Production process of PVC toys

In toy production, it is often the problem that the head or hands and feet of PVC dolls are easily twisted from the neck that connects the body. In addition to design and material issues, injection molding problems are also a very important reason. Sometimes in the same set of molds, there are several identical injection parts, some twisted and some are easy to be twisted. Even the same cavity injection molded parts will sometimes twist continuously, and sometimes it is easy to twist. Therefore, injection molding technology and production control have become quite important.

Therefore, in the production process, it is first necessary to ensure that the molten adhesive has a sufficient temperature, and the back pressure of the foot and the melting adhesive time should be properly applied to make the molten adhesive mature and have good flowability. Otherwise, it is unmelted glue, enough to make the connection easily disconnected.

Secondly, as long as the product structure allows, try to increase the transition angle of the connection, preferably up to R1.0 mm or more, so that when the melt passes through the corner, there will be no eddy currents caused by the skin. At the same time, increasing the transition fillet can also prevent stress concentration and increase the tensile strength of the joint.

The third is to control the injection speed, which is the most critical point. When adjusting the machine, a lower speed must be used so that the melt fluid flows smoothly from the end of the mushroom to the cavity of the head or hands and feet. (water lines and cow dung lines). The cause of crusting is that when the melt flows from the small end to the large end, the volume suddenly changes and eddy currents are generated. Therefore, reducing the glue injection speed can reduce the energy generated by eddy currents. In addition, due to the good transition angle, the glue can pass smoothly through the connection without generating eddy currents, thus achieving the purpose of eliminating the skin.