Problems with pumps are rarely caused by the pump itself. Process conditions and human error are far more likely the case. This week, we reached out to the Quality Manager from LobePro pumps for examples of ways others have killed their rotary lobe pumps. Read the list below, then download our new resource, "27 Ways To Kill A Positive Displacement Pump" for even more examples.
SEAL FAILURE, INTERMITTENT USEIf you're pumping fluid that can solidify inside the pump when not in use, be sure to flush the seal before start up. Not doing so will destroy seals and o-rings, not to mention the lobes themselves.
NOT FILTERING / STRAINING / SCREENING PROCESS FLUIDYou spend a lot on your pumps, protect them with some form of filtering upstream. In this example, a screen had been in placed, but was removed. Solids got into the process fluid, breaking strain bolts, and destroying the lobes.
Be sure to protect your investment with a strainer, screen, or filter. The inital cost of the equipment is minimal compared to the cost of downtime and pump repair!
IMPROPER SCREENINGWe talked about the importance of using a screen before the pump, but what's just as important is to make sure it's the right one for your application.
This example shows a lobe with premature wear due to improper grit removal. Early lobe replacement was needed.
OVER PRESSURED LIP SEAL
When a rotary lobe pump (or any positive displacement pump) are operating against plugged discharge lines or closed valves, pressure builds in the line. A centrifugal pump will cavitate in these cases, but a positive displacement pump will continue to build pressure until something gives. In this case, a failed lip seal.
There's no magic bullet for preventing all unneccesary pump repairs. But you can help prevent them by reading the pump manual and training your operators in proper maintenance and installation techniques.
Want to see more positive displacment pump failures? Check out our latest resource "27 Ways To Kill A Positive Displacement Pump"!
Struggling with problem pumps? Ask us about it! We gladly provide technical assistance to businesses and municipalities in Wisconsin and upper Michigan.