Tooling thermoforming

Thermoformed chassis and body panels are featured on the car. The products were made initially in the USA for assembly in China. The car will weigh less than 2000 lb (900 kg). Automotive Design Composites, Inc of San Antonio, TX, designed the vehicle to have body panels and trunk formed from coextruded sheet of ABS with an ASA cap layer that will hang on a pultruded composite frame. Ceramic tooling is used to thermoform plastic products. 

GMT can be preferred to SMC for small or medium runs in the automotive industry. For example, German fire-fighting equipment manufacturer Rosenbauer is using ther-moformed sheet (multilayer ABS/PMMA) instead of hand-laid GRP. The cost of a body panel can be cut by 30% if the number of parts - in Three-digit quantities - is sufficient to justify the investment in thermoforming tools. 

Thermoforming is the most commonly used method for volume production today [10]. In this method a special type of reinforcement that is already impregnated with a preforming powder is heated before it is clamped in a cold preforming tool [11], The most common type of reinforcement is continuous strand mat which is manufactured by e.g. Vetrotex and Owens Coming. 

Thermoforming station (pocket depth, pocket rupture) Forming head pressure and pressure distribution Cooling water supply for heated and cooled tools Vacuum exhaust system Empty hopper detector Fill control system... 

Polyethylene, polyvinyl chloride and polypropylene are easily worked utilizing ordinary wood or metal working hand and power tools. Being thermoplastic, these materials can be easily thermo-formed as well as cut, sawed, drilled and tapped. In the heat forming process, electric ovens are generally used which can maintain good thermal control. Of the three thermoplastics, polypropylene requires the more finite thermal control. Table III provides approximate time and temperature relationship required for thermoforming these three plastics. 

A blister pack consists of a rigid (cardboard or other) bottom liner and a sleeve of a transparent pol5Tner material. The sleeve can either reproduce the packed article contours (blister strip pack, Fig. 2.55b) or be of regular spherical shape (blister bubble pack. Fig. 2.55c). The sleeve is produced by thermoforming and is bonded to the bottom liner by welding. For the blister pack, commonly inhibited film materials and sheets up to 0.15-1.0 mm thick are used. Mainly small-size hardware and tools are packed by this method. The blister pack adds an attractive appearance to the goods, protects reliably against various effects and enables direct observation of the contents by customers. 

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