The spline shaft of the ZLY280‑16‑1 hard tooth surface gear reducer is a key torque transmission component. Most of the failure problems are concentrated in three categories: tooth surface wear, spline fracture, and plastic deformation of the shaft body. The various fault phenomena and inducing factors are explained below.
1. Spline tooth surface wear
Tooth surface wear is the most common failure mode of spline shafts. Fault phenomenon: The flanks of the spline teeth are gradually worn and thinned, the matching gap between the spline shaft, the matching gear, and the connecting sleeve continues to increase, and the transmission matching accuracy decreases.
Failure causes:
Poor lubrication conditions: Insufficient lubricating oil supply, mismatched lubricating oil grades, or oil mixed with impurities such as metal particles, causing dry friction and abrasive wear on the tooth surface.
Working condition load impact: The equipment continues to bear vibration and impact loads during operation, which intensifies the relative friction loss between the spline meshing surfaces.
Assembly coordination defects: The side clearance of the spline assembly is too large, which causes impact during torque transmission and accelerates the tooth surface wear process.
2. Spline breakage
Spline fracture is a malignant failure and is divided into two categories: overload fracture and fatigue fracture.
1. Overload fracture
Failure phenomenon: It often occurs in equipment jamming and instantaneous severe overload conditions. Instantaneous shear damage occurs at the root of the spline teeth, and the fracture surface is rough.
Cause of failure: The actual output torque exceeds the upper limit of the component design, which is common when the equipment suddenly gets stuck and the starting impact load is too large.
2. Fatigue fracture
Failure phenomenon: Under repeated long-term alternating loads, fine cracks develop in the spline tooth roots. The cracks continue to expand and eventually cause broken teeth. Typical shell-like fatigue texture can be seen at the fracture location.
Causes of failure: Frequent starts and stops of the equipment, long-term high-load operation; the spline tooth root fillet design is too small, resulting in local stress concentration.
3. Plastic deformation of splines
When the spline shaft encounters abnormal external force, irreversible plastic deformation will occur. Failure phenomenon: the spline teeth are crushed and crushed, pits appear on the tooth surface, and even the entire spline shaft is twisted and distorted, and the meshing transmission function completely fails.
Failure causes: instantaneous impact overload; the strength and hardness index of the spline shaft raw material cannot meet the requirements of the operating conditions.
