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The mechanical plastic shell adopts the plastic thermoforming process, which is a method of making products under the high elastic state economy by using the sheet material of thermoplastic plastic as raw material. It has a lot of requirements on the material, the first to have a good heating elongation, high height and diameter ratio, good elongation.

Secondly, the mechanical plastic shell material should have high enough tensile strength, impact strength and pinhole resistance; Products with composite requirements shall have good thermal viscosity strength; And have good transparency and glossiness; Color printing requirements of products, corona processing can be carried out.

Hot forming is mainly used to produce thin shell products of different types and sizes, but they are generally simple shaped cups, plates, covers, medical utensils, medical instrument shells, instrument shells, mechanical plastic shells and other plastic shells and children's toys.

The wall thickness of the product is small, the sheet thickness is generally 1~2mm, or even thinner, the thickness of the product is smaller than this value. The area of the products can be very large, but hot - formed products are part of the shell, so its depth is limited. The selection of various plastic products depends on the performance requirements of the limited use of the products. Therefore, the principle of thermal forming material selection can only be used for thermal forming processing of plastic varieties.

All thermoplastics are suitable for thermoforming because they have in common the characteristic that the material's elastic modulus and ability to withstand loads rapidly declines under heating conditions. However, in practical application, it is necessary to consider the thermal properties, mechanical properties and aggregate structure of a material to determine whether it is suitable for thermal forming.