ESDV Emergency Shutdown Valve Specifications and Standards
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Do any experts have the specifications and standards for emergency shut-off valves? Currently, the ESDV valves come in a 42-inch size, and they close after a delay of several seconds; the valves shut down in case of a fault. The manufacturer says that these valves are active during those few seconds, but it’s not visible to the naked eye. This is clearly not correct, so I’m hoping that experts can help identify any relevant standards or specifications in this regard.
Due to the water hammer issue, the required valve closing time is currently 60 seconds; however, no visible movement occurs during the first twenty-odd seconds, and the valve only begins to close slowly in the subsequent forty seconds.
I’m not sure where the standard specifications come from, but in general, if there are strict requirements regarding the shutdown time, it is the process engineering department that determines this value. Otherwise, for larger valves, the shutdown time is usually determined based on the valve diameter – it should not exceed 3 seconds per inch. It would be great to be able to shut down a 42-inch valve in just 60 seconds!
Firstly, there are no provisions in foreign and domestic standards and regulations that specify requirements regarding the shutdown time； Secondly: the shutdown time should be determined based on your own process conditions, overall process safety, and equipment safety. Configure the relevant attachments and equipment to ensure that the valve reaches the closed (open) state within the specified time!
I am studying control valves; the Fisher control valve manual mentions dead zone and response time, such as the reasons for the dead zone, including the torsional friction of the shaft in angle-type valves and the friction of the packing in linear-type valves. Of course, the on-off valve has the same problem. Just my personal opinion.
How fast do you want it anymore? Wish I could turn it off right away? Can the valve stem and valve body withstand such high torque? ! :lol
It mainly refers to the issue of delayed shutdown by 20 seconds, the response time of the valve – the valve takes 20 seconds before it reacts
There is indeed this issue, which relates to overcoming friction; it’s not clear whether 20 seconds are required for that. Such valves generally operate in a closed state when there is a fault
When selecting a product, the sample provided by the manufacturer indicates the duration that should be maintained； Choosing the wrong option is the designer’s responsibility; if oversight occurs during construction or inspection, joint liability applies ； When we encounter situations lasting more than 2 seconds during construction, we seek guidelines from the relevant departments.