three row roller slewing bearing

three row roller slewing bearing needing preload is generally as angular contact ball bearings front bearing use.
triple row roller slewing bearing is generally used in groups, pre tightening in two ways,
1, bearing between the spacer sleeve, the top outer ring, inner ring with pressure pretightening nut.
2, at the end of main shaft side top outer ring, inner ring with a pre tightening nut pressure behind.

Methods 1 septum sleeve ends parallel precision must be very good. Mode 2, pressure ring side of the shaft is vertical to very good accuracy.
On the vertical accuracy requirements of bearing side with the thread of the locking nut is also high.
In addition, bearing must not install anti, anti loaded words bearing will be pressed powder.Note that the pre tension (or preload) must meet the requirements of bearing the instructions, otherwise it will damage the bearing.