1. Oil leakage from the box
This is one of the most common faults of the ZQ reducer. Oil leakage in the box is usually caused by the following reasons:
(1) Sealing failure of the joint surface of the box: If the end covers or joint surfaces of the box are uneven, the bolts are loose, or the dirt on the joint surface is not completely removed during maintenance, or the sealant is improperly applied, it will cause lubricating oil to seep out from the gaps.
(2) The blockage of the vent hole causes the internal pressure to increase: When the reducer is running, the gear friction and heat will increase the temperature inside the machine. If the ventilation hole (breathable cap) is unreasonably designed or blocked by dust or oil, the pressure inside the box will gradually increase, and the lubricating oil will be squeezed out from the gaps in the box under the action of the pressure difference.
(3) Overfilling of lubricating oil: If the amount of lubricating oil exceeds the upper limit, the oil pool will be violently stirred during operation, and a large amount of lubricating oil will splash and accumulate on the shaft seal, joint surface, etc. of the box, which can easily cause leakage.
(4) Box casting defects: The box is usually cast from gray cast iron or ductile iron. If there are process defects such as pores, shrinkage holes, slag inclusions or cracks during the manufacturing process, oil leakage from the box will easily occur after long-term use.
2. Box rupture and deformation
(1) Box cracking: Long-term overload operation, frequent impact loads, vibration fatigue caused by shaft misalignment, and uneven bolt pre-tightening force during installation may cause box cracking. In addition, bumps during transportation or long-term material fatigue are also causes of cracking.
(2) Box deformation: When the reducer is under heavy load, or the casting is not annealed/aging during manufacturing and the internal stress is not eliminated, the box may be deformed. Deformation will cause poor meshing of the internal gears, causing oil leakage, abnormal noise and vibration in the box.
3. Other box-related faults
(1) Bearing chamber wear: The bearing box of the reducer housing or the bearing chamber in the inner hole of the box may wear during long-term operation, affecting the support and positioning of the bearings.
(2) Surface coating problems: If the coating process on the surface of the box is not strictly controlled or the surface is improperly treated before painting, it may cause corrosion and wear problems on the box.
Routine responses and preventive measures for the above failures:
(1) For oil leakage: Check and clean the vent cover regularly to ensure the balance of internal and external air pressure; strictly control the amount of oil to the center line or the specified scale; tighten the box bolts, remove old glue and re-apply sealant evenly; if the seals are aging, they need to be replaced in time.
(2) Regarding cracking and deformation: If minor cracks are found, you can use polymer composite materials to repair them or find professionals to weld and repair them; if the oil leakage is serious and it belongs to a key material line, it is recommended to directly replace it with a new reducer with a more stable structure. Overloading and frequent impact loads should be avoided in daily operation, and the anchor bolts and connectors should be tightened and stressed evenly during installation.
