Pump purging issue
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I have currently come across a setup that includes bypass purge lines before and after the pump. May I ask, is it better to purge the pump from the front or from the back? The actual setup involves purging before the pump; could this result in incomplete purging?
Blow air in front of the pump; the pipeline behind the pump allows fluid to flow back to the inlet of that pipeline or to another device, and then it returns to the pump and enters the filter
Personally, I think it makes no difference whether you blow from in front of the pump or behind it. The purpose of purging is to remove any debris in the pipes that could affect the operation of the equipment. It is necessary to follow the equipment’s requirements regarding such debris as well as the relevant purging guidelines, to ensure that 1) no debris gets inside the equipment, and 2) for certain gas pipelines, target testing is carried out to ensure that there are no residues left after purging. As long as these requirements are met, it doesn’t matter where the purging is done
I don’t understand what you mean by these so-called pre-pump blowing and post-pump blowing. Our usual practice is to install blind flanges at the inlet and outlet of the pump to prevent mechanical impurities generated during purging from entering the pump. As for the Bypass, was it added specifically for purging? As long as no purging impurities get into the equipment, it doesn’t matter whether it’s before or after the pump.
It is to allow the liquid inside the pump to be cleaned thoroughly during pump maintenance. The pressure holding and pipeline purging before operation were not carried out using a pump
During piping after the installation of the new unit, blind flanges should be installed at the pump’s inlet and outlet, with only the pipelines at these points being purged. For the sections of pipe that cannot be purged due to the check valve, they have to be removed and cleaned manually.
When repairing a pump, I need to first purge the pump and the pipelines connected to it; otherwise, if liquid leaks out during the disassembly of the pump, it can easily corrode the anti-corrosion floor. I just found it strange that the design plans show purging before the pump; can’t it be done after the pump?
The pump inlet flange is disconnected; first, the pipeline ahead of the pump is purged to prevent weld slag or metal shavings from causing damage to the pump’s internal components such as the impeller. After the upstream section has been cleaned, the pipeline behind the pump is then purged. It is best to isolate the pump, and using a bypass line connected to both the front and rear of the pump for purging is the best approach, as this prevents damage to the pump due to gas pressure during operation.
Blind plates should be installed at the inlet and outlet of the pump, with only the pipelines at these ends being purged.
Blind plates should be installed at the inlet and outlet of the pump, with only the pipelines at these ends being purged.