Iron ore cone crusher torque limiting magnetic coupling

The torque-limiting magnetic coupling has structural and functional characteristics that the hydraulic coupling cannot match, mainly in terms of structure, installation, noise and vibration, soft start, heat dissipation, overload protection and environmental protection.

• The torque-limiting magnetic coupling is not only simple in structure, but also has no independent moving parts, so there are no problems such as wear, fragility and seal leakage, which greatly improves its reliability and service life and reduces maintenance costs.
• The conductor disk and the permanent disk are fixed on the motor and load shafts respectively. There is no mechanical constraint relationship between the two except for the interaction of the axial magnetic field force. Therefore, there is no strict restriction on the alignment and inclination error of the shaft system during installation. Generally, the shaft inclination angle is not greater than 1.5° to ensure normal operation, and the difficulty of installation is greatly reduced.
• After installing the torque-limiting magnetic coupling, noise and vibration are greatly reduced. More than 80% of rotating equipment will fail due to vibration, most of which are due to shaft misalignment, in addition to equipment imbalance and resonance. The torque-limiting magnetic coupling is not in physical contact, but transmits torque through the air gap. Experiments have shown that the use of torque-limiting magnetic couplings can isolate up to 80% of vibration transmission.
• Soft start, the starting current is significantly reduced. After using the torque-limiting magnetic coupling, the motor accelerates to the maximum speed at startup. Under the action of the coupling magnetic field, the load starts smoothly and finally accelerates to a speed close to the motor speed. Under normal circumstances, the starting peak current when the system uses a torque-limiting magnetic coupling is only about half of the starting peak current when the torque-limiting hydraulic coupling is connected. In the operation of equipment such as crushers, zipper machines, and belt conveyors, the impact of impact loads during startup and operation is greatly reduced, and the service life of the equipment is extended.
• Torque-limiting magnetic coupling also relies on speed difference to achieve torque transmission. The greater the slip rate, the greater the coupling torque, but the greater the eddy current heat loss; it is converted into temperature rise heat on the conductor and absorbed by the air. Under the same slip rate, the eddy current heat loss decreases exponentially with the increase of the air gap.
• The torque-limiting magnetic coupling has the function of stall and overload protection. When the equipment is working normally, when the torque at the load end suddenly increases and exceeds the safe torque of the transmission device (about 1.8 times the rated torque of the motor), the speed of the load shaft drops rapidly, and the coupling will automatically increase the air gap and enter the “torque disengagement” state to reduce the torque transmission. The torque transmitted in the “torque disengagement” state is about 5% of the rated torque of the motor. The transmission will maintain this state until the load end drops below the safe torque, that is, the fault is removed, the speed of the load end gradually increases, and the torque-limiting magnetic coupling re-enters the normal working state. It can be seen that the overload protection process of the torque-limiting magnetic coupling can be completed automatically and reversibly, without manual participation, safe and efficient.
  The torque-limiting magnetic coupling has a simple structure, is basically maintenance-free, and does not require lubrication, so it does not cause any pollution or damage to the environment.