In the various processes of weaving, dyeing and finishing, the fabric (cloth) is subjected to a large warp tension, so the fabric has warp elongation and weft contraction. For example, if such a cloth is used to make clothing, after washing, The clothing will be deformed, such as shrinkage, or even unable to wear. For this reason, in the last process of dyeing and finishing, a shrink-proof finishing is added to ensure that the width of the fabric is not changed after shrinking. Stability, so that the warp yarns of the fabric may be retracted. The fabric should be in a state of almost no tension during the pre-shrinking process. Therefore, there should be a certain amount of space between the unit machines (pre-shrinked cloth, rubber blanket shrinking, and felt finishing) The speed difference, that is, each unit should maintain a proportional synchronous operation for the fabric yarn to retract. At the same time, parameters such as pressure roller temperature and fabric humidity will also affect the preshrinkage rate. For this reason, temperature and humidity should be controlled according to process requirements.