Warming up arragement for pumps 2

[SENGUTTUVAN]

For the centrifugal pumps ,where the fluid temp is above 200deg c it is said a warming up arrangement is reqd to the standby pump from the running pump discharge. Some of the vendors say that they do not require warm up arrangement. How come for the same material of construction of the pump and its components , one vendor suggests for warming up and some others say No. what is the temperature above which we need to insist for warming up arrangement?

 

[BigInch]

I think warm up requirements would depend on the construction type of the pump, rather than temperature.

Certainly 200 C will cause some differential temperature stress and rapid material expansions, if slammed into a cold pump. I could see where knoweledgable pump vendors would be inclined to advise against cold starts. But then again, it could be a stress consideration, which for the same but thicker materials, could reduce stresses below limits, whereas thinner parts would have high stresses.

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"Pumping accounts for 20% of the world’s energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies)

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[Artisi]

In addition to BigInch's comments, I think that keeping the pump at operating temperature is advisable as it ensures that the pump/motor/pipework alignment is maintained and not subject to variations that are likely if the unit is standing idle in a cold condition, further, final alignments should be made with the pump at operating temp. in any event.

 

[SENGUTTUVAN]

Thank U biginch and Artisi.