How to adjust the input torque of WHX125-50 worm gear reducer

The WHX125-50 worm gear reducer does not have a built-in torque adjustment mechanism. The input torque is determined by the drive motor and the load. It needs to be adjusted through three methods: motor control, transmission matching, and overload protection. The following are directly implementable solutions:

1. Core principles

WHX125-50 is a fixed speed ratio (i=50) arc tooth worm reducer, input torque T₁ = output torque T₂ ÷ 50 ÷ efficiency η (η≈0.75~0.85).

The upper limit of input torque is determined by the rated torque of the motor and the allowable input torque of the reducer, and cannot exceed the rated value.

2. 4 practical methods for adjusting input torque

1. Motor control and adjustment (most commonly used, can be directly operated on site)

Frequency conversion speed regulation (recommended): Use a frequency converter to adjust the motor speed/frequency and change the output torque synchronously.

Reduce the frequency → the speed decreases → the output torque increases → the input torque increases simultaneously;

Increase the frequency → increase the speed → decrease the output torque → decrease the input torque synchronously.

Current/torque limit: Set the maximum output current/torque upper limit in the frequency converter or motor driver to limit the input torque peak and prevent overloading.

Voltage adjustment: Reduce the motor supply voltage and reduce the input torque (suitable for small-range fine-tuning, efficiency slightly reduced).

2. Transmission matching adjustment (change system torque distribution)

Replacing the drive motor:

Need greater input torque: change to a motor with greater power and higher rated torque;

Need smaller input torque: Change to a motor with smaller power and lower rated torque.

Install a torque limiter/safety clutch: Install it between the motor and the input shaft of the reducer. Set the slip torque value. If it exceeds the value, it will slip to protect the reducer and motor.

3. Load side adjustment (indirect change of input torque)

Reduce load: reduce equipment resistance, reduce workload, and input torque will decrease accordingly.

Optimize the transmission mechanism: clean up stuck and poorly lubricated parts, reduce friction losses, and reduce input torque requirements.

4. Maintenance of the reducer body (guaranteed rated torque output)

Check the worm axial clearance: adjust the bearing gland nut to eliminate excessive clearance and avoid torque loss.

Ensure the quantity and quality of lubricating oil: Use N320~N460 worm gear oil, and the oil quantity meets the standard to prevent efficiency decline and torque abnormality due to insufficient lubrication.

Check the worm gear mesh: ensure good contact, no offset load, pitting corrosion, and avoid additional torque loss.

3. WHX125-50 key parameters

Center distance: 125mm; speed ratio: i=50; input speed ≤1500r/min.

Allowable input torque: about 150~200N·m (according to standard JB2318-79).

Maximum output torque: about 7500~10000N·m (50×input torque×efficiency).

4. Adjustment steps and safety points

Stop the machine and cut off the power, confirm the load status, and clarify the target input torque range.

Prioritize using the frequency converter to adjust, gradually adjust the frequency/current, and observe the operating status.

When installing a torque limiter, the setting value is 1.1~1.2 times the rated input torque.

After adjustment, conduct a no-load/light-load test machine to check temperature rise, abnormal noise, and oil leakage, and confirm that the torque is stable.

It is strictly prohibited to operate beyond the allowable input torque to avoid damage to the worm gear, bearings and box.