Bearing clearance
Bearing clearance
(OP)
I have a Gear box that I am getting contradicting opinions on. The output shaft has a spherical roller bearing on it with a spec internal clearance of .005 to .008 in. If i push on the shaft I get .001 axial movement, which is to the gearbox manufacturers spec.
When I pull up on the shaft it moves .008 in. Which my gearbox manufacturer says is too much. The OEM bearing that the gearbox came with was an SKF. When I contacted their technical department they said they would expect that sort of movement in their bearing.
Which one is right? Has anyone else had any similar experiences? Am I even in the right part of the forums?
Thanks
When I pull up on the shaft it moves .008 in. Which my gearbox manufacturer says is too much. The OEM bearing that the gearbox came with was an SKF. When I contacted their technical department they said they would expect that sort of movement in their bearing.
Which one is right? Has anyone else had any similar experiences? Am I even in the right part of the forums?
Thanks





RE: Bearing clearance
If the gearbox manufacturer says that's too much, then they have a design problem. They spec'd the wrong bearing.
Make sure you and both manufacturers are talking about and measuring the same parameter as they each understand it.
Ted
RE: Bearing clearance
RE: Bearing clearance
The bearings are new, or used?
The bearing is pressed on to the shaft?
How is the bearing retained in the casing?
RE: Bearing clearance
If not, you can fill up the tolerance zone in one direction and eliminate the excessive clearance necessary for your bearings, but damaging your gearteeths.
If so, there are certain types of bearings which have smaller than average clearances. Or use a different combination of bearings
Greetz Martin
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RE: Bearing clearance
Russell Giuliano
RE: Bearing clearance
There will likely be some Bearing OD to housing clearance. Unless the outer ring is clamped or other precautions are taken that clearance is readily available during a "lift" test if the dial indicator base is grounded to the bearing housing or beyond. Is your "up" test in the radial shaft direction?