Melting compression

The main component of the reciprocating screw injection molding machine. It may have various sizes, lengths, and compression ratios. It is used to feed, compress, melt, and meter the resin for injecting into the mold cavity. Basically divided into 3 major sections feed section, deep screw depths to convey the resin into the next screw s section transition section, gradually decreasing screw depths when resin is compressed, forced against the barrel s surface, and melts and... 

Extrusion is the process where a solid plastic, usually in the form of beads or pallets, is continuously fed to a heated chamber and carried along by a feed screw within. As the solid resin is conveyed, it is compressed, melted and forced out of the chamber through a die. Through the cooling process the melt part results in a resolidification of the resin... 

In the case of biocomposites, the basic extruder equipment works in a similar way or has few supported modifications. Generally, the bead or pallets of the thermoplastic resin are mixed together with 30 to 40% of short/long natural fibers, compressed, melted (wherein the natural fibers are impregnated with resin) and forced out through a die. The equipment which had supported modifications is intended to create raw materials for the injector. 

The reciprocating screw is used to compress, melt, and convey the material (similar to the extruder screw). The difference is that ... 

There has been a general trend to move the Maddock element out of the compression/ melting zone and re-position it in the metering section or sometimes at the screw tip. 

Completion of melting of the solids bed moves towards and beyond the end of the compression/melting zone as screw speed is increased. It may even result in incomplete melting at the screw tip and lumpy extrusions. 

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