Warping is the second process of weaving preparation. The purpose of warping is to wind a certain number of packages, in the length and arrangement of the design, in parallel with the warp beam or the weaving shaft, in preparation for the warp system constituting the fabric. The quality of the warping process has a direct impact on whether the sizing process can proceed smoothly and the appearance of the fabric. To this end, the process requirements for warping are:
       1, Tension, winding and arrangement are uniform, that is, the tension between the warp yarns which are required to constitute the yarn is uniform during the warping process; the warp tension is always uniform during the winding process; the warp yarns on the warp beam are uniformly spaced and evenly arranged.
       2, The appropriate tension, so as to ensure a certain warp beam winding density, but also to maintain the physical and mechanical properties of the warp yarn original elasticity and strength.
       3, Warping number, warping length and yarn arrangement (including color yarn arrangement, color matching cycle) should meet the requirements.
       4, The joint quality should meet the requirements.
       The warping process differs depending on the type of yarn and the process characteristics. The warping methods used are as follows:
       First, the batch warping method
       The batch warping method is to divide the total number of warp threads required for the fabric into several batches according to the number of cartridges that can be accommodated on the creel, and respectively wind them on several warp beams, and then put the several warp beams in the pulp. The yarn machine or the parallel machine is combined and wound into a length of the weaving shaft. The total number of warp yarns on the weaving shaft is the total number of warp yarns required for the fabric.
       The advantages of the batch warping method are high production efficiency, good warp quality At, good sizing, and suitable for mass production. It is the main method adopted by cotton textile mills.
       The disadvantage of the batch warping method is that it is difficult to maintain the order of the color yarns when the warp beams are combined. This method is mainly applied to primary colors or monochromatic fabrics, and a small number of colored yarns with less complicated color arrangement can also be applied.
       Second, the division of warping law
       The slitting warping method is to divide the total number of warp yarns of the fabric into several parts according to the arrangement cycle and the capacity of the creel, and then to wind up in parallel according to the width and length specified by the process. On a large roller. After all the strips are full, they are retracted from the large drum and wound onto the weaving shaft, which is called the inverted shaft. Therefore, the slitting warping method can directly obtain the weaving axis. The slitting warping method is characterized by the order in which the colored yarns are arranged. Because the batch warping method has a small batch size, it is applied to complex production of small batches of yarn-dyed, wool-weaving, silk weaving, etc.
       The shortcomings of the split warping method are: the tension of the weaving shaft is not easy to be uniform, and the parking operation time such as changing the strip, the reverse shaft and the joint is too much, and the production efficiency is not high, so the number of strips should be less under the condition that the capacity of the creel is permitted.