Denim fabric quality inspection is generally divided into two times. The first time is the preliminary inspection. The denim grey cloth dropped from the cloth machine is inspected one by one. During the gun inspection, mark the edge t of the cloth for the big defects which are rated as 4 points on the cloth surface. For the identification of finished product inspection and evaluation. Because of some defects of denim fabric, it can't show shrinkage without singeing. Therefore, the general first face of denim fabric quality. Rating. Denim fabric is a kind of fabric that can not be repaired. During the initial inspection, most factories repair some small defects, such as sundry weavers and elastic warp, turn the knots floating on the cloth surface, turn the tip of the cloth trimmer to the bottom of the cloth, and remove the fried tail, residual yarn and floating dust on the cloth surface.   
Another task of preliminary inspection is to find continuous defects, report them to weaving workshop in the quickest way, deal with them in time, and stop the continuous weaving class. The second time is the final inspection, grading and package of finished denim fabric. According to Levis scoring standard, the defects on the fabric surface are scored during silk inspection. If the defect score per square yard is not more than 40 points, it will be rated as ^, and if it is more than 40 points, it will be rated as B. It is a big defect with 4 marks on the cloth surface. It is marked on the edge of the cloth so that the garment factory can clearly identify it when cutting. The number of Weft Defects in the 100 yard length is not specified in the text. Generally, there are no more than four weft defects in the 100 yard length. In some factories with high production level, there are no more than two defects with 4 points of full radiation evaluation.   
It's difficult to achieve the same color of dry VAT in the blue dyeing of denim fabric. Therefore, denim fabric should be strictly separated in the water. Each rolled denim fabric must be colored according to the color board to determine the color number. In order to avoid the difference of color resolution, color matching is best carried out by professional color matching workers under the standard optical box. For factories with better control of dyeing process, Yi color is only divided into three grades. In order to keep the color of denim fabric in a long term, it is necessary to manage the color plate. The color plate should be sealed and stored in a place with weak light.   
The color plate used for color matching should be replaced once a week to prevent the color plate from changing color in air and light and affecting the accuracy of color matching. Some t factories with strict color management not only classify the surface color of finished denim fabric, but also sew the fabric samples of each roll into baijiayi to check whether the background color is consistent. If there is any inconsistency in the table, adjust it in time to ensure the same color of denim and the same color in the warehouse. Before delivery, take out the small pieces of cloth samples left in the cloth meeting and sew them into baijiayi for deep washing. If it is found that the color after deep washing is inconsistent, adjust them to ensure that the same batch of denim fabric will not be different due to different production time or different cylinder number.   
The appearance quality and physical index of denim fabric were also sampled during the face covering process. In addition to the width of denim fabric, the re inspection workers measure each shrinking package unit one by one. Other parameters, such as shrinkage allowance, weft slope, warp and weft density, cloth weight, breaking strength, breaking strength, color fastness, etc., shall be inspected by the quality department according to the batch sampling, so as to determine the delivery grade of this batch of cloth.   
The first and second inspection of denim fabric is usually carried out on the shaking table or horizontal table type cloth inspection machine. Use, I and s to show the healing diagram of inclined face cloth table and horizontal table cloth tester respectively. The general face covering cloth machine is a face rolling combined machine with a rolling cloth. Face rolling, grading, reel and packaging are completed at one time. In some factories, cloth is first coded before rewinding, and then the guns are read one by one on the platform. Finally, it is sent to the coiler for sub packaging, reel and packaging.