Plastic bottle cap production process
Plastic bottle caps Generally speaking, the production process is roughly divided into two types: compression molding production process and injection molding production process.
The production process of the compression molding cover: 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, and the upper and lower molds are closed, Compression molding and cooling set, demoulding, and then through the ring cutting, padding, complete the production of compression molding.
The production process of the injection molding cap: 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, and is cooled and shaped in the cavity, and demoulded, and then After the ring is cut and padded, the production of the injection cap is completed.
The main difference between the two
- 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.
- The compression molding cap has no pouring point, so that it has a more beautiful appearance and better printing effect;
- 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;
- the injection molding cover needs to heat the material to the molten flow state, the temperature is about 220 degrees; the compression molding cover only needs to be heated to about 170 degrees, and the energy consumption of the injection molding cover is higher than that of the compression molding cover;
- The compression molding processing temperature is lower, the shrinkage amount is small, and the cover size is more accurate.