Tension Control On Film Blowing Machine Winding System

Process requirements:

The thickness of the extruded film is changed by changing the ratio of the speed of the main motor and the drawn motor. Therefore, the steady-state speed accuracy of the inverter is required to be high, and the fluctuation of the speed may cause unevenness of the film thickness;

Tension control is required between the extraction and the two nip rollers, the two nip rollers and the left and right windings. Different materials have different tension requirements, and the tension should be independently adjustable;

The receiving shaft leans against the winding rubber roller, and relies on the friction between the winding rubber roller and the receiving shaft to drive the receiving shaft to rotate, thereby collecting the material on the material shaft, and the material tension is independent of the winding diameter;

Plan description:

Using the speed difference method for tension control;

The high-speed pulse port is used to ensure the basic synchronization ratio relationship between the take-up, the two nip rollers and the winding roller, and then the tension potentiometer is used to give a superposition speed to form a tension with the speed difference of the system speed;

Program advantages:

The tension is generated by the speed difference, and the frequency converter works in the open loop vector control speed mode, and the dynamic response is fast, which overcomes the situation that the acceleration torque of the torque motor is small and the deceleration tension is too large;

The motor has a constant torque output during speed control. When the line speed and tension are constant, the winding speed of the winding roller is kept constant, and it will not change due to changes in the material diameter and load. Therefore, the torque motor is overcome from the empty to the full winding process, and the output torque needs to be constantly adjusted in order to maintain a constant tension. Shortcomings. The system is easy to operate.