In order to ensure correct adjustment, the tapered bearings are required to have “zero end play” at all times. The procedure to accomplish this in a caster is as follows:
- Check that each spacer is positioned in the correct place, through the seal and up against the face of each bearing.
- Install the wheel into the rig.
- Install the axel through the legs, spacers and bearings.
- Assemble the slotted nut on the end of the axle and tighten with a wrench until the wheel has sufficient drag to stop the wheel from rotating at all when released from your hand while trying to spin the wheel. This will seat the tapered bearing cones into the cups.
- Back the nut off approximately a quarter of a turn to locate the cross drilled hole in the axle and one of the slots in the nut.*
- Spin the wheel. When released from your hand, the wheel should turn approximately one half of a rotation.
- Install the roll pin.*
The bearings should be checked for the correct adjustment and to assure they are properly lubricated every 500 hours of service or as frequently as possible afterward.
*Some casters may be assembled with a Flexloc nut. This product has a locking feature that allows infinite adjustment without using a roll pin to secure the nut.
Tapered Roller Bearing Installation
- Install the cup(3) into the wheel bore. The cup (3) must be fully seated against the step in the bore. Make sure the taper of the cup (3) is in the proper orientation.
- Install the cone (2) into the cup (3). This is a loose fit.
- Install the flinger washer (7) on top of the cone (2).
- Install the closure (5) over the flinger washer (7). Make sure to fully seat the closure (5) around flinger washer (7) and cup (3).
- Repeat above procedure for the opposite side.
- Install the wheel (10) into the caster.
- Place a spacer (6) between the closure (5) and the caster leg on each side.
- Slide the axle (9) through the caster legs and wheel assembly (10).
- Install a castle nut (8) and tighten until the wheel (10) will not spin. This will seat the bearings into the bore.
- Loosen the castle nut (8) until the wheel (10) is free spinning.
- Tighten the castle nut (8) until the wheel (10) begins to drag.
- Align the slots in the castle nut (8) with the cross holes in the axle (9) by tightening or loosening the castle nut (8). If tightening, the wheel (10) must be able to spin somewhat freely. If loosening, the wheel (10) cannot have any end play. The bearing should have some pre-load. Install cotter pin or roll pin (4) through the slotted nut (8) and axle (9).
- Lubricate bearings through the grease zerk (1) using Shell Alvania Grease 2 or equivalent.
