Introduction of the use of plastic bottle caps and the temperature standard of plastic bottle cap molds

Update:03 Apr 2020

1. Improve moldability: Each plastic part has its proper mold temperature for molding plastic bottle caps. During the production process, if the mold temperature can be maintained at all times, the moldability of plastic parts can be improved. If the mold temperature is too low, it will reduce the fluidity of the melt of the plastic parts, make the plastic parts unclear, and even the die is dissatisfied. If the mold temperature is too high, it will cause deformation of the plastic parts during demoulding and after demoulding, reducing its shape and dimensional accuracy.

2. Molding shrinkage rate: The mold temperature adjustment system is used to keep the mold temperature constant, which can effectively reduce the shrinkage fluctuation of plastic parts molding and improve the qualification rate of plastic parts. Adopting the allowable low mold temperature is helpful to reduce the molding shrinkage rate of plastic parts, improve the dimensional accuracy of plastic parts, shorten the molding cycle, and improve production efficiency.

3. Control the deformation of plastic parts: The temperature difference between the mold core and the cavity is too large, which will cause the plastic parts to shrink unevenly, resulting in warpage and deformation of the plastic parts, especially for plastic parts with uneven wall thickness and complex shapes. Appropriate cooling circuit should be used to ensure the uniformity of mold temperature 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, to avoid changes in dimensions during storage and use. For flexible plastics, the use of low mold temperature is conducive to the stability of plastic parts.

5. Mechanical properties: Appropriate mold temperature can improve the mechanical properties of plastic parts. If the mold temperature is too low, the internal stress of the plastic parts will increase, resulting in obvious welding marks. For rigid plastics with relatively high viscosity, the use of high mold temperature can greatly reduce the stress cracking phenomenon.

6. Appearance quality: Too low a mold temperature will cause the plastic parts to have unclear outlines, obvious defects such as silver filaments, moire, etc., and the surface is absent and rough. By appropriately increasing the temperature of the plastic bottle cap mold, the appearance quality of plastic parts can be effectively improved.