What problems will occur if the sun gear and the inner ring gear of the NGW-S62-56 reducer are not concentric?

When the sun gear of the NGW-S62-56 reducer is not concentric with the internal ring gear, the most direct and serious consequence is gear meshing eccentric load, which in turn causes a series of chain failures such as increased vibration, increased noise, accelerated local wear, and significantly shortens the service life of the equipment. This problem is particularly sensitive in high-precision transmission systems and must be taken seriously.

1. Core fault performance

1. Gear meshing unbalanced load and local wear
   ‌ Non- concentricity causes the center distance between the sun gear and the internal ring gear to be inconsistent in the circumferential direction, causing the tooth surface contact on one side to be too tight and the other side to be too loose. The contact stress in areas where stress is concentrated can exceed the design value by more than 30%, and pitting corrosion, spalling and even micro-spot welding can quickly occur.

2. ‌Abnormal Vibration and Periodic Noise‌The
   eccentric load causes the planet wheel to receive uneven force during its revolution, resulting in periodic impact vibration that is synchronized with the planet carrier speed. The scene often manifests itself as a low-frequency 'roaring' or 'clunking' sound. In severe cases, the amplitude of the whole machine can reach more than 0.15mm, far exceeding the normal value (<0.08mm).

3. ‌Local temperature rise and risk of overheating‌Heat accumulates in areas where
   friction is concentrated, causing the local temperature of the box to rise abnormally. If not discovered in time, continued high temperature may cause the lubricating oil film to fail, further aggravating direct metal contact, which may eventually lead to tooth surface gluing or bearing 'locking'.

4. ‌The force of the planetary gear assembly is unbalanced‌The load distribution
   of each planetary gear is uneven, and some planetary gears have been overloaded for a long time, which can easily cause the planetary gear shaft to bend, the planetary carrier to deform or even break. Actual measurement data shows that when the assembly eccentricity is 0.05mm, the load of a single planet wheel can increase by more than 40%.

2. Derivative system problems

3. Fundamental Cause Analysis

• ‌Improper installation‌ : The base is uneven, the anchor bolts are not tightened diagonally, the box is deformed, etc., causing the installation position of the inner ring gear to shift.

• ‌Machining error‌ : The coaxiality of the mating surface of the inner ring gear and the housing is out of tolerance (>0.03mm), or the connection between the sun gear shaft and the input shaft is not concentric

• ‌Assembly process defects‌ : No gaskets or eccentric sleeves are used to adjust the meshing position, and there is a lack of pre-assembly inspection links

• ‌Deformation during operation‌ : Long-term high temperature or heavy load causes thermal deformation of the box, destroying the original concentric state.