The first one is production (including spray coating, cloth laying, vacuum pumping, a split line, and trimming). These parts are called semi-finished products The second is to repair (including air friction, water grinding, polishing, and painting) After trimming, the product will enter the semi-finished product warehouse and wait to be assigned to the next department for processing. The significance of a semi-finished product warehouse is the following three points. 1) It can check the quality problems of each product after forming, so as to avoid the flow of products with quality problems into the next step, resulting in a waste of time and labor. 2) The number of products shall be reasonably allocated according to the skills and level of the second step workers to ensure that the goods can be delivered on time. 3) Each product is traced back to groups and individuals, and the defects are caused by the workers are trained and recorded separately. skills of each worker are improved.