Home   |   About Us   |   Career   |   Contact Us
Technical Support
Bearing Storage
Bearing Handling
Bearings are precision parts and, in order to preserve their accuracy and reliability, care must be exercised in their handling.
In particular, bearing cleanliness must be maintained, sharp impacts avoided, and rust prevented.
Bearing Storage
Most rolling bearings are coated with a rust prevent oil before being packed and shipped, and they should be stored at room temperature with a relative humidity of less than 60%.
Installation preparations
When bearings are being installed on shafts or in housings, the bearing rings should never be struck directly with a hammer or a drift, as shown in Fig. 15.1, because damage to the bearing may result. Any force applied to the bearing should always be evenly distributed over the entire bearing ring face. Also, when fitting both rings simultaneously, applying pressure to one ring only, as shown in Fig. 15.2, should be avoided because indentations in the raceway surface may be caused by the rolling elements, or other internal damage may result.
Bearings should be fitted in a clean, dry work area. Especially for small and miniature bearings, a "clean room" should be provided as any contamination particles in the bearing will greatly affect bearing efficiency. All dirt, burrs or metal filings must be removed from the shaft, housing and tools used for mounting the bearings. Shaft and housing fitting surfaces should also be checked for roughness, dimensional and design accuracy, and to ensure that they are within allowable tolerance limits. Bearings should not be unwrapped until just prior to installation. Normally, bearings to be used with grease lubricant can be installed as is, without removing the rust prevent oil. However, for bearings which will use oil lubricant, or in cases where mixing the grease and rust prevent oil would result in loss of lubrication efficiency, the rust prevent oil should be removed by washing with benzene or petroleum solvent and dried before installation. Bearings should also be washed and dried before installation if the package has been damaged or there are other chances that the bearings have been contaminated. Double shielded bearings and sealed bearings should never be washed.
Installing cylindrical bore bearings
For bearings with relatively small interference, the entire circumference of the raceway can be uniformly press-fit at room temperature as shown in Fig. 15.3. Usually, bearings are installed by striking the sleeve with a hammer; however, when installing a large number of bearings, a mechanical or hydraulic press should be used.

When installing non-separable bearings on a shaft and in a housing simultaneously, a pad which distributes the fitting pressure evenly over the inner and outer rings is used as shown in Fig. 15.4. If the fitting is too tight or bearing size is large, a considerable amount of force is required to install the bearing at room temperature. Installation can be facilitated by heating and expanding the inner ring beforehand. The required relative temperature difference between the inner ring and the shaft depends on the amount of interference and the shaft fitting surface diameter.
Fig. 15.3 Fitting sleeve pressure against Fig. 15.4 Fitting sleeve pressure against inner /outer ring simultaneously
» For more information kindly check NTN catalog or Contact Us
  Send Us Enquiry  
  Technical Support  
1. Bearing History
2. Types of Bearings
3. Types of loads
5. Clearance
6. Bearing Tolerance
7. Lubrication
8. Bearing Storage
9. Mounting and Dismounting
10. Bearing Failures
11. Prefix and Suffix Interchange
11. Allowable Speed
  Home | About Us | Products | Downloads | Trade Enquiry | Contact Us | Site Map
  Copyright © 2011 Kay Kay Trading Co. All rights reserved. Created & Developed by Dotcom Service India Pvt. Ltd.