General Aspects of Thermoforming

FIGURE 10.12 Typical pressure thermoforming process, (a) The clamped sheet is heated to the processing temperature by means of infrared heaters, (b) The heated sheet is removed from the radiation heating source and placed into position for forming, (c) Vacuum is applied to the underside of the sheet or air pressure is applied to the top side of the sheet, forcing the heated sheet into the mold. 

FIGURE 10.13 Forming in a matched metal die system. After heating, the sheet is formed by the application of mechanical pressure to the upper part of the mold. 

FIGURE 10.14 Twin sheet thermoforming process, (a) Heated sheets are placed between the mold halves, (b) The mold is closed, sealing the two sheets at the edges and around an inflation tube. (c) Air pressure is supplied through the tube, causing the sheets to inflate against the mold walls, (d) The mold is opened once the sheets are cooled and the part is removed. 

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