Purging of pump inlet and outlet pipelines

1. For purging a newly installed unit, if a container at the inlet is used to purge the pump, is it by disconnecting the flange connected to the pump body and discharging the fluid? If that’s the case, does the filter at the pump inlet need to have its filter element removed? The connection flanges should be disconnected, and the filter should also be purged; when purging a newly installed unit, no dead corners should remain. 2. For the pump outlet, is it done by using a container downstream to create pressure for backwashing, or by disconnecting the flanges connected to the pump body to allow discharge? If that’s the case, does the one-way valve on the outlet need to be reversed? Same as above. The check valve also does not need to be reversed. 3. If there is a minimum flow line between the upstream side of the pump’s outlet check valve and the upstream side of the inlet filter, and there is only one valve in that line, then how can this line be purged? After all, once the flanges at the pump’s inlet and outlet are separated, it becomes impossible to maintain pressure in that line Purging and pressure holding can be carried out in two steps: lol

For purging a newly installed unit, if a container at the inlet is used to purge the pump, is it by disconnecting the flange connected to the pump body and discharging the gas? If that’s the case, does the filter at the pump inlet need to have its filter element removed? Yes, for the pump outlet, pressure is stored in a downstream container and used for backflow; so is it by disconnecting the flange connected to the pump body to discharge the fluid? If that’s the case, does the one-way valve on the outlet need to be reversed? It would be better to replace the check valve with a short pipe, so that it can be cleaned thoroughly. If there is a minimum flow line between the upstream side of the pump’s outlet check valve and the upstream side of the inlet filter, and there is only one valve in that line, then how can this line be purged? After all, once the flanges at the pump’s inlet and outlet are separated, it becomes impossible to maintain pressure in that line The flange of the minimum flow line is disconnected, and a container at the inlet is used to purge the pump

What the moderator meant by “it’s impossible to hold back the pressure” is probably that it’s not possible to control the purging pressure after the flange is disconnected, right? It is recommended to use blind flanges to isolate the inlet and outlet pipelines from the pump; the bolts used to secure the blind flanges do not need to be tightened all the way, leaving a slight gap. This not only isolates the pump but also allows for some control over pressure.

Disconnect the pipeline and install blind flanges; remove the check valves and instruments

All fittings that are prone to clogging should be removed. When blowing out, iron plates should be used as separators.

I’ve learned it; from the answers given by those above, I have found the answer – it needs to be blown into every place. However, the filter at the pump inlet should be purchased clean; is it possible to avoid blowing it? The pipeline between the top vapor line and the cooler is 400 mm in length, and there are no valves at either end – how should this be handled?

The principle of purging is to prevent impurities in the upstream pipelines from entering the downstream equipment. If it is feasible to disconnect the flanges for purging at various stages in the process, and if the process layout permits, it is necessary to first disconnect the pump inlet flange and the filter, purge them thoroughly, and then reattach them before proceeding with the purging of the downstream sections of the process；