Wholesale planetary gearbox speed reducer with reliable performance motor

1) Pressure difference between inside and outside the reducer.

During the operation of the reducer, the friction and heat of the kinematic pair and the influence of the ambient temperature increase the temperature of the reducer. If there are no air holes or air holes blocked, the internal pressure of the reducer will gradually increase. The higher the internal temperature, the greater the pressure difference with the outside world, and the lubricating oil will leak out from the gap under the pressure difference.

2) The structure design of reducer is unreasonable.

A, inspection hole cover plate is too thin, easy to produce deformation after tightening bolts, making the joint surface uneven, and leaking oil from the contact gap;

B, During the manufacturing process of the reducer, the casting is not annealed or aged, and the internal stress is not eliminated, which will inevitably lead to deformation, clearance and leakage;

C, there is no oil return groove on the box body, lubricating oil accumulates in the place such as shaft seal, end cover and joint surface, and leaks out from the gap under the action of pressure difference;

4) The structure design of shaft seal is unreasonable. In the early stage, the reducer used oil groove and felt ring shaft seal structure. During assembly, the felt was compressed and deformed, and the joint gap was sealed. If the contact between the journal and the seal is not ideal, the seal will fail in a short time because of the poor compensation performance of felt. Although there are oil return holes in the oil groove, it is easy to block and the oil return function is difficult to play.

3), too much oil.

During the operation of the reducer, the oil pool is stirred badly, and lubricating oil splashes everywhere in the reducer. If too much oil is added, a large amount of lubricating oil will accumulate in the shaft seal and joint surface, resulting in leakage.

4) Improper maintenance technology

During equipment maintenance, oil leakage may also be caused by incomplete removal of dirt on the joint surface, improper selection of sealant, reverse installation of the sealing element, and failure to replace the sealing element in time.

4. How to control oil leakage of reducer?

1) Improve the ventilation cap and inspection hole cover plate.

One of the main reasons for oil leakage is that the internal pressure of the reducer is greater than the external atmospheric pressure. If the internal and external pressures of the reducer are balanced, oil leakage can be prevented. Although all reducers have ventilation caps, the ventilation holes are too small to be blocked by pulverized coal and oil. Moreover, the cover plate of the inspection hole should be opened every time you refuel, and once you open it, the possibility of oil leakage will increase, so that the places that did not leak will also leak. For this reason, an oil cup type venting cap was made, and the original thin inspection hole cover plate was changed to 6mm thick. The oil cup type venting cap was welded on the cover plate, and the diameter of the venting hole was 6mm, which was convenient for ventilation and achieved pressure equalization. In addition, the oil was filled from the oil cup without opening the inspection hole cover plate, which reduced the chance of oil leakage.

2) Smooth flow

In order to prevent the excess lubricating oil thrown by the gear on the bearing from accumulating at the shaft seal, the excess lubricating oil must flow into the oil return pool in a certain direction, that is, it can flow smoothly. The specific method is to open an oil return groove inclined to the machine in the center of the lower tile of the bearing seat, and at the same time, open a gap at the straight mouth of the end cover, which is opposite to the oil return groove, so that the excess lubricating oil flows into the oil return pool through the gap and the oil return groove.

3) Improve the shaft seal structure.

1) Improvement of shaft seal of reducer with half-shaft output shaft: the output shaft of reducer of most equipment such as belt conveyor, screw unloader and impeller coal feeder is half-shaft, which is convenient for modification. Disassemble the reducer, remove the coupling, take out the shaft seal end cover of the reducer, machine the groove on the outer side of the original end cover according to the matching frame oil seal size, and install the frame oil seal, with the spring side facing inward. During reassembly, if the end cover is more than 35mm away from the inner end face of the coupling, a spare oil seal can be installed on the shaft outside the end cover. Once the oil seal fails, the damaged oil seal can be taken out and pushed into the end cover, thus saving time-consuming and laborious procedures such as disassembling the reducer and disassembling the coupling.

2) Improvement of shaft seal of reducer with full shaft output: the reducer with full shaft transmission has no coupling, and if it is reformed according to the scheme of 2.3.1, the workload is too large and it is unrealistic. In order to reduce the workload and simplify the installation procedure, a detachable end cover is designed, and an open oil seal is tried. Machine the groove on the outer side of the detachable end cover. When installing the oil seal, take out the spring first, cut the oil seal into an opening shape, wrap the oil on the shaft from the opening, butt the opening with adhesive, and then install the spring and push it into the end cover.

4) Adopt new sealing materials.

For the leakage of the static sealing point of the reducer, a new polymer repair material can be used to stick it up. If the oil leakage at the static sealing point of the reducer is in operation, it can be plugged with the surface engineering technology emergency repair agent Viscous-Polymer 25551 and 90T composite repair material, so as to eliminate the oil leakage.

5), seriously implement the maintenance process.

When the reducer is overhauled, the technical procedures should be carefully implemented. The oil seal should not be installed upside down, the lip should not be damaged, the outer edge should not be deformed, the spring should not fall off, the joint surface should be cleaned, the sealant should be evenly applied, and the oil filling amount should not exceed the scale of the oil gauge.

6), wipe

Through treatment, the static sealing point of reducer can generally achieve no leakage. However, due to aging seals, poor quality, improper assembly and high surface roughness of shaft, some dynamic sealing points still have slight leakage. Because of poor working environment, coal dust sticks to the shaft and appears oily, so it is necessary to wipe the oil on the shaft after the equipment stops running.