1. Because the melting of raw materials of sheet metal before laser cutting, a part of the cold dry solid in the confluence, resulting in a wireframe like solution line. 2. Because the gas with the evaporation of raw materials is closed. 3. There is residual film remover in the die. 1. In addition, if you want to prevent the solution joint mark, only change the part of the glue inlet to make the solution joint mark visible to be seen. 2. The pin on the abrasive tool (the hole on the matching product) will generally produce solution marks. 3. Because the gas is closed causes a lot of weld lines, so the gas must escape completely after the sheet metal cutting. 4. It is also effective in this way: the area causing the weld line is generated on the unnecessary sheet of the product, then the sheet is disconnected. 5. If there is too much film remover, the front part of the melted raw material will float up be sent into the die, there will be no doubt that there will be weld marks. 3、 Manufacturers talk about solutions:   

1. Temporary way: increase the ejection rate, increase the temperature of the grinding tool, raise the temperature of the barrel, increase the working pressure of the ejection. 2. In the short term: lift change the exhaust pipe slot. 3. Long term way: change the position, specification other mold design of the rubber inlet.