Pump interlock automatic control
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I would like to ask an expert: regarding pumps that operate in one active and one standby mode with interlock automation based on pressure, in all the cases I’ve seen before, there were pressure transmitters at the outlets of both pumps, and automatic control was achieved through interlocking based on the pressures of these two pumps. To simplify things, my unit has installed a pressure gauge on the main pipe at the pump outlet; the automatic start and stop of the pump are controlled based on the readings from this pressure gauge. Is it okay?
It’s fine to install it on the main pipe, similar to the pressure measurement point for the lubricating oil pressure in the unit; however, it’s better not to use the readings from the pressure gauge as a signal, as pressure gauges are prone to errors and damage
Refer to the fire pressure stabilization pump for setting, and choose reliable instruments. Feasible.
Using pressure signals and appropriate circuits, any pump can be controlled. It mainly depends on the requirements of the manufacturing process.
It is recommended to use an up-converter for pressure-interlocked pump start/stop; otherwise, the equipment is prone to damage! :)
A pressure transmitter can be installed on the outlet manifold; it’s advisable to choose an imported transmitter as it generally offers better quality, such as the Rosemount 3051 model, which costs around 3,200 yuan
One in use and one as backup is fine, but as mentioned above, I really don’t understand why chemical processing plants prefer to use pressure interlocks
Generally, chemical processing units implement interlock systems based on several common parameters, and this is normal! Actually, in the case of one in service and one as a backup, I’ve also seen operating signals being used as a interlock mechanism! The start/stop function is quite timely and effective!
It’s not that interlocking isn’t possible; it’s just that using the \"pressure\" variable is rather pointless and not the optimal approach. As designers, it’s difficult to determine the right approach in such cases, which is why people complain about the need for such a setting
Yes, that’s why I said that in some places using a running signal as a condition is faster and more direct!
From the perspective of system safety and stable operation, installing a return bypass and using pipeline pressure to control the amount of return flow is more conducive to maintaining system pressure stability and extending the lifespan of the equipment. Shutting down the pump directly can cause significant damage; moreover, whether the pump can be started again after shutdown depends on the actual conditions on site and the piping layout. Therefore, pressure-driven sequential pump shutdown is not recommended; instead, it is preferable to install a return bypass to control the flow rate and maintain the pressure in the system pipes