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Design points of rotational molding products

Release Time:2021-10-08 01:35:33

The rotational molding process can produce many different types of hollow plastic products, but to make the products more suitable for the rotational molding process, it is necessary to design the rotational molding products to better meet the requirements of the rotational molding process, so that the rotational molding products can play their best effects in use. The following is the experience accumulated by the creative rotational molding equipment editor in the rotational molding industry over the years, hoping to help the rotational molding industry.

1. Does the design include deeper side depressions in the direction of product detachment. If so, they must be designed outside or as active inserts, which will increase the cost of the mold. Due to the shrinkage of plastic, some small depressions may not be considered. But it is necessary to know the extent of the depression without the need for additional molds.

2. How many mold blocks are there. Under standard circumstances, there are two molds, but if the design of the product is more complex, multiple molds may be required. This will affect the cost of the mold, the maintenance of the mold, and the individual cost of plastic products.

3. What surface treatment is required for the product, whether it is cast on the surface of the mold or machined on the cast mold. The degree of surface treatment not only has a significant impact on mold costs, but sometimes specific surface treatments can affect product demolding.

4. Is there an area on the product where resin flow is poor between two wall surfaces. What is the distance in this area. If the distance is long, the surface treatment of the mold here will be difficult and increase the cost. If it is very narrow, it is difficult or even impossible for the resin to flow into the cavity.

5. Is the rounded corner in the design large enough to allow the resin to flow freely to every part of the mold. What is the sufficient fillet radius

6. Whether to use inserts to attach other components to plastic products. What is the position of the inserts and whether they can maintain their state during the molding operation.

7. Where is the parting surface of the mold. Sometimes there may be differences between the aesthetic needs of the product and the actual requirements of mold production in terms of parting surface issues.

8. If the compressive strength of the product wall is required to be high, should reinforcement ribs be designed on the product; Kiss style; Structure.

9. The corners of rotational molded products should be designed as rounded corners, not sharp or right angles. The rounded corners facilitate the flow and forming of raw materials. The larger the rounded angle, the better the uniformity of the wall thickness of the corners and the better the forming.

10. When designing dimensions for rotational molding molds, attention should be paid. Generally speaking, the shrinkage of rotational molding products is around 3%. If rotational molding products require high dimensional accuracy, analysis and adjustment should be made based on raw material parameters, internal structure of the product, and shrinkage of mold materials.


  • Name:Mr. Ye
  • Tel:+8618136719595
  • Address:No. 68 Zhongxiang Road, Huangchengdun Industrial Park, Chunjiang Town, Xinbei District, Changzhou City