The function of the blanking opening is to hold the parison and seal it during the blow molding process. The most important thing to note when designing the blank is the amount of blank left in the two molds.
If the blank of the blank is designed to be small, the blank will be cut, which will cause air leakage when blowing the product, and the product will not meet the design requirements. If the design of the blanking margin is large, the material will be difficult to fall off, which will cause difficulties for later work.
When designing the blanking distance, only the thickness of the blank and the characteristics of the raw material are taken into consideration to obtain a suitable distance. Generally, the width of the cutting edge of the cutting blank is 1 to 2 mm, and the cutting edge angle is 15 to 30 degrees.
The residual trough is usually disposed on the left and right sides of the blank of the blank, or penetrates on the left and right sides of the blank, and the size is determined according to the width and thickness of the parison after being clamped and clamped, and the mold can be tightly closed.