Extrusion is a process that is developed at an industrial level.
Extrusion is the act and result of extruding . This verb ( extrude ), in turn, is used to refer to the action of giving shape to a certain mass through its passage through an opening with a particular design .
It is interesting to review the etymology of extrude to learn more about this concept. Its origin is found in the Latin word extrudĕre , which according to the dictionary of the Royal Spanish Academy ( RAE ) can be translated as throwing or throwing out with violence .
What is extrusion?
Extrusion is a process that can be carried out in different ways and with different materials. At a general level, the procedure is used in industry to create parts with a fixed cross section .
To carry out extrusion, the material in question is pushed through a mold or die . Extrusion can be semi-continuous or continuous and can be carried out with the material cold or hot.
Metals , ceramics and plastics are some of the materials that can be extruded. If we focus on metals, we can mention the extrusion of aluminum to create bars, the extrusion of zinc for the manufacture of tubes, the extrusion of tin for the production of pipes and the extrusion of copper to obtain wire, for example.
With metal extrusion it is possible to obtain multiple products.
The case of polymers
As for polymers , extrusion is a molding that takes place, with pressure and thrust, by continuous flow. Typically, the polymer is melted and, thanks to the thrust provided by an Archimedean screw or spindle that rotates in a chamber or barrel , it passes through a head or die that gives it the desired shape.
A hopper is responsible for feeding the machinery, providing the polymer. The casting of most polymers, meanwhile, is achieved by combining the high temperature of the barrel with the mechanical cutting and dragging action that generates friction.
food extrusion
The extrusion technique is also used in the food industry . In this area, its purpose is the production of foods with certain organoleptic characteristics that make them more attractive or innovative.
Thanks to extrusion, it is possible to create novel shapes and new textures. It is usually used to produce breakfast cereals , children's cookies and snacks, among other options.
The notion in geology
In the field of geology , the eruption of magma on the Earth 's surface is called extrusion. It should be remembered that magma is an igneous mass that is melting and remains inside the Earth's crust; When it emerges, it is called extrusion.
Extrusion, on the other hand, allows the appearance of extrusive rocks, effusive rocks or volcanic rocks . These rocks are born when, after the eruption of a volcano, the magma comes into contact with the atmosphere and crystallizes due to cooling.
Basalt is the most common extrusive rock . Other rocks of this type are dacite , rhyolite and andesite .