1. There are bumps on the gear tooth surface causing noise
Situation: This problem is mainly reflected in the test bed of the assembly plant of the complete machine manufacturer. The characteristics of this kind of abnormal sound: the sound frequency is stable, there is abnormal sound in one direction, and there is no abnormal sound in reverse rotation. The speed and abnormal sound of the low-speed shaft can be calculated The frequency relationship of the noise is used to determine the specific location of the abnormal noise.
Reason: bumps occurred during the assembly process. Due to the company's flaws in the quality control of the test, a very small number of gearboxes may have such problems.
Treatment: According to the analysis results, carefully look for the bumps on the tooth surface of the relevant gear. When searching, wipe off the oil on the tooth surface to avoid affecting the feel. Bruises mainly exist on the tooth top and both sides of the tooth profile.
2.Abnormal noise caused by excessive pitch error of the gear itself
Situation: This problem is also reflected in the assembly plant of the complete machine manufacturer. The characteristics of this kind of abnormal sound: the sound frequency is stable, and the two-way rotation is abnormal.
Reason: abnormal noise caused by excessive changes in adjacent tooth pitches caused by gear processing. The gear test report of the problem gear can be found through the speed ratio relationship.
Treatment: Except for the removable high-speed shaft, it cannot be handled on site, and can only be returned to the company for replacement and repair.
3. Abnormal noise caused by friction interference
Situation: The problem is more likely to occur in the repair shop, the turning is not moving or the turning is difficult, and there is a friction sound during the test drive. The reason for the appearance of the wind field is generally the interference of the oil slinger and the end cover, accompanied by abnormal heating of the relevant parts.
Treatment: find out the parts that interfere with friction, rework or tighten the parts.
4. Abnormal noise caused by the bearing's own problems
Situation: When the sound is humming and the frequency is fast, the tooth surface inspection is normal, and the speed ratio relationship is used to calculate that it is not a gear problem, then it is most likely that the bearing has a problem.
Reason: There are dents on the inner ring raceway or roller surface of the bearing, which will cause the bearing to run unsteadily and cause abnormal noise.
Treatment: Check the bearing raceway and roller carefully, and replace the bearing if there is a problem.
5. Abnormal noise caused by long-term gear parking and corrosion
Situation: One tooth on each of the two gears of a pair of gear pairs showed long strip-shaped rust marks, and the remaining teeth were intact.
Reason: Long-term parking of the gearbox causes rust on the tooth surface and abnormal noise due to unstable operation.
Treatment: The rust can not be completely eliminated, it can only be polished with oilstone first, and then follow-up.
6. Abnormal noise not caused by the gearbox itself
Situation: The noise occurs near the low-speed end spindle or the high-speed end brake disc. After checking that the gearbox components are intact, there are still abnormal noises, or the noise frequency is not proportional to the speed.
Reason: The low-speed end may be a problem with the hub or spindle bearing, and the high-speed end may be caused by the alignment deviation of the coupling or the motor.
Treatment:After repeatedly searching the gearbox and confirming that there is no problem with the gearbox, it can be judged that there is a problem with other parts, and the manufacturer of the whole machine can be asked to search for the parts that may have problems.