Because the tension required in each functional area of the color painting production line is different, the tension roll group is usually placed in the population and outlet position of each functional area. This arrangement has two advantages: one is that the tension in each area of the production line can be kept constant during operation and can be controlled and adjusted separately; the other is that the tension roll group can be placed in the population and outlet position of each functional area. So that each functional area on the production line is separated to form a relatively independent area, the tension of the two adjacent areas will not affect each other. for example
The population section of the production line is usually separated from the population looper by tension roll group No. 1 (see Figure 3-2). During the operation of the production line, when the last coil of steel strip is gone and new coils are needed, the population section should carry out a series of operations, such as trolley feeding, uncoiler uncoiling, tape cutting head, tail seam with the last coil, deburring and so on. At this time, the No. 1 tension roll clamps the tail of the upper coil through the buffer roll to make the entrance section relatively independent, while the entrance looper releases the original stored steel strip quantity according to the speed of the process section by releasing the looper. Section maintains normal operation. The No. 2 tension roll group is used as the separating point between the inlet looper and the process section, because the inlet looper must perform the operation of filling and releasing functions at the beginning and end of each volume, and the tension in the looper is different from the tension requirement of the process section. Therefore, the inlet looper can not affect the operation of the process section.
Several functional areas in the process section also need to be separated by tension rollers. For example, the steel strip cleaning coating area needs more contact surface and more friction because of pressure spraying of alkali solution, brushing treatment of brushing roller of brushing machine and extrusion of extruding roller. Therefore, the zone and the coating zone are usually separated by tension roll No. 3. In addition, the strip in the curing furnace should be stable, the tension fluctuation should be small, and the drape of the strip needs to be adjusted at any time through the tension roll group. Therefore, the initial solidification zone and the cleaning solidification zone are usually separated by tension roll No. 4: 5 between the process section and the outlet looper. No. 1 tension roll set to separate.
Similarly, the outlet section should undertake the cutting of the bottom line and the front and back seams of the color coating roll, and some of them also need to carry out the protective film after coating and other functions. At this time, the outlet looper should also carry out the operation of filling and releasing. Therefore, the outlet looper and the outlet section can not interact with each other, as in the import section, it should be separated by tension roll No. 6.
In addition, the tension roll group not only separates and exerts force to pull the steel strip in each functional area of the production line, but also plays the role of speed reference roll in some positions of the production line. As shown in Figure 3-2, No. 1 and No. 6 tension rolls are speed reference rolls at the entrance and exit sections of the production line, while No. 4 tension rolls are speed reference rolls at the process section of the production line, that is, the speed of No. 4 tension rolls is the speed of the production line. In the production process, regardless of the tension of the speed reference roll, the given speed must be maintained. Through the direct control of the three speed reference rolls, the production line can keep running at a steady speed, such as No. 2, No. 3 and No. 5 tension rolls, as well as the uncoiler and coiler are responsible for matching their corresponding speed base. The quasi-roll tightens the steel strip, which belongs to indirect tension control.
Generally speaking, the more complex the process of the color coating production line is, that is, the more the operating functions, the more the tension compartments and the more complex the tension control will be.