Rotational molding is also known as spin molding, rotational molding, rotational molding, rotary casting, rotary molding, and the like. In the rotational molding process, the plastic raw material is first added into the mold, and then the mold is continuously rotated and heated along the two vertical axes, so that the plastic raw materials in the mold are gradually uniformly coated and melted and adhered under the action of gravity and heat. The entire surface of the cavity is formed into a desired shape, and then cooled, shaped, demolded, and finally obtained.

The characteristics of the rotomolding process are mainly:

1. Low cost of rotomolding molds - For products of the same size and size, the cost of rotomolding molds is about 1/3 to 1/4 of the cost of blow molding and injection molding, which is suitable for forming large plastic products;

2. The edge strength of the rotomolded product is good. Rotomolding can achieve a thickness of more than 5 mm at the edge of the product, completely solving the problem of thinner edges of the hollow product;

3, rotomolding can be placed in various inserts;

4, the shape of the rotomolded product can be very complicated, and the thickness can exceed 5 mm;

5, rotomolding can produce fully enclosed products;

6. Rotomolding products can be filled with foaming materials to achieve heat preservation;

7. No need to adjust the mold, the wall thickness of the rotomolded product can be adjusted freely (more than 2mm). [1]

 Disadvantage

Rotational molding also has its shortcomings: the material has to be ground and pulverized, the cost is increased; the processing cycle is long, so it is not suitable for mass production; the available plastics are less; the opening and closing mold is a relatively heavy manual labor.

main application

Rotomolded products can be used in transportation, transportation safety facilities, entertainment industry, river channel dredging, construction, water treatment, medicine and food, electronics, chemical, aquaculture, textile printing and dyeing industries.

1, container type rotomolded parts

These plastic parts are widely used in storage and supply tanks, water storage tanks, various industrial chemical storage and transportation containers, such as acid, alkali, salt, chemical fertilizers, pesticide storage tanks, chemical companies, industrial coatings, rare earths. Washing tanks, reaction tanks, turnover boxes, garbage bins, septic tanks, living water tanks, etc.

2. Rotomolding parts for transportation

Mainly using polyethylene and polyvinyl chloride paste resin, rotomolding various automotive parts, such as air conditioning elbows, vortex tubes, backrests, handrails, fuel tanks, fenders, door frames and shift lever covers, battery housings, snowmobiles And the fuel tank of the motorcycle, the aircraft fuel tank, the yacht and its water tank, the boat and the shock absorber between the ship and the dock.

3. Rolling plastic parts for sports equipment, toys and handicrafts

There are mainly various kinds of parts of PVC paste rotomolding, such as water polo, floating ball, small swimming pool, entertainment boat and its water tank, bicycle seat cushion, rotomolding pallet, surfboard and so on. Toys such as pony, dolls, toy sandboxes, mannequin models, crafts, etc.

4, all kinds of large or non-standard rotomolded parts

Shelf, machine casing, protective cover, lampshade, agricultural sprayer, furniture, canoe, camping vehicle canopy, playground equipment, planter, bathroom, toilet, telephone room, advertising display board, chair, highway isolation pier, traffic cone , river buoys, anti-collision barrels and building construction barriers, etc.