There are many ways metal can be worked to form a desired shape. You can anneal it, cast it, or even chase it depending on how quickly you want to produce results. When it comes to forming detailed cross-sections, however, the most popular method is extrusion, and it’s easy to understand why.
Continuous. Other methods will require multiple processes, such as formwork construction, melting, and curing to produce a tube. Whereas, extrusion can perform all of those processes continuously. When metal requires hot-working, it is hot-worked right before being fed into the die, and as soon as it comes out of the die, the output becomes almost ready for use.
High production. Because the process is continuous, production is also expected to be high. In effect, you can save tremendous amount of time and money in the long run. Plus, you can double or triple your income in a short span as opposed to the few days of work when you use a more complex metalworking method.
Low Cost. A simple process means fewer resources, and fewer resources means huge savings. Extrusion results in less cost per pound of produced material compared to that of other methods. However, you can offer your products for the same or even higher price than those of other methods since they are of similar if not better quality, which translates to more income.
Considerations for Extrusion
As simple and easy as it sounds, extrusion has its share of complexities. Many factors need to be considered in order to enact the right metal flow through the correct application of force and eventually to produce the desired extrusion.
Type of material. The whole process of extrusion will depend greatly on the type of material to be extruded. If the metal is hard, it has to be hot-worked. If it’s soft, it can be extruded at room temperature. It’s easier to determine if there’s a need for hot-working if the metal to be extruded is brass. This is because brass is classified into alpha (soft), alpha-beta (neither too soft nor too hard), and beta (hard).
Size of work piece. Extrusion is a process in which a work piece is forced to flow through a die. The size of the die will depend not just on the size of the extrusion but also on the size of the work piece itself. A larger opening for the die is necessary, or a bigger die for that matter, if you need to feed a large work piece.
Geometric cross section of extruded part. One of the greatest advantages of extrusion is that it allows for the manufacturing of tubes and machine parts with complicated and detailed cross-sections. But such a process doesn’t come easy. Proper balance of push and speed is needed to produce a smooth cross-section. Push too hard or too strong and the tiny details will not be achieved. Push too slowly and the metal may harden before it even gets fed into the die.
Temperature of work. Metals can either be hot-worked or cold-worked. When extruding metal, you have to determine whether there’s a need to heat the metal first based on its hardness and density. While hot-working means subjecting the metal to high temperature, cold-working doesn’t mean cooling it first. Rather, it means working the metal at room temperature.
Brass is a great material for making tubes and other pieces, and extrusion is arguably the best method to work it. It’s a good thing that there are manufacturers, such as Rotax Metals, that offer brass extrusion, as it means you don’t have to go lengths just to have one for your projects. If you’re looking for high-quality brass extrusions, make sure that you will turn to the right supplier.
Sources:
http://www.csuchico.edu/~jpgreene/itec142/m142_f09/tsld012.htm
