Rolling bearings, oil-lubricated
Bearing assemblies with rolling bearings lubricated with oil are treated without disassembly and without changing the oil. The purpose is to restore the working surfaces and to protect the bearings against further wear under normal operating conditions.
Procedure for treating bearing assemblies with rolling bearings lubricated with oil using XADO revitalizant compounds
What is treated
- Rolling bearings with a degree of wear of less than 80%, free of defects and mechanical damage (item 9.1).
- Oil-lubricated bearings are treated with the "XADO revitalizant gel for compressors and bearings (industrial)" in 3 stages without changing the oil (item 9.4).
- New bearing assemblies or those with initial wear (up to 10%) are treated by the same procedure, but in 2 stages only (note to item 9.5).
When treatment is not performed
- Rolling bearings with a degree of wear of 80% or more, as well as those having defects and mechanical damage, are not subject to treatment.
Preparation
- Before treating the bearing assembly with XADO revitalizant gel, eliminate oil leaks (item 9.2).
- Before starting the treatment, take measurements of the main performance parameters of the bearings (item 9.3).
- Draw off into a separate vessel a small amount of the in-service oil at a ratio of 1 part of the gel being dissolved to 5-10 parts of oil and heat it to a temperature of 40-60°C.
What is measured before and after
| Parameter | Instrument | How and when |
|---|---|---|
| Radial clearance (radial play) in radial bearings | Stand with a dial indicator, graduation not coarser than 0.01 mm; for bearings with an inner mounting diameter of more than 40 mm a set of feeler gauges No. 1 or No. 2 is permitted | Forced displacement of the shaft in the radial direction towards the indicator stylus placed on the mounting surface of the shaft (or displacement of one of the bearing rings), with the indicator readings recorded. For thrust bearings, axial play is measured instead of radial clearance. Measurements are taken before the start of the treatment and after completion of the full treatment cycle. |
| Axial play of the bearing (maximum axial displacement of one ring relative to the other) | Stand with a dial indicator, graduation not coarser than 0.01 mm | Measured only in radial ball and spherical bearings; forced axial displacement of the shaft or of the bearing race towards the indicator stylus and reading of the indicator. |
| Radial and/or face runout of the bearing assembly shaft | Indicator stand with a measuring dial indicator, graduation not coarser than 0.01 mm | Rotation of the unloaded shaft with the indicator stylus set on its radial and/or face surface and reading of the indicator. |
| Vibration level of the bearing or of the bearing assembly (vibration acceleration, vibration velocity, vibration displacement) | Vibrometers of various types | At fixed points of the bearing assembly housing in the vertical, horizontal and axial direction of each bearing support. |
| Noise level of the running bearing assembly under a fixed load | Sound level meters of various types | At specified locations at a fixed distance from the source of maximum noise, with no extraneous noise sources present. |
| Operating oil temperature | Liquid-in-glass thermometer or non-contact pyrometer | After a fixed running time of the bearing assembly under a specified load at the same ambient temperature. |
| Current consumption or power consumption of the electric motor | Electricity meters, clamp meters, wattmeter or a multimeter for determining electrical parameters | For bearing assemblies of electrically driven units; at no load or under a fixed load. |
Dosage rates
| Compound | Rate | How and when |
|---|---|---|
| XADO revitalizant gel for compressors and bearings (industrial) | 1.2 ml per 1 litre of in-service oil | Per 1 treatment stage; 3 stages in total without changing the oil (for new assemblies and assemblies with wear up to 10% — 2 stages). |
| In-service oil for dissolving the gel | 1 part of the gel being dissolved to 5-10 parts of oil | The oil is heated to a temperature of 40-60°C, the components are thoroughly mixed. |
Treatment stages
- Pour a small amount of the in-service oil (1 part of gel to 5-10 parts of oil), heated to 40-60°C, into a separate vessel, add the calculated amount of the "XADO revitalizant gel for compressors and bearings (industrial)" at a rate of 1.2 ml per 1 litre of in-service oil, and mix thoroughly. Introduce the resulting mixture into the oil bath of the bearing assembly, start the mechanism and operate it in the normal mode.Interval before the next stage — not less than 8-12 hours of total bearing running time
- Carry out in the same way as the first stage: prepare the mixture of the gel with the in-service oil at the same dosage and introduce it into the oil bath of the bearing assembly, operate the mechanism in the normal mode.Interval before the next stage — not less than 8-12 hours of total bearing running time
- Carry out in the same way as the first stage: prepare the mixture of the gel with the in-service oil at the same dosage and introduce it into the oil bath of the bearing assembly, operate the mechanism in the normal mode. For new bearing assemblies and assemblies with initial wear (up to 10%) the third stage is not performed — the treatment is carried out in 2 stages.The treatment is deemed complete after 350 hours of total bearing running time from the beginning of the first stage
After treatment
- After completion of the full treatment cycle, repeat the measurements of the main performance parameters of the bearings in accordance with item 9.3: radial clearance (axial play for thrust bearings), axial play, radial and/or face runout of the shaft, vibration level, noise level, operating oil temperature, current or power consumption of the electric motor — in order to determine the effectiveness of the application of the XADO compounds.
Points to watch
- The treatment is carried out without changing the oil.
- The interval between stages — not less than 8-12 hours of total bearing running time.
- Oil leaks must be eliminated before the treatment begins.
Compounds for these units
- Revitalizant gel for compressors and bearingsPiston, screw and centrifugal compressors; rolling and sliding bearings running in an oil bath; machine-tool spindle units and slideways.
Source: Instructions for the use of XADO revitalizant gels IE-24.6-25612000-005-2008, pages 17–18.