How to prevent bearing contamination
Symptoms:
- ✧ High vibration and wear (caused by denting of the raceways and balls).
Prevention:
- ✧ Always keep your hands, work areas, tools, and fixtures clean.
- ✧ Keep bearings in their original packing until they are ready to be installed, and keep grinding operations away from bearing assembly locations.
- ✧ Seals are essential because faulty or damaged seals cannot protect bearings from foreign contaminants.
How to prevent misalignment
Symptoms:
- ✧ An unusual rise in bearing or housing temperature.
- ✧ Heavy wear in the cage ball-pockets.
Most prevalent causes:
- ✧ Bent shafts.
- ✧ Dirt or burrs on the shoulders of housing or shaft.
- ✧ Shaft threads are not square with shaft seats.
- ✧ Locking nuts with faces that are not square to the thread axis.
Appropriate corrective actions:
- ✧ Perform inspections of shafts and housings for runout of shoulders and bearing seats.
- ✧ Use of ground threads solely on hardened shafts and single point-turned or ground threads on non-hardened shafts.
- ✧ Using lock nuts of the highest precision grade.
How to fix overloaded bearings
Appropriate corrective actions:
- ✧ Reduce the weight that the bearing can handle or redesign it with another bearing with greater load capacity.
- ✧ Add bearings or alter bearing size to relieve pressure on each individual bearing (if high axial or radial loads are the cause of overloading).
- ✧ An angular contact bearing can be optimised for a particular type of load by adjusting the contact angle.
How to cure overheating
Symptoms:
- ✧ Discolouration (from gold to blue) of the balls, rings, and cages.
Causes:
- ✧ Insufficient lubrication or cooling.
- ✧ Inadequate heat paths.
- ✧ Heavy electrical heat load.
Cure:
- ✧ Additional lubricant cooling.
- ✧ Sufficient heat path.
- ✧ Thermal or overload controls.
How to solve normal fatigue failure
Symptoms:
- ✧ Fracture on the running surfaces and the subsequent removal of tiny, discrete particles of material.
Solver:
- ✧ Replace the bearing or re-design it to use a bearing with a longer calculated fatigue life.
How to extend the life of lubricants
Symptoms:
- ✧ Discolouration (blue/brown) of balls and ball tracks.
Lubricant life extension:
- ✧ Correct the improper fit.
- ✧ Control preload better.
- ✧ Cool the shafts and housings down.
How to prevent corrosion
Symptoms:
- ✧ Discolouration (red/brown) of ball areas, bands of balls, raceways, and cages.
Prevention:
- ✧ Diverting corrosive fluids away from bearing areas and, whenever possible, using integrally sealed bearings.
- ✧ The use of external seals in addition to internal seals should be taken into consideration if the environment is hazardous.
- ✧ It is also recommended to use stainless steel bearings.