Mold of rotary molding products the mold used for rotary molding is a single wall closed mold, which gives the outline of the product, but the internal outline of the product cannot be accurate to the details. Ordinary carbon steel plate is generally selected as the molding material of rotary mold. The cost of welding die is relatively low, especially suitable for large rotary plastic products. The rotary molding process has the following basic requirements for its mold:

The mold is not easy to deform and deflect in the process of repeated heating and cooling.

The mold shall be attached with a clamping mechanism for easy loosening, so that the mold can be tightly closed in the heating and cooling process, and can be easily opened when the products need to be unloaded and loaded.

The design and installation of rotational molding die should be conducive to the relative movement of air flow around the die surface, so that the die can be evenly heated and cooled.

A vent pipe shall be set for the rotational molding die to prevent the heated expansion of the gas in the die during the heating process from extruding the molten plastic along the die joint, and to prevent the negative pressure in the die during the cooling process from causing the deformation of the die and products.

When designing the local structure of the die, try to avoid deep cavities and holes, as well as structures such as stiffeners and solid protrusions, because it is difficult for powdered materials to cover the surface of the above structure.

Suitable for molding large and extra large parts

In most rotational molding processes, plastic molds are under high pressure in the molding process, such as injection molding, compression molding, extrusion, blow molding, etc., which are widely used. Therefore, when using these molding processes to produce large plastic parts, it is not only necessary to use molds that can withstand great pressure, which makes the molds bulky and complex, Moreover, the plastic forming equipment must also be designed and manufactured very firmly, and the processing and manufacturing difficulty of the machine mold increases accordingly and the cost increases. On the contrary, because the rotational molding process only requires the strength of the frame to be sufficient to support the weight of materials, molds and the frame itself, as well as the mold closing force to prevent material leakage, even for large and super large plastic parts, there is no need to use very bulky equipment and molds. The processing and manufacturing of machine molds is very convenient, the manufacturing cycle is short and the cost is low. Theoretically, there is almost no upper limit on the size of parts formed by rotational molding process. It is impossible to produce such a large plastic container without expensive and huge blow molding equipment if blow molding is adopted.