Bearing life is short? Increased service life of motor bearings
When the bearing selection is selected, the safety margin is reserved. After the batch is put on the market, many motors still have problems due to bearing problems. Ms. See the inspection records provided by Xiao S in detail, and found that it is mostly caused by dry grinding of bearings caused by lack of oil. Further verification of the tracking record reveals that the grease does not meet the requirements.
The above events reflect that the service life of the motor bearing is far more than just a sufficient margin for the selection. At least the lubrication problem is an important constraint. In addition, improper assembly, poor sealing and overload fatigue are also the main causes of premature bearing damage, and the actual service life of the bearing is thus shortened. Bearing life is the key to ensure long-term safe operation of the stator and rotor in the effective part of the motor.
About bearing life
Rolling bearing life
In general, the metal fatigue of the rolling contact surface is the main cause of damage to the rolling bearing. The life of the rolling bearing is defined by the number of revolutions (or the number of working hours at a certain number of revolutions), and the bearing within this life is not in any of its bearing rings or rolling. Initial fatigue damage (flaking or missing).
Because the same bearing under the same working conditions, the actual life is not the same, so the "rolling bearing life" is more precisely defined as: a sufficient number of groups of the same bearing under rated load 90% of the bearing should reach or exceed the life value.
Calculated life
The number of revolutions or hours calculated using the life formula based on load and revolution.
Actual life
Refers to the actual life that can be achieved before the bearing is damaged. Because the bearing damage is usually not caused by fatigue, it may be caused by factors such as incorrect selection, poor lubrication, pollution, improper installation.
Extend bearing life
Installation and disassembly
1) Use mechanical, hydraulic or heating methods for proper and efficient bearing assembly.
2) The use of a full range of tools and equipment for a variety of specialized engineering services technologies makes these tools simple, fast and more efficient.
3) Apply special tools and techniques for professional assembly to maximize machine uptime.
lubricating
Although a variety of “maintenance-free” sealed bearings can be installed, 35-36% of the premature failure bearings are due to improper technical application and improper use of the grease. Any improperly lubricated bearings will inevitably fail prematurely before the normal service life.
Since bearings are usually the least accessible parts of mechanical equipment, problems can arise if they are not lubricated frequently. In the event that manual maintenance is not possible, a fully automatic lubrication system is developed to achieve optimum lubrication. As long as high-quality grease, tools and techniques are used for effective lubrication as required, it will help to significantly reduce downtime.
Pollution prevention
Bearings are precision parts and will not operate effectively if the bearings and grease are contaminated. In addition, since maintenance-free sealed bearings that have been greased only occupy a small portion of all used bearings, at least about 15% of all prematurely failed bearings are due to contamination problems.
Fatigue prevention
● Prevent the machine from being overloaded, improperly used or maintained, and the bearings will be affected, resulting in premature bearing failure.
● Use state monitoring equipment for inspection and analysis. When the bearing is under improper maintenance or excessive stress, it will issue an “early warning” to avoid sudden or unplanned failure.
