one-way valve
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I would like to ask the experts: why are the check valves at the outlet of the pumps in refineries installed before the pump’s outlet valve rather than after it? The sequence is pump – check valve – outlet valve. If there are any issues with installing it after the outlet valve, I would appreciate everyone’s insights
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Our pump outlet check valve is located behind the pump outlet valve.
Our pump outlet check valves are installed both in front of and behind the pump outlet valve.
The main function of a check valve is to prevent the raw material from flowing back and causing damage to the pump. So, I think it doesn’t matter whether to install it or not.
Generally, large design institutes such as Luoyang Institute and Beijing Institute follow standard design practices, installing one check valve behind the outlet valve for each pair of pumps. Recently, I have seen some devices designed by smaller design institutes, which are rather ridiculous – a check valve is installed for each pump, and all of these valves are placed in front of the pump’s outlet valve.
Those installed before the outlet valve allow for easy replacement in case of a failure of the check valve, but they are costly as two units need to be installed. If the cost is reduced by installing it after the outlet valve, it becomes a problem once the check valve’s disc falls off.
Reply to 8# Canghai Hengliu: But from an operational perspective, it’s probably better to install one valve in front of each one, right? ? ?
With my limited knowledge, I have seen some devices designed by the Beijing Office, the Luoyang Office, and the East China Office, but I have not yet seen a pump with a check valve located after the outlet valve. From a safety perspective, if the check valve is located after the outlet valve, in the event that one of the pumps has a faulty outlet valve, fluid could flow back directly. I hope some knowledgeable experts can explain the design concepts behind the two installation methods, as well as their respective advantages and disadvantages.