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Mounting instructions for Extreme Bearings

Mounting an Extreme Bearing step by step

Part name

  1. Housing
  2. Cover
  3. Cover seal
  4. Back seal
  5. Bearing
  6. Adapter sleeve
  7. Locating ring
  8. Oring
  9. Bolts
  10. Grease nipple

  1. Put some grease on the seal lip.
  2. Position both bearing units onto the shaft and bolt the bearing housing to the machine frame but do not tighten the bolts all the way yet.
  3. Check if the shaft has the correct level on the machine frame.
  4. Tighten the attachment bolts of the housing to the frame.
  5. Start the clamping procedure on the drive (fixed) side, never on both sides at the same time!
  6. Method 1: As shown in the diagram (fig. 1), position the outer edge of the bearing race exactly level with the outer edge of the bearing housing to maintain inner bearing clearance after tightening the bearing adapter sleeve.
Put some grease on the locking nut.

Method 2:

In case you want highly accurate axial positioning on the shaft, position only the bearing on the fixed side in the casing. As shown in figure 2, the position of the outer edge of the bearing race is not exactly level with the outer edge of the bearing housing after tightening the bearing adapter sleeve. This difference is indicated by A in figure 2 and the table shows the recommended values for A in mm depending on the diameter of the shaft.

7. The locking mechanism for the bearing is based on an adapter sleeve. First put some grease on the locking nut, both on the thread and the front surface.

8. Lift the shaft a little so that the bearing is free from load and the adapter sleeve can move freely.
9. Place the locating ring in position and then screw on the locking nut with its chamfer side facing the bearing. Before starting the final tightening procedure, the bearing should be pushed up onto the tapered seat until the bearing inner ring cannot be rotated relative to the shaft. Then turn the nut through the tightening angle as given in the table for spherical roller bearings. The bearing will be displaced axially (inwards) on the tapered seat during tightening. The residual clearance of the roller bearing should be checked if possible.

Place a spanner wrench in the groove in the locking nut and use it to tighten the bearing onto the shaft. Tightening angles are given in the table

Put some grease on the locking nut.

12. Make sure that the O-ring is mounted properly.

13. Check that the shaft is not too long in case you want to use a closed blue cover seal. If you have a bearing for a drive situation, use an open cover with a shaft seal. In that case, put some grease on the seal lip and carefully push the seal over the shaft.

14. When you have chosen Method 1 at step 6 in the instructions, the shaft with the bearing shall have about one millimetre clearance backwards by mounting on the fixed side. In case your construction demands Method 2 with highly accurate axial positioning, check the position. If there is too much displacement, undo steps 6-14, correct the position and repeat the steps again.

15. Tighten the cover with the attachment bolts.

16. The last step is to fill up the bearings with grease. Slowly pump the grease into the bearing unit while rotating it by hand and stop pumping as soon as you notice that no air is gradually passing the seals. If you pump too fast, the trapped air will push the excess grease out of the bearing before it is full.

Important information for initial greasing if it is a pressure-tight bearing unit

In some configurations, the bearing units from Extreme Bearing are pressure-tight. Therefore it is necessary to keep the cover a little bit open while you do the initial greasing. Otherwise problems like in the picture shown here can occur.
In addition, whenever it is necessary to add some more grease later, you should always take care not to create over pressure in the housing. The Extreme Bearing units are pressure-tight when used with the following configurations of seals: AS/AS, AS/VK, CL/CL and CL/VK.
Please inform your maintenance crew about this special service operating instruction. After filling with grease, it could be helpful to take away the grease nipples completely and exchange them with a standard stainless steel bolt, so it will be impossible to make mistakes.