ekstrusi

Ekstrusi is a manufacturing process in which material is forced through a shaped die to produce objects with a uniform cross-section. The method is used for metals, polymers, ceramics, and some foods. Variants include direct (forward) extrusion and indirect extrusion, as well as hot (warm) and cold extrusion. In direct extrusion a ram or screw pushes the material through the die; in indirect extrusion the die is stationary and the container moves, reducing friction. Hollow profiles are produced with a mandrel.

The process typically involves preparing a billet or feedstock, heating it to the appropriate temperature if required, forcing it through the die, and then cooling and cutting the extruded length to size. Equipment ranges from small laboratory presses to large industrial hydraulic presses and screw-type extruders. Die design and surface finish are important, since friction, temperature, and material properties influence flow and quality.

Common applications include aluminum structural and architectural profiles, plastic tubing and window profiles, and polymer sheets in some cases. In food processing, extrusion forms products such as pasta shapes and snacks by forcing dough through a shaped die and then cutting or expanding the extrudate.

Advantages of ekstrusi include the ability to produce long parts with complex cross-sections, good dimensional control, material efficiency, and near-net-shape capability. Limitations include high equipment and tooling costs, material flow constraints, and potential defects such as surface cracking, voids, or wrinkling if process conditions are not properly controlled.