During the weaving and dyeing and finishing process, the fabric gathers a large internal stress. The fabric that has not been pre-shrinked is made into a garment. After washing, it will produce a certain degree of shrinkage and deformation. Therefore, the fabric must be placed in the pre-shrinking machine. Reasonable handling in the middle. The pre-shrinking machine adopts a mechanical physical method to retract the fabric in the warp direction, so as to restore the balanced bending state of the yarn, so that it has good dimensional stability, full hand feeling and low shrinkage rate.
Since the pre-shrinking finishing of the fabric is carried out under certain process conditions, the on-line detection and monitoring of the process parameters is realized, and the corresponding humidity, temperature and pre-shrinkage value of the fabric are established to ensure a stable vehicle speed and a stable tension. Only when the process conditions are strictly controlled and stable, can the shrinkage rate be stabilized and the product quality be stable, thereby improving the grade of the textile fabric and at the same time increasing the market competitiveness of the enterprise.
During the working process of the pre-shrinking machine, the control of the major process parameters is very important. In terms of humidity, the humidity signal of the fabric measured by the humidity sensor in the detection system is fed back to the PLC programmable, according to the process requirements, through the relative humidity The adjustment is to intuitively control the moisture content of the fabric, and the humidity measurement range is 3-20%.
The temperature of the pre-shrinking machine is based on the process requirements, through the temperature detection system, the PLC controls the temperature setting of the actuator to the actuator, monitors the surface temperature of the blanket pressure roller, and makes the temperature constant. The temperature is allowed to be in the range. 100 to 150 ° C. There is also shrinkage and tension, the speed signal monitored by the cloth roller encoder is fed back to the PLC to realize the programmable detection pre-shrinkage rate; and the linear velocity of each unit in the system is programmable by PLC. The accuracy ratio relationship is always the same and the fabric tension is constant.http://www.haida-textile.com/