Couplings may experience fatigue failure, failure of the connecting components, or transmission shaft fractures, among other failure modes, even when manufactured to the required precision and installed and used correctly. Generally, replacing the connecting components or elastic elements is sufficient to allow the coupling to continue operating normally.
Many factors can affect the service life of couplings, starting with the material, heat treatment, and manufacturing precision of the couplings themselves. For instance, the choice of casting or forging materials must be made carefully, and the corresponding heat treatment must be strictly enforced to ensure the coupling material performs as intended. Additionally, the stability and smoothness of the drive shaft system are crucial; for example, shaft system vibration due to drive shaft failure or sudden, severe overloading of the equipment during use can lead to drive shaft breakage.
Under normal circumstances, the failure of rigid couplings is primarily due to the connecting bolts, which can be replaced promptly. It is also necessary to inspect whether the bolt holes have deformed. If deformation occurs, the deformed bore should be reamed using a reamer, and the end face deformation of the deformed bore should be repaired. Replacement or enlargement of the bolts (bushing bolts) is required. If the drive shaft breaks.
To reuse the coupling, it must be disassembled and inspected for deformation of the internal bore. Generally, the internal bore surface should be plated with hard chrome or coated, and then ground to meet the precision requirements for use. Similarly, the failure of elastic couplings is primarily due to the failure of the elastic elements.
Generally, replacing the elastic elements is sufficient. However, this repair method is employed only when there is deformation in the coupling's inner hole or failure of the keyway. It is important to note that the repair of a coupling should be properly differentiated based on actual usage and the manufacturing precision and strength of the coupling itself. Before repairing, it should be checked for any cracks (mechanical flaw detection, etc.) or deformations, or if the equipment needs continuous use while the new coupling is temporarily unavailable.
(1) Basic inspection requirements: The connections must be secure, with no looseness in the connecting bolts or keys. There should be no noticeable jumps in radial and end face during transmission, and no visible discrepancies upon visual inspection. When checked with a gauge, the measurements should not exceed the limits.
(2) Gear-type stability inspection: It requires disassembly for inspection when there is an increase in transmission noise or when major product repairs are being carried out.
(3) Elastic Inspection: Replace the rubber rings and pads promptly upon destruction. If the pin and hole are destroyed and cause vibration, rotate the half-body by an angle and drill a new hole. Replace with a standard new pin; do not enlarge the original hole and fit a new pin.
(4) There are issues such as the seal being compromised in the lubricating oil series, oil degradation, and oil leakage. In the event of these occurrences, the seals and oil must be replaced, and oil should be replenished promptly when depleted.
