What should we look for when preparing for bearings assembly?

Roller bearings are reliable mechanical components with long service life, provided they are properly installed and maintained.

Proper installation requires expertise and care, cleanliness and accuracy, as well as the right tool. If impurities get into the bearing, then the most efficient seals and the most suitable lubricants do not offer any protection against premature defects in the bearing. However, this can be avoided if we follow some simple rules.

Workplace Requirements

If possible, the assembly must be carried out on a suitable work bench in a dry, dust-free environment. In no case should the bearings be exposed to impurities such as, for example, metal particles, parings, sand or corrosive liquids. Outside, the bearings must be installed only in exceptional cases and taking appropriate protective measures.

When the transport of a complete machine to a suitable workplace is not feasible, it is necessary to bring a bearing or a mechanical part with a bearing to the place where it is possible to carry out assembly of the bearing under suitable conditions.

Preparations for assembly

Apart from the bearing itself, the shaft, housing and other parts of the bearing assembly must be clean. For this purpose, all parts of the bearing assembly, including the seals, must be carefully inspected. Remove any splinters on the parts, clean the shaft bearing and housing and replace the damaged seals. Slightly bend the bearing surface of the bearing on the shaft and in the housing to prevent damage during assembly.

In the case of repairs, the entire machine must be cleaned, especially in the area where the bearing should be mounted

New bearings

The bearings are well protected from corrosion in their original packaging, so remove them from the packaging just before installation. The anti-corrosion agent, which is normally located on the bearing, does not need to be removed, with the exception of the contact surface of the outer and inner ring. Wipe these surfaces with a cloth soaked in petroleum and dry with a clean, lint-free cloth.

Bearings from damaged packaging must be prepared in the same way as used bearings.

Used bearings

These bearings must be carefully cleaned before re-installation. Cleaning the bearings can be cold or hot.

At cold cleaning, the bearing is washed with a brush with petroleum or similar liquid. While rotating, rotate the bearing ring so that all surfaces can be cleaned. Cleaning and final washing must be carried out in separate cleaning containers. During drying, the bearing must be protected against external influences. If you use compressed air for drying, make sure that the bearing does not move. As soon as the bearing is dried, it must be protected against corrosion, for example, with SKF LHPT 48 protective agent.

At hot cleaning, less viscous machine oil is used, heated to about 120°C. For safety purposes, the oil must have a flash point above 250 C. Separate containers must be used for cleaning and final washing. The layer of oil left on the bearing after washing will provide temporary protection against corrosion.

Very dirty bearings are often in such a bad condition that their cleaning does not pay off. In such cases, it is most economical to replace them with new ones. The same applies to sealed bearings that cannot be cleaned and inspected without removing the sealing disc.

CAUTION!
Always wear protective gloves when cleaning. Frequent contact with petroleum products can cause an allergic reaction. In the case of hot oils, fire safety must also be considered.