The bending deformation of PVC profile is a common problem in the extrusion process. The main reasons for the injection molding process are as follows: uneven exit of the die; When cooling is stereotyped, the material is not sufficiently cooled, and the amount of post-contraction is inconsistent; Equipment and other factors. The old master suggested that we should solve this problem in the following ways:
1. Ensure the concentric and horizontal degree of the extruder across the board. Each time the mold is replaced, the concentric and horizontal degree of the extruder, die, mold, water tank, etc. should be corrected.
2. Carefully assemble the die before starting, so that the clearance of the various parts is consistent. If the material output of the die is found to be uneven during boot, the deformation direction of the die can be adjusted according to the bending direction of the die, and the temperature of the die can be adjusted to ensure that the die output is uniform, such as adjusting the die temperature is invalid. The plasticization of materials can be improved appropriately.
3. Adjust the cooling system of the stereotyped die, and add the amount of cooling water on the side of the large material that bears the tensile stress.
4. Adopt the method of mechanical offset center adjustment, that is, adjust the positioning bolt in the middle of the stereotyped mold while producing it, and make a reverse micro-adjustment according to the bending direction of the profile(this method should be cautious, and the adjustment amount should not be too large).
5. Pay close attention to the working quality of the mold, pay attention to the maintenance of the mold, and maintain and maintain the mold at any time according to the actual situation.