It can be divided into three sections in the longitudinal direction of the stainless steel strip for analysis. The first section is a stainless steel strip head, which includes stainless steel strips taken from the pinch rolls to the time when the stable take-up tension is established. It is about 20m. During this time, the coiling process has not reached a steady state. Although the strip has reached a relatively good centering state by two short strokes before being bitten into the pinch roller, it is assisted after biting into the pinch roller. During the movement of the roll, the sides of the head are in an unconstrained state, and the "sickle bend" of the head may cause misalignment of the take-up.
In addition, sometimes the shape of the head of the stainless steel strip is not completely symmetrical, and the stainless steel strip will bite into the initial stage of the auxiliary roll, and the two sides will be unevenly wound, resulting in a misalignment of the winding position of the first ring, forming a certain inner Tower shape. In addition, when the parallelism of the roll and the roll is poor, the force of the stainless steel strip head is uneven, thereby forming an inner tower shape.
The second section is the strip taken up between the reel and the take-up device after the stable take-up tension is established and the strip tail is removed from the equipment. During this time, the reel and the device establish a stable take-up tension, and the side guides are in the state of dynamic rectification control. Even if the side guide opening is too large or too small, ITV monitoring can ensure Timely correction. Therefore, the control of the second paragraph is relatively simple, and the stainless steel coil tower or bread roll caused at this time is also relatively small.
The third paragraph is the strip that is taken up from the time when the stainless steel tail is left from the equipment to the full coiling, and its length is equal to the distance between the equipment and the reel, which is about 120m. During this winding process, the tension of the strip will be greatly reduced rapidly, and any poor shape will be manifested significantly, which will directly affect the shape of the roll and create an outer tower shape. In actual production, the probability of the outer tower shape is relatively high, and the tower shape is also large. When the ideality of the shape control is insufficient, the effect of controlling the ratio of the tension of the stainless steel strip to the pressure of the pinch rolls is obvious for controlling the outer tower shape. The operator can also optimize the outer tower shape of the stainless steel coil by adjusting the pressure on one side of the pinch roller according to the experience and the observation of the ITV.