1. Check for "hidden damage" during transportation and storage
From leaving the factory to arriving at the site, the reducer will undergo long-distance transportation, multiple loading and unloading, etc. As an exposed part, the output shaft is easily susceptible to bumps, scratches or micro-cracks that are not easily noticeable to the naked eye due to collisions and drops during transportation. These surface defects may seem harmless when the equipment is stationary, but once it is put into operation, under the action of high torque and alternating stress, they will become sources of stress concentration cracks, leading to fatigue fracture of the shaft body. Pre-installation inspection is to prevent such "transportation damage" before going into production.
2. Avoid "assembly with injuries" to aggravate the damage
If the output shaft itself is damaged (such as journal scratches, keyway deformation), when the coupling, pulley or gear is subsequently installed, these damaged parts will produce abnormal friction or clearance with the mating parts, resulting in:
Decreased fit accuracy: Excessive shaft diameter ovality and cylindricity will affect the assembly quality of bearings and couplings, causing concentricity deviations;
Seal failure: journal damage may damage the sealing surface of the oil seal, causing oil leakage;
Secondary damage: Forced installation will further expand the original damage and even damage the internal gears and bearings of the reducer.
3. Core measures to prevent shaft breakage failure
According to industry statistics, improper installation and defects in the shaft itself are the two main causes of reducer shaft breakage. The failure process of output shaft fracture is usually:
Crack initiation: Microcracks occur at surface damage or processing defects on the shaft;
Crack expansion: Under the action of alternating torque, the crack gradually expands toward the axis;
Final fracture: When the remaining section cannot withstand the working torque, the shaft body is suddenly twisted.
The purpose of pre-installation inspection is to identify and deal with the "crack initiation" stage to avoid catastrophic fracture after the equipment is in operation.
4. Ensure concentricity and transmission accuracy
The output shaft of the DCY series reducer usually needs to be accurately aligned with the main shaft of the working machine. If the output shaft itself has bending deformation or journal wear, even if it is carefully adjusted during installation, the concentricity requirements in long-term operation cannot be guaranteed. Disagreement can lead to:
The output bearing is subject to additional radial force (bending moment), which accelerates fatigue fracture;
Poor gear meshing produces vibration, noise and tooth surface pitting;
Early damage to the bearings will shorten the life of the entire machine.
