The slitting machine is a pre-press and post-press equipment that slits a large roll of paper, aluminum foil, mica tape and other thin materials into small rolls of different widths. During the use of the slitting machine, its tension will change. The tension of the slitting machine is an important factor in controlling the slitting effect of the product. It is of great help to the running speed, uniformity and stability of the slitting machine, so special attention should be paid.
1. Factors affecting the tension of the slitting machine:
1. The change in the lifting speed of the slitting machine will inevitably cause a change in the tension of the entire system equipment of the enterprise.
2. During the entire process of rewinding and unwinding of the slitting machine, the straight diameter of rewinding and unwinding is constantly changing, and the change in the straight diameter will inevitably lead to changes in the tension of the raw materials.
3. The looseness of the raw material roller will also cause changes in the strength of the entire equipment.
4. Divide the asymmetry of the raw materials. For example, the fluctuation of the ductility of the raw materials, the changes in the thickness of the raw materials along the total width, length and short directions, etc. The mass axial force of the coil, as well as the changes in its manufacturing working temperature and ambient humidity will also cause damage to the tension fluctuation of the entire slitting machine equipment.
5. The slitting machine transmission system organization (such as guide rollers, corrugated rollers, expansion rollers, etc.) has unbalanced and unstable standard air pressure and other factors.
2. Slitting machine tension control method:
The slitting machine tension control method is generally divided into open-loop control method and feedback control method. Open-loop operation is to immediately use a motor with similar winding characteristics, n=kD (n is the speed ratio, k is a constant, and d is the diameter of the winding roller) to drive the system winding organization to obtain similar constant tension operation. Open-loop operation has poor randomness and low linearity.
There are two types of tension control in closed-loop control: instant tension control and indirect tension control. In the specific production process, the adjustment amount, that is, the tension, is fed back and compared with the given tension. Then, the error effect is used on the controller to adjust the controlled target so that the output tension takes into account specific requirements. This operation method is called instant tension feedback control, which can eliminate steady-state errors without considering various compensations; indirect tension control is to use the motor rated power-torque characteristic curve to control the torque according to the operating speed, so as to achieve the purpose of controlling tension, but this method must be compensated for daily dynamic and static data.
Sometimes, in order to obtain more precise control characteristics, the composite tension control method is selected to adjust the slitting machine tension, that is, first determine the required control amount according to the indirect control system, in addition, consider various compensations to make the indirect control as precise as possible, and then use instant tension control to make adjustments.
