Problems with the centrifugal pump outlet check valve
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I would like to ask the classmates whether a check valve needs to be installed at the outlet of every centrifugal pump Give an example to illustrate
1. Pipes with a diameter larger than DN50 generally require installation. 2. It should be installed to feed from low pressure to high pressure.
The function of a check valve is to prevent liquid in the pressure water pipeline from flowing back into the pump when the pump stops operating, which could cause the rotor to rotate in the reverse direction, damaging the equipment or leading to a sharp drop in pressure in the pressure water pipeline. Therefore, a check valve needs to be installed.
It’s usually installed, but there are also cases where things don’t follow the usual pattern
Check valves must be installed at the outlet of centrifugal pumps to prevent the medium from flowing back into the pump, which could cause the impeller to rotate in the reverse direction and potentially damage the bearings.
A check valve must be installed, primarily to prevent the liquid at the outlet from flowing back, which could cause the impeller to rotate in the opposite direction and lead to issues such as loose impellers. It also results in a loss of pressure head for a portion of the high-pressure liquid.
It is said to be necessary, but the centrifugal pumps used in rural areas have a faucet with a check valve at the inlet, but none at the outlet
It should be installed; all pump outlets of ours are equipped with check valves
It is advisable to install a check valve at the outlet of a centrifugal pump; however, for fluids containing impurities, the normal service life of a check valve is generally short. Therefore, I personally believe that a check valve is not necessary at the outlet of the centrifugal pump, in order to avoid additional resistance in the event of a failure of the check valve.
A check valve should be installed as a matter of common sense to prevent liquid from flowing back and causing unnecessary losses.
All centrifugal pumps at our factory are equipped with check valves at their outlets. It is probably to prevent liquid from flowing back and causing damage to the impeller.
A check valve must be installed, primarily to prevent the liquid at the outlet from flowing back, which could cause the impeller to rotate in the opposite direction and lead to issues such as the impeller becoming loose.
Generally, the diameter of the outlet valve is 50 smaller than that of the inlet valve, and a globe valve is installed before the inlet valve.
A check valve must be installed, primarily to prevent the liquid at the outlet from flowing back after the pump stops, which could cause the impeller to rotate in the opposite direction and lead to issues such as loose impellers and damaged mechanical seals.
To the student who replied “9th floor”: The check valve installed at the inlet of the water pump used in rural areas serves to fill the inlet pipeline with water when starting the pump, so that the pump can be started successfully
A check valve needs to be installed, and a shut-off valve should be placed after the check valve.
It generally needs to be installed. However, practical testing has shown that not installing it has no impact at all. On the contrary, don’t place too much trust in check valves; nine out of ten of them don’t close properly.
Installation follows standards; operation relies on skill. Standards are meant to prevent human errors and reduce the likelihood of accidents; install it if you can! It is mainly to prevent the liquid exiting from flowing back and causing damage to the pump; proper operation poses no problem. Another option is that it’s not necessary to install it if the outlet pressure isn’t high.
Generally, check valves must be installed when the pipe diameter is above DN50, or the flow rate is above 20 m³/h, or the pressure is above 0.2 MPa. Without a check valve, a sudden stop of the pump will inevitably cause it to rotate in reverse, thereby damaging the pump. For pumps with small diameters, low flow rates, and low head, the absence of a check valve has minimal impact, but it is still advisable to install one. However, after installing a check valve, one issue to keep in mind is that for flammable, explosive, or hazardous media, it is also necessary to consider draining the medium from the pipes during shutdown and replacement processes.
It must be installed at the pump outlet connected to the system, to prevent high pressure from leaking into the low-pressure side in the event of a shutdown. This prevents the pump from rotating in reverse and damaging its mechanical components, as well as avoiding a loss of system pressure.