Pump shaft and impeller

[vanuta]

Hi,
I am currently working on a project that involves specing out a bolt that would be used to hold an impeller to the shaft. I was wondering what are the forces that i should consider to spec out a suitable bolt. Thank you.

 

[Artisi]

Seems to me it will depend on the impeller / shaft / bolt sizes, how the impeller is mounted and the shaft to impeller drive arrangement.

More detail needed.

 

[TenPenny]

I think your biggest task will be to evaluate the thrust on the impeller, over the complete range of flows and speeds. That will depend a lot on the impeller design, vane style, and whether it has balance holes or back vanes, etc etc etc.

 

[wimple]

Consider also in the design the possibility that impeller run in reverse direction...

wimple

 

[rmw]

A very real possibility when pump motors are being 'bump' tested for rotation check.

rmw

 

[waross]

We had an installation where thermal shock would loosen the impeller nut on a boiler feed pump. Really bad operators who did not seem to be trainable. They had an annoying habit of hitting the feed pump with alternating hot and cold water. They eventually destroyed their boiler. They ran the boiler dry for so long and so hot that when they put water in the still hot boiler, instead of exploding, the multitude of leaks just quietly put the fire out.
By then I was long gone and I was not going back.

Bill
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"Why not the best?"
Jimmy Carter