Causes of severe quilting 2.1 If the pressing force is too low, the welding force is low. The factors causing the low extrusion force are comprehensive, and there are some factors on the mold as well as the process. There are the following situations: First, the extrusion is relatively low. To increase the welding force, the following methods can be used: 1/ Upper die thickening 2/Shunt hole is properly reduced 3/Extrusion temperature is appropriately reduced, normal hollow profile extrusion temperature is 460-500°C, which can be reduced to 420-440°C . This method is very practical at the scene. 4/ Select a larger extrusion tube, that is, arrange the extrusion on a larger model. 5/ The choice of welding room is deeper (can be done by "sinking" the shunt bridge). However, it should be noted that the sink bridge will also reduce the squeeze force, so the use of this method depends on the specific circumstances. For the use of "+ Yu" bridge structure of the shunt mode is more effective. In fact, in the production process, along with the wear of the mold, the wall thickness of the profile also increases, and the extrusion ratio also decreases. To a certain extent, the seriousness of the weld will affect the surface quality of the profile.