SH basic three-ring reducer common fault disassembly and on-site rapid repair plan

After the equipment is put into long-term use, various types of failures will inevitably occur in the SH basic three-ring reducer due to factors such as load, wear, and aging. Many on-site maintenance personnel are unable to deal with problems such as abnormal noise, oil leakage, excessive temperature rise, and weak output. Blind disassembly only aggravates the failure. This article combines the characteristics of the three-ring transmission structure to sort out common faults, fault causes and maintenance methods that can be directly operated on site, which is full of practicality.

1. Oil leakage from the box, the most frequent basic failure

1. Symptoms of box oil leakage failure: oil leakage and oil dripping from box joints, output shaft/input shaft end, and oil plug position.

2. The main causes of oil leakage in the box: aging and deformation of the gasket, wear and cracking of the oil seal, loose fastening bolts, and excessive oiling.

3. Box oil leakage repair and treatment:

(1) Loose bolts: Tighten the box and end cover bolts evenly and diagonally. Do not apply force on one side to avoid box dislocation and aggravate leakage;

(2) Oil leakage at the shaft end: Disassemble the end cover and replace the skeleton oil seal of the same model. When installing, pay attention to the oil seal lip facing the inside of the box to avoid scratching the lip;

(3) Oil leakage on the joint surface: drain the lubricating oil, disassemble the box, clean the old glue and impurities on the joint surface, replace with a new seal or re-apply oil-resistant sealant and close the box;

(4) The oil level exceeds the standard: drain out excess lubricating oil and adjust the oil level to the standard scale.

2. Abnormal noise and excessive vibration during operation

1. Failure symptoms: There are impact and friction sounds during operation, and the fuselage vibrates obviously. The greater the load, the more serious the abnormal noise will be.

This model has a multi-tooth meshing structure, and there is no sharp noise during normal operation. Abnormal noise is mainly divided into two categories: one is insufficient lubricating oil, and dry friction between the gear and ring plate produces friction noise, which can be alleviated by adding oil; second, internal parts are worn, fasteners are loose, the ring plate is misaligned, and the tooth surface is pitted and peeled off.

2. On-site treatment: If there is slight abnormal noise, first add oil and clean external debris. If the abnormal noise persists, the machine must be shut down, powered off, and disassembled for inspection. Check whether the three ring plates are offset and whether the tooth surfaces are worn. Retighten loose positioning parts. Severely worn ring plates and gears need to be replaced as a whole set. It is prohibited to replace individual parts individually to prevent uneven meshing from causing problems again.

3. Abnormal increase in body temperature

1. Symptoms of abnormal temperature failure: the box becomes hot when running for a short period of time, and the oil temperature is far beyond the normal range.

The inducements focus on three points: long-term overload operation, lubrication failure, and stuck transmission components.

2. Recommendations for maintenance of abnormal temperature: Immediately reduce the load and check the oil quality. Change the oil immediately if the oil deteriorates, water enters, or is mixed with impurities. Check whether the input and output shaft rotation is stuck, and clean foreign matter in the transmission part. If it is overloaded under long-term working conditions, the torque needs to be recalculated to determine whether the reducer needs to be replaced with a larger size.