What is the reason for the periodic clanging sound of NGW gearbox when it makes an impact sound

The periodic "clanging" impact sound of NGW reducer (a common planetary gear reducer) usually indicates a serious mechanical failure of the internal transmission components. This sound is often accompanied by a noticeable impact, and it is recommended to immediately stop the machine for inspection to prevent the fault from escalating and causing more serious damage.

Based on the structural characteristics of NGW reducers, the main causes of this periodic impact sound are usually concentrated in the following aspects:

1. Serious damage to gears (broken or broken teeth)

This is the most common and dangerous reason. When the sun gear, planetary gear, or ring gear inside the reducer has broken teeth or broken angles, every time the gear rotates, the broken part will collide with the mating gear, resulting in a crisp and periodic "clang" or "click" sound. As the running time increases, this kind of impact sound often becomes more intense and may be accompanied by body vibration.

2. Excessive gear mesh clearance

Due to long-term wear, loose bearings, or changes in center distance, the backlash between gears severely exceeds the standard. During operation (especially when there is a change in load or when switching between forward and reverse directions), there will be an "empty stroke" between gears, and sudden collisions between tooth surfaces will produce a "clang clang clang clang" sound.

3. Severe damage to bearings

If the bearing balls, raceways, or retainers inside the gearbox are broken, peeled off, or severely worn, the rolling elements will undergo periodic impacts at the damaged parts. This type of malfunction not only produces intermittent "clanging" sounds (particularly evident during start stop or sudden load changes), but is usually accompanied by abnormal high temperatures and severe vibrations in the bearing seat position.

4. Internal foreign objects or loose parts

If metal debris, broken bolts or other foreign objects fall into the reducer, or if a fastener inside (such as a planetary carrier bolt) becomes loose and falls off, they will be swept into the meshing area during gear operation, causing irregular or periodic "click" and "clang" collision sounds.