Aluminiumwerk Unna is your specialist for aluminium tubes. We produce these at our site in Unna using our extrusion presses in two different processes: seamless extrusion or porthole extrusion. You can easily distinguish between the two manufacturing processes: In seamless extrusion, the mandrel for the inner contour of the tube is attached to a piercing ram. In porthole extrusion, the mandrel is fixed to the die by means of supporting ribs.
Which manufacturing process we use depends on the alloy and the application. For example, aluminium tubes made of an alloy that is difficult to extrude can only be produced by the seamless extrusion process.
Many standards and specifications require subsequent cold drawing of the tubes. Here you will find all relevant specifications for extruded and drawn aluminium tubes.
You need short fixed lengths instead of long manufacturing sizes? No problem. In our cutting plant, we can cut short fixed lengths from our profiles. Most of the tubes in our range of dimensions can be surface finished. By grinding (outside diameter) or honing (inside diameter), we are able to produce the outer and inner surfaces to the desired quality.
See in this video how we manufacture aluminium tubes for a shock absorber:
The production of an aluminium tube