Shaft and impeller fit

[moiz19670309]

What is the general rules for shaft and impeller fit. I have a straight shaft who's outer measured diameter is 97.4 mm. The shaft has a key 12 mm key way. At this dia a impeller fit on the shaft with this key. I don't have the hole dia of impeller.
I want to make a new shaft. What dia and tolerance I should apply on the shaft to have the impeller seated in.
Any helpful document or table please.
Moiz Khan

 

[geesaman.d]

There are no general rules.

Also we don't even know what kind of impeller and shaft. Boat, pump, mixer, fan, steam turbine, ...?

 

[moiz19670309]

Dear Geesaman
The pump is Boiler Feed Water Pump, vertical type.

 

[Wuzhee]

There are many textbook examples on different fit types for different applications. Keys and keyways usually are loose fit to enable manual assembly. However applications which require more torque transfer are intermediate/tight fit that requires force and special tools to assemble.
Overlap is also very important to get right. Your base question lacks a lot of information necessary to give any helpful advice.

 

[jassco]

Hi, moiz19670309:

You should look it up in Machinery Handbooks.

Best regards,

Alex