ATLAS COPCO air compressors' coupling components, I. Common types and features
Elastic coupling
Structure: Composed of two half couplings (connected to the motor shaft and the main machine shaft respectively) and an elastic element (such as a rubber pad or a polyurethane block) in the middle.
Features: It has certain buffering and shock absorption capabilities, can compensate for slight axial, radial and angular deviations, and is suitable for small and medium-sized oil-injected screw compressors (such as the GA 11-75kW series).
Advantages: Simple installation and maintenance, low cost, and can reduce the impact of vibration on the motor and the main machine.
Diaphragm coupling
Structure: Torque is transmitted through a metal diaphragm (usually stainless steel), without the problem of elastic element wear.
Features: High precision, high rigidity, with a smaller allowable deviation range, but high transmission efficiency (close to 100%), resistant to high temperatures and oil contamination, suitable for large or high-pressure models (such as GA 90kW and above series, ZR low-pressure series).
Advantages: Long service life, no frequent replacement of wear parts, suitable for continuous high-load operation scenarios.
Hydraulic coupling
Structure: Power is transmitted through a liquid (usually oil), including pump wheel, turbine and guide wheel, etc.
Features: It can achieve flexible start-up, reduce the starting current of the motor, automatically protect in case of overload, suitable for some special models that require frequent start-stop or load fluctuations.
Advantages: Protects the motor and the main machine from shock loads, prolongs the equipment life.
II. Core functions
Power transmission: Stabilizes the transmission of the motor's rotational power to the main machine, ensuring the normal operation of the main machine rotor.
Deviation compensation: Reduces the slight axial, radial and angular misalignment errors during installation, reduces additional stress caused by misalignment.
Buffering and shock absorption: Absorbs the vibration and shock during operation, reduces noise, and protects key components such as the motor and the main machine bearings.
Overload protection: Some types (such as hydraulic couplings, couplings with shear pins) will disconnect or slip in case of overload, preventing the motor or the main machine from being damaged due to overloading.
III. Maintenance and fault diagnosis
Daily inspection
Regularly observe whether the coupling has abnormal vibration, noise or oil leakage (for hydraulic couplings).
Check whether the elastic elements (such as rubber pads) are aging, cracked or worn, and whether the metal components have cracks or deformations.
Ensure that the coupling protective cover is intact to prevent rotating parts from being exposed and causing safety accidents.
Alignment calibration
After installation or replacement of the coupling components, precise alignment calibration (suggested to use a laser alignment instrument) must be performed; otherwise, it will lead to premature wear of the coupling, heating of the bearings or abnormal noise from the main machine.
After running for a period of time (such as every 6 months), recheck the alignment to prevent deviations caused by foundation settlement or loose bolts.
Common faults and handling
Abnormal vibration / noise: Mostly due to excessive axial, radial or angular misalignment of the alignment or damage to the elastic elements, require re-calibration or replacement of the elements.
Power transmission failure: May be due to diaphragm fracture, elastic block detachment or shear pin fracture, require stopping the machine for inspection and replacement of corresponding components, and also investigate the cause of overload.
High temperature: Usually due to poor alignment or insufficient lubrication (for hydraulic couplings), require alignment calibration or replenishment / replacement of working fluid.
Coupling component selection
The specifications of the coupling components (such as hole diameter, torque grade) need to match the shaft diameter and power of the motor and the main machine. It is recommended to use original Atlas Copco accessories to ensure dimensional accuracy and material reliability, avoiding equipment damage caused by inferior accessories.
