Reducer oil leakage is a common fault during equipment operation. It not only causes waste of lubricating oil and environmental pollution, but also causes key components to intensify wear due to poor lubrication, and even cause shutdown accidents. To completely cure the oil leakage problem and avoid repeated repairs, it is necessary to accurately identify the root cause and take targeted measures. The root causes of reducer oil leakage can be mainly attributed to the following four aspects:
1. Internal pressure imbalance ("poor breathing")
Root cause analysis: When the reducer is running, gear meshing friction will generate a large amount of heat, causing the temperature inside the box to rise, the oil to expand, and the internal pressure to increase accordingly. If the breather cap (breather) is blocked by sludge, coal powder, etc., or the design aperture is too small and the internal high-pressure gas cannot be discharged, the lubricating oil will be squeezed out from the gaps with the least resistance (such as oil seals and joint surfaces).
Symptomatic repair of internal pressure imbalance:
Unblock or replace the breather cap: Check and clean the breather cap regularly to ensure that it "breathes" smoothly. For environments prone to clogging, it can be replaced with an oil cup-type breathable cap with a larger hole diameter and less likely to be clogged.
Install a pressure relief device: For reducers operating under high load, consider installing an automatic pressure relief valve to maintain pressure balance inside and outside the system.
2. The sealing system fails (the "line of defense" is damaged)
Root cause analysis: Aging, hardening and cracking of seals (such as oil seals and gaskets) or improper installation are the direct causes of oil leakage. In addition, if there are scratches or burrs on the journal surface where the output shaft contacts the oil seal, or if the output shaft radially beats (eccentric rocking) due to bearing wear, it will accelerate the wear of the oil seal lip and lead to seal failure.
Symptomatic repairs for sealing system failure:
Check and replace seals: Use high-quality oil seals (such as fluororubber) that are resistant to high temperatures and wear. Apply lubricating oil to the lip before assembly, and use special tooling to install it. Brutal force is strictly prohibited to prevent the lip from flanging or scratching.
Repair or replace the damaged journal: If scratches are found on the shaft surface, the smooth shaft surface must be repaired first and then replaced with a new oil seal, otherwise the symptoms will not be addressed.
Replace bearings in pairs: If you can feel obvious gaps when shaking the output shaft by hand, it means that the support bearings are worn. The original bearings must be replaced in pairs to ensure concentricity and eliminate abnormal shaft beating.
3. Improper lubrication management ("blood" abnormality)
Root cause analysis: Excessive refueling is an easily overlooked cause of oil leakage. If the oil level is too high, the gear will violently stir the oil pool during operation, causing the lubricating oil to splash everywhere, accumulate in large amounts at the shaft seal and joint surface, and eventually break through the sealing defense line. In addition, the wrong oil product or failure to change it for a long time will cause the oil to oxidize and reduce its viscosity, which will also increase the risk of leakage.
Symptomatic maintenance of improper lubrication management:
Strictly control the oil level: Add lubricating oil according to the standards in the equipment manual, and ensure that the oil level is between the upper and lower limits of the oil dipstick or oil window.
Regular oil change and cleaning: Replace the new oil of the same brand at the operating temperature of the reducer (warm state), and thoroughly drain the old oil and impurities to keep the oil clean and of appropriate viscosity.
4. Structural and assembly process defects ("skeleton" deformation)
Root cause analysis: The box casting has not been annealed or aged, and will deform after long-term operation; or the inspection hole cover is too thin, causing warping after tightening the bolts, resulting in uneven joint surfaces. During assembly, if the dirt on the joint surface is not cleaned, the sealant is unevenly applied, or the bolts are not tightened in a cross sequence, oil leakage channels will be left.
