The design of the pepperball shell mold must calculate the size of the pepperball shell mold cavity before opening the mold. As we all know, the pepperball shell is the same as other plastic products. The product taken out of the mold is cooled, and the actual measurement size of the pepperball shell and other plastic products It is smaller than the size of the mold cavity. The main original picture is that plastic products will shrink.

Plastic products have the same physical characteristics of thermal expansion and contraction as other products, so the setting of the cavity size of the pepperball shell mold must be designed with reference to the shrinkage rate of the plastic material, and the shrinkage rate of different plastic materials is different, generally The most commonly used plastic products have a shrinkage rate of about 5 per thousand, but like PS pepperball shell, theoretically the shrinkage rate is between 15 to 20 thousand, so the size of the pepperball crust mold cavity The design of the pepperball crust should fully consider the raw material of the pepperball shell, and then design the size of the pepperball crust mold cavity according to the shrinkage rate of the product material. Another point that needs to be paid attention to is that the ordinary small plastic ball is the pepperball shell below 6mm. The plastic ball mold can be designed by referring to the shrinkage rate of the raw material of the plastic ball, but if the diameter of the pepperball shell is 6mm, then the size of the mold cavity must be increased, because the characteristic of the plastic product is the thicker the glue position. , The larger the shrinkage rate, if the design cavity size of the pepperball shell of 12mm or more is produced, the shrinkage rate should be more than double the shrinkage rate of the plastic product, which is the actual size of the mold cavity.