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.

The inner ring and shaft coordination

With the inner ring and the shaft, with no interference, no clearance of the state as the target (Line to Line). With the outer ring and the outer shell is movably matched with the hole.
Used in the same inner diameter of the casing in parallel with the double row spherical roller bearing case, outside diameter tolerance is F6, so as to be movable fit.
thrust ball bearing screw support frame for angular contact ball bearing ,as the shaft size tolerances recommended H5 as shell hole size tolerance, recommendation H6
The clearance and preload bearings
Install bearings, applying pre load appropriate to give, as the axial clearance, the regulations are as follows.

Spindle bearing and running

The running purpose is to make the bearing in the formal angle before, the roller and raceway contact through running, can have good conditions, to maintain the bearing contact with good accuracy, and avoid the damage of the bearing roller in the beginning due to high-speed and heavy haul when in use and the raceway, thereby improving the bearing  life and accuracy .
Because the cross roller bearings is not completely rolling contact, between the shoulder and the inner roller end the existence of sliding contact, if the condition is not good, it is easy to appear the phenomenon of occlusal damage, so more attention should be paid to this kind of bearing running.
The precision spindle bearing is the main shaft bearing of precision machine tools and similar equipment, to ensure the accuracy of its work and the use of performance of precision machine tool.