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Compared with other die process, rolling plastic process provides us with more design space. With the right design concept, we can combine several parts into a complete mold, which greatly reduces the high assembly cost.

The roll-molding process also includes a series of inherent design ways of thinking, such as how to harmonize the thickness of the side walls and how to strengthen the external Settings. Because each part in the manufacturing process is formed under high temperature and rotation process, unlike those parts formed under pressure, the rolling mold does not need to undergo special processing like injection molding process to withstand the test of heavy pressure.

Take rolling plastic water tank as an example, it is suitable for the production of multiple varieties, small batch of plastic products - because of the simple structure of the mold used for rotating molding, low price, so it is very convenient to change products. The additives added in the production process can effectively resist the invasion of climate, electrostatic interference and other external objective factors.

Cooling is an important stage to control the size and performance of rolling plastic products. The rapidly cooled products will warp and deform. The slow - cooled rolled plastic products have a good shape, but use a longer production time. So for rolling molding, controlling cooling time is an important part for shortening product quality and production time.

Compared with most other processing methods, the cooling rate of rolling products is slower. This makes clean materials such as polyethylene produce larger crystal structure, and at the same time increases the tensile strength, flexural strength and flexural modulus of the material, and reduces the impact rolling plastic fuel tank energy and elongation.

As a result of slow cooling, the product has higher density, lower impact strength, lower stress cracking resistance and higher embrittlement temperature. Low density POLYETHYLENE (LDPE) is less sensitive to cooling than high density POLYETHYLENE (HDPE) due to its low crystallinity. In addition, the mold material will also affect the cooling rate, especially the wall thickness of rolled plastic products will also affect the cooling rate.