1. Improve the formability: each plastic part has its own suitable mold temperature for forming plastic bottle cap. In the production process, if the mold temperature can be maintained at all times, the formability of the plastic part can be improved. If the mold temperature is too low, it will reduce the fluidity of the plastic melt, make the outline of the plastic part unclear, and even the die is not satisfied. If the mold temperature is too high, the plastic parts will deform when demoulding and after demoulding, and the shape and size accuracy will be reduced.
2. Forming shrinkage rate: using the mold temperature regulating system to keep the mold temperature constant can effectively reduce the shrinkage fluctuation of plastic parts forming and improve the qualified rate of plastic parts. Adopting the allowable low mold temperature is beneficial to reduce the forming shrinkage of the plastic part, improve the dimensional accuracy of the plastic part, shorten the forming cycle and improve the production efficiency.
3. Control of plastic deformation: excessive temperature difference between mold core and mold cavity will cause uneven shrinkage of plastic parts and warpage of plastic parts, especially for plastic parts with uneven wall thickness and complex shape. Proper cooling circuit should be adopted to ensure the uniformity of mold temperature, so as to eliminate the warpage of plastic parts.
4. Dimensional stability: for crystalline plastics, the use of high mold temperature is conducive to the crystallization process, avoiding the size change during storage and use. For flexible plastics, low mold temperature is beneficial to the dimensional stability of plastic parts.
5. Mechanical properties: proper mold temperature can improve the mechanical properties of plastic parts. Too low mold temperature will increase the internal stress of the plastic parts and produce obvious weld lines. For rigid plastics with high viscosity, the use of high mold temperature can greatly reduce the phenomenon of stress cracking.
6. Appearance quality: too low mold temperature will lead to unclear outline of plastic parts, obvious defects such as silver wire and moire, and the surface is matte and rough. The appearance quality of plastic parts can be effectively improved by properly increasing the temperature of plastic bottle cap mold.