diaphragm valves, etc.) in combination with solenoid valves to switch the air path and thereby shut off the pneumatic control valve.
It depends on the occasion. It’s better to add a switch valve as well.
For sequential cutting, choose a on-off valve; the specific choice depends on the process requirements
A control valve can be used, but its leakage rating must be level 6.
It is possible to add solenoid valves on the DCS, but not in the SIS system; an additional isolation valve is required, as a single control valve cannot ensure complete closure
This post was last edited by RSchufaqi on 2023-2-12 at 14:02. Would it work if we use a control ball valve instead? Performance can be improved in terms of leakage level and response time, at the cost of adjustment accuracy.