Main way of tension control
The tension control method is generally divided into two types: open loop control mode and closed loop control mode. The open loop control is to directly drive the winding mechanism with an electric motor having a similar winding characteristic n = kD (n is the rotational speed, k is a constant, and D is the diameter of the winding roller) to obtain an approximate constant tension operation. The open loop control has poor randomness and low control precision. The closed loop tension control has two kinds of direct tension control and indirect tension control. In the actual production process, the volume is adjusted, that is, the tension is fed back, compared with the given tension, and then the difference is applied to the regulator to adjust the controlled object so that the output tension meets the actual demand. It is called direct tension closed-loop control. This method can eliminate the steady-state error without considering various compensations. The indirect tension control uses the motor speed-torque characteristic curve to control the torque to control the torque, so as to achieve the purpose of controlling the tension. This method requires dynamic and static compensation. Sometimes, in order to obtain more precise control performance, a composite tension control method is adopted, that is, the required control amount is first determined according to an indirect control algorithm, and various compensations are considered to make the indirect control as accurate as possible, and then the direct tension control is used for fine adjustment.
Reasons, countermeasures and effects of BOPP film slitting quality ---
twelve. Interface quality problem (poor interface quality, interface identifier does not match)
1. Interface requirements
Due to poor interface, the quality of the film roll may be broken or wrinkled, which may cause adverse effects in the user's use. Therefore, the film interface must be connected to the specified specification to ensure the joint quality of the interface. Specific requirements are as follows:
1 The two sections of the joint are cut and flattened horizontally, and the beige (or other specified color) adhesive tape with a width of 72 mm is firmly adhered to the front and back sides of the film;
2 In order to improve the interface quality, the film interface is required to be straight and balanced with the paper tube direction, and the interface is required to be flush and wavy. The interfaces at both ends are in the middle of the tape. Try to avoid the size of the edge. The adhesive tape is attached to the film. No obvious bubbles;
3 The film surface at the interface is required to be smooth without obvious wrinkling;
4 Do the identification of the joint position as specified.
The basic knowledge of the slitting machine and its development process --
Basic knowledge and development of slitting machine
In the modern packaging industry, the slitting machine is a relatively important equipment that is often used before and after printing. The raw materials are mainly cut before printing, such as paper, plastic film and so on. This is a process that raw material manufacturers must complete in order to meet the width requirements of packaging manufacturers such as customers. The slitting machine is used to divide the printing and composite film of a plurality of sets of patterns of a fixed width into a finished film roll to adapt to the subsequent automatic packaging and bag making process.
With the improvement of flexible packaging automation and consumer goods manufacturers focusing on reducing the inefficiency and pollution of intermediate links, some manufacturers have gradually changed the process and replaced manual packaging with more automated automatic packaging lines. As the demand for coils continues to increase, the position of the slitter is becoming more and more important, and higher requirements are placed on the efficiency of the slitter.
Zhengzhou EAST IMPORT AND EXPORT co., ltd . ( a goulian group of company) a manufacturer and exporter for all kind of packaging machinery , like bopp tape coating machines, bopp tape slitting machines. Bopp tape core cutter, bopp tape core loader etc