extrudere

Extrudere is a Latin verb meaning to thrust out or push forth. It comes from ex- meaning out and trudere meaning to thrust or push, and it is the linguistic root of the English words extrude and extrusion. In classical Latin, extrudere described the act of forcing matter out of a container or surface. The modern terms extrusion, extrude, and extruder are derived from this verb.

In engineering and manufacturing, extrusion is a shaping process in which a material is forced through a die with a fixed cross-section to create objects of uniform profile along their length. The method is used with metals, plastics, ceramics, and some foods. Materials may be heated for easier flow in hot extrusion or processed at or near room temperature in cold extrusion. Variations include direct and indirect extrusion, as well as hydrostatic extrusion and powder extrusion, which change the pressure path or the state of the material.

Equipment for extrusion typically includes a container, a ram or screw to push the material, and a die at the exit. Plastic parts are commonly produced with screw-driven extruders, while metals may use ram presses or hydraulic systems. After extrusion, products can be cut to length, sized, quenched, or aged as required.

Applications are diverse: metal profiles for construction and transportation, tubes and pipes, automotive components, plastic profiles, ceramic parts, and food products such as pasta and snack shapes produced by forcing dough or dough-like mixtures through dies.

See also extruder, extrusion process, die.