An Overview of Aluminum Extrusion

An Overview of Aluminum Extrusion

Aluminum extrusion is a process that uses powerful hydraulic presses to shape aluminum into long, solid profiles.aluminum extrusion It is a versatile method that allows for the production of products such as thermal and energy-efficient windows and doors, manifolds and lighting track equipment. Extrusion can be used to create complex shapes that would be impossible to manufacture using casting methods because of the limitations of aluminum's tensile strength and ductility. This article will provide an overview of the extrusion process, with particular emphasis on die design and material flow.

Before aluminum can be extruded it must first be formed into a rod, bar or sheet of the desired size and shape. To achieve this, the alloy is heated to a temperature between 800-925deg F, a level that makes it malleable enough for the die to shape it. This is an essential step as the exact temperature is critical to achieving the desired product qualities, such as hardness and finish.

The next step in the aluminum extrusion process is to load a billet, or block of solid aluminum, into a press. The press itself can exert a force of up to 15,000 tons. Once the billet is loaded into the die, it is mechanically transferred into the press and pressed by the hydraulic ram until the desired profile emerges from the die opening. The process can be either continuous, for long lengths of product, or semi-continuous, resulting in smaller sections.

A good way to visualize the aluminum extrusion process is by thinking of a tube of Play-Doh(r). The handle of the tube serves as the ram, the shape bar in the middle of the tube as the die, and the Play-Doh(r) as the soft aluminum billet. As the Play-Doh is pushed through the opening of the tube, it takes on the shape of the die, forming the desired extrusion profile.

Once the shape is formed, it is sheared off from the billet and transferred to a cooling table where it is quickly cooled through air, water sprays or baths. This step is vital for ensuring the quality of the finished product as it allows the aluminum to straighten and release internal stresses. It is also a vital process for reducing the likelihood of defects such as warping.

The most important factor in a successful aluminum extrusion is uniformity of the material flow. This is achieved by using techniques such as modifying die bearing lengths, adjusting land lengths and incorporating flow channels or feeders. Uniformity also improves the die life by minimizing the amount of turbulence, dead zones and other defects that can be produced. Regular inspections and maintenance are necessary to prolong die life.