What's the plastic extrusoin? How it works?
Plastic extrusion process How it works?Advantage / DisadvantagePlastic profile extrusion is a molding method in which plastic resin is continuously melted, pushed through a die with the desired cross-section (a “profile”), and then pulled through a water bath until fully cooled. The formed plastic can then be fabricated and either cut into multiple parts or wound as a single part.There are four zones through which the material moves through:• Extruding zone, in which resin is melted, additives such as talc, foaming agents, glass, or color may be added, and the material is forced through the extruder die assembly. • Sizing zone, in which a pull vacuum is used to prevent collapse and control warpage as the plastic hardens. This step is only used in profiles with one or more hollows.• Cooling zone, in which the plastic is ran through cool water tanks until it hardens completely.• Processing zone, in which the extrusion is measured for quality and processed in-line with the application of adhesion promoters, tape, slip coating, and/or ink-jet printing. This step is optional.• Cutting zone, in which the extrusion is cut to desired lengths or spooled.Compared to other forming and molding processes, extrusion has a number of advantages and disadvantages:ADVANTAGES•High production rates•Low cost tooling•Short tooling lead times•Many types of raw materials•Lowest cost conversion processes for plastics•Can combine multiple durometers in a single extrusionDISADVANTAGES•Only provides a uniform cross sectional shape•Surface area is not class A for all materials•Tolerances are greater than injection moldSecondary operations required to add a third