On the one hand, the production process of compression molding:

The suction machine sucks the mixed material into the barrel of the compression molding machine, and after heating to the semi-melt plasticizing state in the barrel, quantitatively extrudes into the mold cavity, the upper and lower molds are clamped, compression molded and cooled, shaped, demolded, and then cut and looped to complete the production of compression molded caps.



On the other hand, the production process of injection molding closure:

The suction machine sucks the mixed material into the barrel of the injection molding machine, and after heating to the molten plastic state in the barrel, it is injected into the mold cavity, cooled and shaped in the cavity, demoulded, and then cut and padded, and then complete the production of injection molded caps.



The main difference between the two production processes



1. The injection mold is large in volume, and the replacement of a single cavity is troublesome; each cavity of the compression molding is relatively independent and can be replaced separately.



2. The compression molding cap has no pouring point, so that it has a more beautiful appearance and better printing effect;



3. Fill all the cavities once at the time of injection molding, and extrude one cap material at a time. The compression molding extrusion pressure is small, and the pressure required for injection molding is relatively high;



4, The injection molding closure needs to heat the material to the molten flow state, the temperature is about 220 degrees; the compression molding closure only needs to be heated to about 170 degrees, and the energy consumption of the injection molding closure is higher than that of the compression molding closure;



5. The compression molding temperature is lower, the shrinkage is small, and the plastic cap size is more accurate.