Key maintenance points for extending the service life of square hole agricultural machinery bearings

The core application scenarios of square hole agricultural machinery bearings are tractors, harvesters, rotary tillers and other agricultural machinery. These equipment operate in harsh conditions such as mud, high load, and frequent start stop for a long time. Proper targeted maintenance can significantly extend the service life of bearings. The core maintenance points are divided into four modules:

🧹 Daily inspection and cleaning maintenance

Square hole wear monitoring: Regularly check the scratches and deformation on the inner wall of the square hole. When the fit clearance exceeds 0.3mm or the crack length exceeds 5mm, replace the bearing or repair the shaft hole in a timely manner.

Seal status check: Confirm that the dust cover and rubber seal ring are not damaged or detached. When the rubber ages, becomes hard, and cracks, replace it with an oil and high temperature resistant seal of the same model.

. Cleaning after homework: Use high-pressure air with a pressure of ≤ 0.6MPa to blow away the sediment and straw debris on the surface of the bearing and inside the square hole. It is forbidden to directly rinse with water to avoid the emulsification failure of lubricating grease.

Long term rust prevention: When the agricultural machinery is idle, apply a thin layer of mineral rust proof oil on the bearing surface, wrap it with plastic film to isolate moisture, and prevent rust on the raceway and mating surface.

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🛢️ Precise lubrication management

Lubricating grease selection and adaptation: Lithium based low-temperature grease with a drop point ≥ 180 ℃ is selected for low-temperature environments; Choose composite lithium base grease containing molybdenum disulfide for high-temperature and dusty environments.

Specification for filling amount: The filling amount of lubricating grease in the bearing chamber is controlled within 1/3~1/2 space, and a thin layer of lubricating grease with a thickness of 0.1~0.2mm is applied to the mating surface between the square hole and the shaft.

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Replacement cycle execution: Replace the lubricating grease after continuous operation for 200-300 hours or quarterly operation. If the grease body turns black, clumps, or mixed with metal powder, replace it immediately and check for bearing damage.

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🔩 Installation and Disassembly Specification

Installation Operation Requirements: Clean the shaft and square hole mating surface to remove burrs, slowly press in with a press or special fixture, prohibit direct hammering with a hammer, and control the fit interference within 0.01~0.03mm.

Coaxiality Verification: After installation, check the coaxiality of the bearing and transmission components, with a deviation of ≤ 0.1mm, adjust the bearing clearance to ensure that there is no jamming or abnormal vibration during operation.

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Disassembly safety operation: Use a puller or hydraulic disassembler to disassemble, soak the rusted parts in WD-40 penetrating oil for 24 hours before operation, and do not forcefully pry them with a pry bar.

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📅 Regular maintenance of agricultural machinery: Strictly follow the maintenance requirements of agricultural machinery shifts, clean up the soil and debris attached to the bearings in a timely manner during work intervals, and regularly lubricate according to the lubrication points specified in the instructions. Heavy load agricultural machinery such as plows and combine harvesters should undergo a comprehensive inspection of the bearing condition after the stage operation is completed, and promptly repair parts with excessive wear to avoid exacerbating bearing wear during faulty operations.