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| Extrusion & Conversion |
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What is it? The process of squeezing toothpaste from its tube is one of extrusion. The gooey toothpaste - or the gooey polymer or metal in the industrial process - is forced by pressure to flow through a shaped die, taking up the profile of the die orifice. In co-extrusion two materials are extruded at the same time and bond together - a trick used in toothpaste to create coloured stripes in it.
Design Notes Polymer extrusion begins with powder or pellets; pressure is built up by a rotating screw, forcing the polymer through a heating chamber and through the die. Most polymers can be extruded (including those with particulate and short fibre-reinforcement).
The Environment No special problems here. |
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