Motor end /axial play ????

[pkg80]

hello

can any one suggest the minimum and maximum axial/end play for the induction motor with antifriction bearing. If axial play is more what may be the bad effect on the equipment ?

 

[1gibson]

Depends on the size, and the amount of thrust.

If it moves more than is allowed by the mechanical seal (typically +/- 0.015" to 0.030") then it can cause the seal to leak or cause damage.

 

[Artisi]

What equipment, what size motor etc etc?
And besides, you should check with the motor manufacturer, not ask Eng-Tips questions without giving any information, we have some pretty bright people here, but mind reading isn't one of our strengths.

It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)

 

[pkg80]

hello Artisi /1gibson

Thanks for reply

This motor drives the pump which is using for propane transfer.
Motor power =200HP
RPM=1800
Motor bearing : Antifriction bearing
Arrangement of equipment : Horizontal

I want to know the general thumb rule or whatever the method to decide the best axial paly for the induction motor (For both case horizontal and vertical).

 

[Artisi]

ask the motor manufacturer what is acceptable and then review the coupling element between the driver and the driven unit to see what is acceptable as end float , not only the motor but also the pump.

It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)

 

[MikeHalloran]

There are no pro-friction bearings, so 'antifriction bearing' tells us nothing.
There must be thousands of major types of antifriction bearings.
You need to get in touch with the motor manufacturer and find out exactly what bearings are to be supplied.
The bearings at each end of the motor are usually different, to allow for differential thermal expansion.

The bearings will be still different if the motor is specified for use with the shaft axis vertical, because motor manufacturers use the cheapest bearings possible, so the default, for shaft axis horizontal, is bearings that cannot support the rotor's weight when the shaft is vertical.

Mike Halloran
Pembroke Pines, FL, USA