Stepped shaft, set screw, or collar to locate pillowblock bearings?

[JustTheTibb]

What is the best way to attach a pillowblock bearing to a shaft (obviously including the press fit)? I was thinking a stepped shaft so the bearing can butt up against the step. Alternatively, collars and/or set screws would work, allowing me to get rid of the stress concentration in the stepped shaft. There is purely a radial load for this application. What is typically used in industry, or a better way of doing this?

Thanks for any insight you guys can provide!

 

[caoimhin1]

If its purely radial load, then a stepped shaft is not required...unless you need a definite datum point to locate the bearing relative to the shaft.
Pillow block units usually use either set screws or eccentric locking collars on their inner rings for location. Use the eccentric locking coller if vibration is an issue, otherwise set screws are fine. Some units use tapered adapter sleeves, used when the speed is very high.
Note that an interference fit is not usually necessary or recommended for pillow blocks. h7 tolerance will allow you to slide or lightly tap the bearing into position.

 

[JustTheTibb]

Thank you caoimhin1, much appreciated!

 

[Tmoose]

Is it belt driven?
What rpm?

 

[JustTheTibb]

It will be operating under 1800 rpm and is driven by an electric motor with a gearbox.

 

[Tmoose]

gearbox coupled to this shaft?