Hydraulic Press Machine for Warm Extrusion

Extrusion is the process of forcing materials to produce plastic deformation through a gap between the die or the die outlet and the punch. Warm extrusion is one of the popular types of extrusion widely used in the market. As the name suggests, this forming technique works on material, metal blank, which is heated above the room temperature but lower than the crystallization point. By heating the metal blank, the resistance of the billet is significantly decreased hence making it easy to deform and form the required shape.

Warm extrusion is a push-through compressive forming process that uses an extruder. In the process, the heated metal blank is placed against the die. Then, force is applied on the punch to pressure the blank to form the product. The tonnage applied on the punch is determined by several factors, with the type of material being the main one. The good thing is that modern extruding machines enable you to calculate and select the tonnage automatically.

There are various types of warm extrusions that you can select from depending on the kind of parts you want to manufacture. However, the most widely used are forward, backward and compound extrusions. In the forward extrusion, also known as direct extrusion, the billet or the material being extruded flows in the same direction as the punch. In this process, the die has an orifice where the material is forced to pass to produce the required product. Forward extrusion produces hollow and solid parts, such as rods and tubes.

In backward extrusion, also known as the indirect extrusion, the material being extruded moves in the opposite direction of the punch movement. In the case, the work-piece is kept in a completely closed chamber on one side, and the extrusion dies are placed on the punch. The punch kept hollow so that the extruded section of the work-piece can travel through it. This process can produce both square and cylindrical shapes that are closed at one end such as aerosol cans, food, and drink cans and other similar containers

In compound extrusion, part of the extruded material flows in the same direction as the punch while the other part flows in the opposite direction. It’s more of a combination of direct and indirect extrusion. It’s a great option for producing barrel parts, rods, cups, and any other product that the other two techniques can produce. Other warm extrusion processes that are also used include radial or lateral extrusion and forging.

Unlike cold extrusion, warm extrusion is usually used when there is a need for a proper balance between the required forces – that is, ductility and the final extrusion properties. There are also many advantages that warm extrusion increasingly popular with manufacturers. This technique of forming is fast and offers incredibly high volume production. The strength of the parts is incredibly high hence good durability. The surface finishing is excellent. However, you might need heat treatment to polish the product.

Another advantage is that warm extrusion is working with a vast range of metals. Some of the metals that can be warm extruded include magnesium, lead, tin, aluminum, nickel, copper, zinc and their alloys, stainless steel, low carbon steel, tool steel, low alloy steel, medium carbon steel, and their alloys among many others.

Warm extrusion is good for mass production and can be used to produce a vast range of parts. Some of the products that can be manufactured using this extrusion include collapsible tubes, shock absorber cylinders fire extinguisher cases, shock absorber cylinders, rods, tubes, aluminum cans, barrel parts, gear blanks, gas bottles, mining equipment, light poles, hardware joints, straight cylinders and so on.