Time：2020.07.10 Source：Roller Bearings Suppliers
Bearings require unscheduled maintenance and maintenance during use. Even so, some failures will occur during the use of bearings. We better repair the use of bearings. Wuxi Spark Bearing Co., Ltd. analyzes spherical rollers in detail When the bearing fails, how can we find the real fault, the elimination method is the best solution.
Spherical roller bearing in the head of the air compressor and troubleshooting
1. Check whether the connecting rod bushing, connecting rod bushing, main shaft spherical roller bearings are worn, strained or burned, whether the connecting rod bolts are loose, and check whether the main oil passage of the air compressor is clear; it is recommended to replace the severe wear or strain Bearings, bushings, main bearing, tighten the connecting rod bolts (torque specification 35-40N.m), use the compressed air hole to align the air compressor oil inlet; air dredge the main oil passage. When reassembling, attention should be paid to the spindle bearings.
2. Check whether the grooves of the main and forced pulleys are common. If they are not common, please replace them, and adjust the belt tightness (press the belt with your thumb, the interval between the belts should be 10 mm).
3. Check the lubricating oil inlet pressure and whether the oil pipeline is damaged or clogged. If the pressure is lacking, you should adjust, arrange and replace the failed pipeline; check the oil quality and impurity content of the lubricating oil. Compare with the operating specifications. ; Check if the air compressor is supplied with oil. If there is no oil supply, a full inspection should be conducted immediately.
4. Check whether the bolts of the spherical roller bearing fixed by the air compressor are loose and tightened.
5. The gear-driven air compressor should also check whether the gear is loose or the cooperation of the gear device and the cooperation of the spherical roller bearing gap. If the nut is loose, tighten the nut. If there is any problem with the cooperation, it should be replaced. Need WSBC 21318 E, click here.
Judgement of the accuracy and performance of the installation of spherical roller bearings
The correct installation of the spherical roller bearing directly affects the accuracy, life and performance of the bearing when it is used.
(1) When cleaning a large number of spherical roller bearings, first use hot engine oil with a temperature of 90 to 100°C to drench the package oil, and at the same time use a seamless and non-chip tool to dig out all the old oil and then drench it After a few minutes, rinse the engine oil with kerosene, and finally clean it with gasoline again. After cleaning and cleaning, wear film gloves and place the spherical roller bearings on a clean cloth or paper on the table to dry.
(2) Prior to the installation of spherical roller bearings, the processing quality of shafts and seat holes and related parts (such as dimensional accuracy, shape accuracy and surface roughness, etc.) should be checked with appropriate measurement tools according to the technical requirements on the design drawings. ).
(3) Open the spherical roller bearing package immediately before installation, immerse it in the above-mentioned gasoline and other liquids, and turn it slowly by hand. Make sure that the cage, rolling elements and the package oil on the surface of the raceway are thoroughly cleaned.
(4) The assembly surface should be cleaned with clean gasoline, kerosene, toluene or xylene solutions, and dried with a clean rag, and then coated with a thin layer of lubricating oil, so that the installation operation is more convenient.
(5) Note that spherical roller bearings with seals cannot be cleaned by this method, and the inside of the seals should be kept as they are and cannot be cleaned.
(6) If there are bruises, burrs, rust spots or solid particles (such as abrasive debris, sand, mud) on the assembly surface of the shaft and bearing housing holes, it will not only make the installation of the spherical roller bearing difficult and make the installation position not It is correct, and solid particles will be abrasive if they fall into the bearing. When the spherical roller bearing rotates, it will abrade or scratch the working surface of the bearing, so it must be carefully checked before installation. If the above defects are found Should be amended. For example, use an oil file to remove burrs, bumps, rust spots, and polish with a fine emery cloth, such as cleaning solid particles and dirt. Need WSBC 21316 E, click here to learn more.
Spherical roller bearing installation failure detection method
After the bearing installation is completed, in order to check whether the installation is correct, a running inspection is required. Small machinery can be rotated by hand to confirm whether it rotates smoothly. The inspection items include poor operation due to foreign objects, scratches, and indentations, unstable torque due to poor installation, poor processing of the mounting seat, excessive torque due to too small clearance, installation errors, and seal friction, etc. Wait. If there is no abnormality, power operation can be started.
The power operation starts from the no-load low speed and gradually increases to the rated operation under the specified conditions. The items to be checked during the trial operation are abnormal sound, temperature change of the spherical roller bearing, leakage or discoloration of lubricant, etc. If an abnormality is found, the operation should be stopped immediately, the machine should be inspected, and the bearing should be removed for inspection if necessary.
1. The installation and adjustment of low-noise spherical roller bearings can also imitate the grouping method of long-life bearings, so that the size of the interference fit is more consistent, and the bearing clearance is also more consistent. I hope that the interference fit can be compared within the possible range A small value ensures that the deformation of the bearing raceway is small, so that the noise caused by the passing of the rolling element becomes small.
2. The clearance has a great relationship with noise. The ideal state is when the spherical roller bearing is in the highest temperature state of operation, the clearance value is just zero. The methods for judging the excessive clearance are: the axial displacement of the spherical roller bearing in a static state, the reciprocating amplitude is large, and a large and heavy turbid noise is emitted during operation.
3. If an unpleasant sharp howling noise is emitted during operation, it means that the preload of the spherical roller bearing is too large and the bearing has a large pre-interference, and the preload should be slightly relaxed. If the clearance is too large, the two bearing rings can be slightly offset in the axial direction: both reducing the clearance and increasing the axial rigidity can reduce the bearing noise.
4. When the rolling body enters the no-load zone, it will slip or move left and right, which will increase the noise and cause wear, and the small clearance and large axial stiffness can eliminate this phenomenon. But the clearance should not be too small, so as not to cause excessive temperature and shortened life.
5. Sometimes due to the large operating temperature range of the main machine, or the large dispersion of the size of the shaft and the bearing seat hole, it is impossible to obtain a more appropriate clearance in one adjustment. In this case, the outer diameter of the spherical roller bearing can be adjusted. The ring adopts elastic constant pressure preloading method.