gregorgws
Mechanical
- Apr 25, 2010
- 1
I have shaft that requires a 1.25" nomimal key. I am trying to understand B17.1 so i can specify the shaft, hub and key dimensions and tollerences and ensure i don't have an interference fit key.
Applying ANSI B17.1
Depth tolerance for class 1 fit per table for Standard fits for Parallel keys.
Key +0.000 to - 0.003
Shaft keyseat +.000 to - 0.015
Hub keyseat +.010 to -0.000
Fit range 0.033 clearence to 0.005 clearence
How are they calculating there fit ranges??? I cannot get the math to work.
To me, max clearence would be largest keyseats with smallest key
= .01 oversized keyway with .003 undersized key
= .013 Clearence
Minimum clearence would be smallest keyseats with largest key
= .015 undersized key with nominal key
= .015 interference fit
Applying ANSI B17.1
Depth tolerance for class 1 fit per table for Standard fits for Parallel keys.
Key +0.000 to - 0.003
Shaft keyseat +.000 to - 0.015
Hub keyseat +.010 to -0.000
Fit range 0.033 clearence to 0.005 clearence
How are they calculating there fit ranges??? I cannot get the math to work.
To me, max clearence would be largest keyseats with smallest key
= .01 oversized keyway with .003 undersized key
= .013 Clearence
Minimum clearence would be smallest keyseats with largest key
= .015 undersized key with nominal key
= .015 interference fit
