What should be noted when replacing the oil seal of WB micro cycloidal reducer

The core of replacing the oil seal of WB micro cycloidal reducer is to prevent shaft/seat damage, correct direction, vertical press fit, proper lubrication, journal repair, and static leakage test. The following are the key precautions for disassembling the entire process:

1、 Shutdown and safety preparation (prerequisite)

Completely cut off power, stop the machine, hang a warning sign, and wait for the gearbox to cool down completely (to avoid burns and oil splashes)

Drain the lubricating oil from the gearbox (open the drain plug) to prevent oil leakage and pollution during disassembly, which may affect operation

Dismantle the coupling/pulley and protective cover, mark the components properly to avoid installation errors; Protect the shaft extension end to prevent collision and scratches

2、 Dismantling of old oil seal: It is strictly prohibited to damage the shaft neck and seat hole

Tool: Prioritize using a specialized oil seal puller; When there are no tools, use a flat screwdriver wrapped in soft cloth/copper skin to evenly pry the outer edge of the oil seal. It is strictly forbidden to pry or directly poke the lip at a single point, and it is absolutely forbidden to scratch the shaft neck, inner wall of the seat hole, and sealing surface of the cycloidal disk/needle gear housing

Observing old oil seals: Record lip orientation, wear/aging/spring detachment, and determine the root cause of oil leakage (shaft wear, vibration, installation tilt, poor lubrication)

Cleaning: After removal, use isopropanol/acetone+dust-free cloth to thoroughly clean the seat hole groove and shaft neck, remove old glue, oil sludge, metal shavings, and burrs; The steps and chamfers inside the seat hole must be smooth and undamaged

3、 New oil seal selection and pretreatment (core matching)

1. Strict specification matching: Select double lip skeleton oil seals (TC type commonly used for WB microcomputers) with the same inner diameter, outer diameter, thickness, skeleton material, and lip material (nitrile/fluorine rubber) according to the WB model, and do not mix sizes

2. Appearance inspection: The new oil seal is free of damage, deformation, cracks, and missing glue; Smooth lips without burrs, springs without detachment/distortion, and skeleton without rust

3. Lubrication pretreatment (preventing lip curling and tearing):

(1) Thin coat the inner side of the lip (main lip) with the same type of gearbox lubricating oil/lithium based grease, and it is strictly prohibited to use lubricating grease containing solid particles

(2) Apply a thin layer of lubricating grease/a small amount of anaerobic adhesive (to prevent loosening and assist in pressure insertion) on the outer ring of the oil seal (mating surface with the seat hole)

(3) Apply oil evenly on the surface of the shaft neck (oil seal sliding area) to reduce installation friction

4. Neck repair: WB microcomputer shaft is thin and prone to wear

(1) Minor scratches (<0.05mm): Use 800-1000 grit fine sandpaper to lightly polish along the circumference, and then polish until Ra ≤ 0.8 μ m

(2) Wear groove/depth>0.1mm: It must be repaired with a shaft sleeve, electric brush plating, or laser cladding, otherwise the new oil seal will still leak oil quickly

(3) The shaft neck has key slots/steps: a guide sleeve/plastic sleeve is used to prevent the lip from being cut by sharp corners