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Why do we spend so much time on pump shafts? Because we realize the important role they play in the life of a pump. Though it is a seemingly small part of the pump, we consider the shaft critically important and we take the time to make it right.

Imbalances and vibrations in a pump can increase wear and result in reduced impeller, bearing, mechanical seal - or ultimately - pump life. This can be caused by poor machining or inaccurate measurements. To avoid these problems, we build our shaft assemblies within very tight tolerances. Building a smooth running pump starts with precision machining.

The long, hexagon shaped shaft is cut within three-thousandths (.003) of an inch of the desired length. Once the length is verified, each shaft is placed into a steel sleeve and checked for straightness. To pass, the shaft must be within four-thousandths of an inch straightness from end to end. If it does not fit the 0.004” tolerance, it is adjusted to spec.

Much like the shaft, the shaft coupling must adhere to tight tolerances. The coupling, which connects the motor to the shaft, is a two-part component. To ensure a tight fit to the motor, the inside bore depth of the inner coupling is eight-thousandths (.008) of an inch tolerance. It is pneumatically pressed into the outer portion and drilled and tapped to accept a stainless steel pin that secures it to the shaft.

We can be confident that when our impellers are installed onto these shafts, we are producing quality pumps with a long life span.