Generally speaking, SKF bearings will heat up after starting to run, and after a period of time, they will be at a lower temperature (usually 10 to 40 degrees higher than room temperature). The time to normal depends on the bearing size, form, rotation speed, lubrication method, and changes in the heat release conditions around the bearing. At this time, it takes approximately 20 minutes to several hours.
When the bearing temperature has not reached the normal state and abnormal heating occurs, the following reasons can be considered. In addition, the machine should be shut down as soon as possible and necessary countermeasures should be taken.
Causes of temperature rise of rolling bearings
(1) Breakthrough of bearing cooling water.
(2) Degradation of engine oil, oil, or running your own dirty oil, such as oil in water, will cause oil to increase acidity, will reduce oil lubrication, bearing erosion, and cause bearing temperature.
Rolling bearing temperature treatment
When the bearing temperature rises, first determine whether it is faulty. If they really rise, the following treatments should be done:
(1) Check that the pressure, flow rate and piping system of the cooling water are normal. The filtered filter may be blocked and cannot be processed. It can confirm the work when it stops processing, and then put it into use.
(2) The oil pressure of the governor should be checked. The oil pressure may cause the hydraulic valve to close if the water is cooled.
(3) Whether there is a difference, whether there is abnormal sound, check the bearing and the bearing runout test.
(4) Take an oil sample to observe the change in the color of the oil and conduct a test to see if it deteriorates. If it proves to be deteriorated, it should be replaced with new oil and shut down.
(5) Check whether the oil level is normal. If not, check that the water tank drain valve is closed tightly. If closed, oil should be added.
SKF bearing temperature is very important to maintain the proper life of the bearing and prevent the deterioration of the lubricating oil. It is recommended: Try to control it in a non-high temperature state (generally below 100 degrees).Click here for more information about SKF Bearing 2211 EKTN9.
The main reasons for abnormal temperature rise:
Too much or too little lubricant.
The bearing is not properly installed.
The internal clearance of the bearing is too small, or the load is too large.
Excessive friction in the sealing device.
Lubricant does not match.
Creep of the mating surface.
When the SKF bearing temperature is high, the problem should be solved from the following aspects:
1) The amount of oil added is not appropriate, and the lubricating grease is too little or too much. The bearing box should be oiled regularly in accordance with the requirements of the work. High temperature sometimes occurs after the bearing is refueled, mainly due to excessive refueling. At this time, the phenomenon is that the temperature continues to rise, after reaching a certain point (usually about 10℃~15℃ higher than the normal operating temperature) it will remain unchanged, and then it will gradually decrease.
2) The grease added to the bearing does not meet the requirements or is contaminated. The selection of lubricating grease is improper, it is not easy to form a uniform lubricating oil film, can not reduce the friction and wear inside the bearing, the lubrication is insufficient, and the bearing temperature rises. When different types of grease are mixed, a chemical reaction may occur, causing the grease to deteriorate, agglomerate, and reduce the lubricating effect. Contaminated grease will also increase the temperature of the bearing. Dust will fall into the grease during the process of adding grease, causing grease pollution, causing the grease inside the bearing box to deteriorate, destroying the bearing lubrication, and increasing the temperature. Therefore, suitable grease should be selected, the bearing box and bearings should be cleaned during the maintenance, and the fueling pipeline should be checked and dredged. Different types of greases are not allowed to be mixed. If you replace other types of grease, the original grease should be cleaned first; operation and maintenance Add grease regularly, and the grease should be properly kept and moisture-proof and dust-proof.
3) Insufficient cooling. Check whether the pipeline is blocked, whether the inlet oil temperature and return water temperature exceed the standard. If the cooler is not selected properly, the cooling effect is poor and cannot meet the requirements of use, it should be replaced in time or a new cooler should be installed in parallel. The axial flow induced draft fan should also check the insulation and sealing of the core tube.
4) After confirming that there is no such problem, check the coupling alignment and SKF bearings. The alignment of the coupling must conform to the process standard. The thermal expansion of the equipment during operation should also be considered when aligning axial-flow induced draft fans and fluid couplings. Due to thermal expansion on the impeller side of the induced draft fan, the bearing box rises; the temperature rises during the operation of the fluid coupling, and the bearing box expands and the bearing rises. Therefore, the motor should be higher when aligning. Depending on the temperature parameters during operation.