Thermoforming production mold materials

Thermoforming results in characteristic thickness distributions of the part s walls. Once the sheet contacts the mold surface, it sticks and locally cools. The wall thickness distributions are due to hindering and stretching of the hot sheet material. Thermoformed sheet once formed as product is cooled below its softening to freeze is normally performed by conduction via the mold surface. The mold is kept at a constant temperature by cooling or heating. Finally, the thermoformed product is demolded and cut out or trimmed by various means around the formed regions. 

The thermoforming mold is usually single-surfaced. Aluminum is the preferred material for longer production runs for both thin- and thick-gauge thermoformers. The mold serves several purposes and has several requirements. 

Although some molding techniques are adaptable to the production of thermoset materials, thermoforming is carried out using thermoplastic materials. 

Leading the processing growth was the expansion of twin-sheet and pressure-formed plastic products. Fueled mostly by advances in mold technology, material developments, and thermoforming machinery capabilities, technology improvements in the form of machine controls have led to machine designs that are faster and more consistent than was previously possible. As an example advanced materials and... 

This is another version of cold forming by utilizing a thermoformed plastic skin to impart an excellent surface and other characteristics (for weather resistance, etc.) to a cold-molded RP. For example, a TP sheet is placed in a matched mold cavity with an RP uncured material placed against the sheet. The mold is closed and the fast, room temperature curing plastic system hardens. The finished product has a smooth TP-formed sheet backed-up with RP. 

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