How to troubleshoot the source of abnormal noise in the TPA315-40-1 worm gear reducer

To investigate the source of abnormal noise of the TPA315-40-1 worm gear reducer, you need to follow the principle of 'first external then internal, first static then dynamic, first simple then complex', and locate the fault point through step-by-step detection. The specific operations are as follows:

Step 1: External static inspection (stop and power off, no disassembly)

1. Inspection of connecting parts

Remove the coupling protective cover and check whether the elastomer/pin is aged, broken or fallen off, and whether the coupling bolts are loose or slippery; shake the coupling by hand. If the radial movement is >0.05mm, it means the fit is loose or the coaxiality is out of tolerance.

Check the tightening status of the anchor bolts, and retest the torque with a torque wrench (according to the requirements of the equipment manual, for example, the torque of M20 bolts is about 280-320N·m); observe whether the base gasket has collapsed and whether there are cracks in the foundation. If there are signs of resonance, it is most likely that the foundation stiffness is insufficient or the bolts are loose, causing abnormal noise.

2. Inspection of seals and accessory components

Check whether the end cover oil seal and the joint surface of the box body are leaking, and whether the oil seal lip is worn and flanged; turn the shaft end of the oil seal by hand. If there is a 'squeaking' friction sound, it means that the oil seal is too tight or is worn, causing abnormal noise.

Check whether the breathable cap is clogged. If clogged, the pressure inside the tank will rise, causing splashing of lubricating oil and local vibration and abnormal noise.

3. Lubrication status inspection

Unscrew the oil level observation window and check whether the lubricating oil level is at the center line of the oil mark, and whether the oil quality is turbid, black, or contains metal wear debris; if the liquid level is too low or the oil quality is deteriorated, the abnormal sound is most likely due to dry friction caused by insufficient lubrication.

Check the lubricating oil model to confirm whether it is a special extreme pressure oil for worm gears (220#/320# L-CKE/P is recommended). If gear oil is mixed or the viscosity is inconsistent, it will also cause abnormal meshing noise.

Step 2: No-load dynamic investigation (jog → no-load operation, monitoring abnormalities)

1. Inching test

Turn the motor shaft by hand when the power is off, and feel whether the rotation resistance of the reducer is uniform and whether there is any stuck or frustrated feeling; if there is a 'clunking' sound during rotation, it means the internal worm gear meshing is abnormal or the bearing is damaged.

Power on and jog the motor (1-2 seconds each time), and listen for abnormal sound types: If there is a metal impact sound at the moment of jogging, it is mostly due to the coupling being out of center or the worm axially moving; if there is a continuous 'rustling' sound, it is most likely a bearing failure.

2. No-load operation monitoring

Run without load for 5-10 minutes, and use an infrared thermometer to detect the temperature of the bearing end cover and box body. If the temperature rise of the bearing at one end is >40°C, it means that the bearing has wear, abnormal clearance, or insufficient lubrication.

Use a vibration meter to detect the vibration value of each part of the box. If the vibration speed is >2.8mm/s, and the vibration frequency is synchronized with the rotation speed, it means there is a meshing deviation or the shaft system is unbalanced; if low-frequency resonance sound occurs, the box stiffness or foundation fixation needs to be checked.

Monitor the position of abnormal noise: stand at different directions of the reducer (input end, output end, top of the box). If the abnormal sound is concentrated at the input end, it is mostly a fault of the motor coupling or worm bearing; if it is concentrated at the output end, it is a worm gear bearing or worm gear meshing problem; if it is an overall abnormal sound in the box, it is a resonance or fundamental problem.

Step 3: Partial disassembly and troubleshooting (simple disassembly for suspected fault points)

1. Disassembly of bearing parts

Disassemble the bearing end cover and check whether the bearing raceway has fatigue spalling and whether the cage is deformed and broken; use a feeler gauge to measure the bearing clearance. If the clearance exceeds the design value (usually 0.1-0.2mm), the bearing is damaged and causes abnormal noise.

Check whether the axial locking nut of the worm is loose. If it is loose, it will cause the worm to move and cause abnormal noise due to meshing impact. It needs to be retightened according to the specified torque.