Bearing 'Walk'

Pjaynes
(not verified)
Posted in: , on 3. Oct. 2003 - 06:13

we have Lt conveyor pulleys that are experiencing movement of the spherical roller bearings on the adaptor sleeves.(ssn512 Typically)

can anyone offer any advice as to why this may be happening.

Conveyors are relatively small 75&220kw , gravity takeup

VVVF drive control

regards ■

Conveying
Transport
Idlers, Pulleys, Rollers
Parts & Components
Belt Conveyors
Mechanical Conveying
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Re: Bearing 'Walk'

Posted on 3. Oct. 2003 - 08:36

Hi Pjaynes

Normally one pulley bearing is fitted with locating rings, and the opposite one is free to float. This way the pulley is located axially, but with no chance of axial bearing load. If both bearings are inadvertently located with rings, then possibly this could cause the effect that you describe. I assume the adapter sleaves are OK, properly torqued and the shafts are adequately sized?

I also assume that the pulleys are reasonably well aligned and do not endure sidways de-training forces

Regards

LSL Tekpro ■

Graham Spriggs

Re: Bearing 'Walk'

Posted on 3. Oct. 2003 - 08:44

Dear pjaynes

The link below explains the principle of fixed and floating bearings. One bearing must be "fixed" with fixing rings and the other must "float" without fixing rings. It sounds like your problem may be due to both bearings being allowed to float.

http://www.ckit.co.za/Secure/Conveyo...gsBasics.html

Regards,

Gary Blenkhorn ■

Gary Blenkhorn
President - Bulk Handlng Technology Inc.
Email: garyblenkhorn@gmail.com
Linkedin Profile: http://www.linkedin.com/in/gary-blenkhorn-6286954b
Offering Conveyor Design Services, Conveyor Transfer Design Services and SolidWorks Design Services for equipment layouts.

Pjaynes
(not verified)

Re: Bearing 'Walk'

Posted on 6. Oct. 2003 - 01:42

Gary/ Graham

Thanks for your reply

we have locating rings in one housing.

we have taken some measurements on components - seem to be OK.

Torque levels on adaptar sleeves are obtained by setting internal bearing cleances - this was checked on replacements fitted.

Bearing calcs indicate > 60K hrs

shaft deflection estimated 1/1800 - 1/2000



Misalignment - could be a factor. some checks show pulleys

ranging 3- 10mm , off square to belt , on brgs crs of 1530mm

thanks for any other thoughts

regards ■

Re: Bearing 'Walk'

Posted on 8. Oct. 2003 - 04:18

I experienced a similar problem a couple of years back, also on low tension pulleys. As I remember the fault was traced back to incorrect manufacture of the sleeves.

Adi Frittella ■