In the process of modern papermaking industry production and processing, the processed paper products need to be wound into a tube. In this process, the quality of the winding will directly affect the quality of the product. If the winding is too tight, it is easy to cause the product to deform or break; if the winding is too loose, it is easy to cause the product to be loose, which is not conducive to packaging and handling.
Due to the high requirements for winding quality in the papermaking industry, it is necessary to rely on magnetic particle brakes to apply a certain tension on the fabric and keep the tension at a constant value. And the magnetic particle brake can monitor the acceleration, deceleration or stop state of the tension control system in real time to ensure that the product can be produced safely.
The magnetic particle brake uses magnetic particle to form a chain structure under the action of the magnetic field, and controls the friction force by adjusting the excitation current to achieve torque output. This equipment is mainly used for winding and unwinding tension control in papermaking machinery. Its advantages include fast response, low slip loss and frequent start and stop.
The unwinding and winding tension control of the magnetic particle brake on the papermaking machine is mainly achieved by adjusting the magnetic force. The entire coil tension control system is powered by a motor, the magnetic particle brake outputs torque, and the tension sensor monitors the coil status in real time.
Core Features Of Magnetic Particle Brake
- Torque is proportional to current: the change of excitation current can accurately adjust the output torque to meet different process requirements;
- Constant slip torque: when the excitation current is stable, the transmission torque is not affected by the speed difference, ensuring stable tension;
- Wide adjustable range: usually covers 5%-100% of the rated torque, adapting to different working conditions.
- High control accuracy: with fast response capability, it can quickly respond to tension changes to avoid winding too tight or too loose;
Unwinding Tension Control
- Water-cooled magnetic particle brake: heat dissipation through the water circulation system to avoid magnetic particle adhesion or coil damage due to overheating;
- Fully automatic control: cooperate with the tension sensor to monitor the coil tension in real time, automatically adjust the magnetic particle brake current, and keep the tension constant;
- Application scenario: suitable for accurate unwinding of paper, plastic, rubber and other materials to avoid material stretching deformation or wrinkles.
Winding Tension Control
- Magnetic particle clutch coordination: The winding end adopts a magnetic particle clutch to control the unwinding speed and tension by adjusting the input current;
- Closed-loop control system: Combined with the tension sensor feedback, dynamic adjustment is achieved to ensure uniform winding tightness;
- Key role: Prevent the coil from being too tight and breaking or too loose to affect the handling efficiency.
Control Strategy
- Manual mode: The operator adjusts the current through the regulator to achieve basic tension control;
- Automatic mode: The PLC or controller automatically adjusts the magnetic particle brake according to the sensor data to achieve precise control;
Quality assurance: Improve the surface quality of the coil and reduce material loss by accurately controlling the tension.
Precautions
- Avoid moisture on the magnetic particle : Moisture on the magnetic particle will lead to unstable performance. It is necessary to ensure the sealing of the equipment to avoid oil and water from invading the interior. Key parts such as the gearbox need to be completely sealed with a film to prevent oil leakage.
- Temperature control: The surface temperature shall not exceed 90℃ during continuous operation (not more than 90℃ for water-cooled type and not more than 60℃ for air-cooled type), otherwise the durability will be reduced.
- Regular maintenance: Check the rotor concentricity regularly to avoid uneven torque or jamming due to eccentricity.
Conclusion
Through the above methods, the synergy of magnetic particle brake and tension controller can effectively improve the accuracy and efficiency of unwinding and rewinding of papermaking machines and meet the needs of high-end manufacturing. In short, magnetic particle brake is mainly used in the winding process of papermaking machinery to achieve stable winding quality by accurately controlling the tension.