To flush a bearing housing with new grease, driving out old, contaminated or incompatible grease until clean product appears at the relief or drain. Purging is the standard way to change grease types or recover from water ingress. It is done with the relief plug removed and ideally with the machine running, or the pressure will blow the seals, and motors are left running with the drain open afterward to shed the excess.
Pull the drain plug and purge it till clean blue comes out, then let it run open for half an hour.
Also heard as
- purging
- flush
Related terms
Grease compatibility
Whether two greases can be mixed without losing consistency, dropping point or stability.
Overgreasing
Pumping more grease into a bearing than it needs, causing churning, heat and blown seals.
Soup
Grease that has broken down or been mixed with an incompatible type and turned runny.
Zerk
Everyday name for the small ball-check grease fitting that a grease gun coupler snaps onto.
Same word, different worlds
To run adhesive through a mixer or dispense valve and discard it, clearing old, unmixed or off-ratio material.
Welding, Brazing & NDEInert gas flowed inside a pipe or behind a joint to keep the back of the weld from oxidizing.
Boilers & BurnersBlowing air through the furnace and flue before ignition or after shutdown to clear out unburned fuel.