Can the operating valve be used as an emergency shut-off valve?
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Here’s the situation: our oil depot stores gasoline, diesel, and aviation kerosene. There are two valves installed in front of the oil tanks; the one located closer to the tank (what we call the tank base valve) is a manual gate valve that remains open at all times, while the second valve is an electrically operated valve that is used for regular operation. The oil depot plans to upgrade its automated control systems, and it was specified in the design that the electric valves used for operation cannot be used as emergency shut-off valves. However, the \"Basic Requirements for Emergency Shutdown Systems in Oil and Gas Storage Enterprises (Trial)\」do not include any requirements in this regard. Are there any regulatory requirements for this approach to design?
There are requirements regarding the shutdown time of the emergency shut-off valve
Since electric valves cannot close the valve in the event of a power loss, conventional valve closures (shut-off valves) take all possible situations into account, and are equipped with manual operation or rely on the pressure energy within the pipeline to close the valve.
No, the emergency shut-off valve requires a TSO for tight closure. Conventional operation valves have a high leakage rate.
An emergency shut-off valve is required in the SIS system. It is not the same system as a regular DCS. Ensure protection in special circumstances
Many documents require compliance with GB50160, GB50770, GB50074, AQ3053, SHt3007, as well as documents issued by the Work Safety Supervision Bureau
Oil depots have different levels of risk compared to conventional production facilities, so higher requirements are applied
The operating valve cannot be used as an emergency shut-off valve; the emergency shut-off valve is controlled separately by the SIS system
What is the SIL rating for the isolation valve? Is there a rating report available? Use the SIL rating indicated in that report to select the appropriate valve – it’s not possible to just pick any valve and use it. The signal must be fed into the SIS system, which is independent of the DCS; the SIS is responsible only for shutting down and isolating processes, and its working principle differs from that of the DCS. In short, the reliability requirements for it are higher than those for components in the DCS.
In many designs, the tank root valve serves as an emergency shut-off valve, which can be operated manually. I haven’t heard that remote control is necessary
The operating valve cannot be used as an emergency shut-off valve