Aluminum Tube-Making Machines

Extrusion: Hot and Cold

• Extrusion machines are available to perform both hot and cold extrusions. Though technically, the aluminum isn't usually being extruded in the common meaning of the word, where pressure pushes molten or semi-molten material through a keyway in the form of the desired shape. Most aluminum tube-making machines --- even those called extrusion machines --- actually employ roll-forming, or pressing the aluminum into shape. Functionally, they work like extrusions and some utilize heat to make the roll-forming process easier.

Press Forming

• Roll-forming is a type of press-forming; press-forming is a broader technique of forming metal through pressure. Where roll-forming squeezes metal through rollers or guides, press forms just squeeze the aluminum with great force. Similar processes like drop-forging stamp material very quickly instead of using hydraulic pressure, for example, to exert steady force. Press-forming is generally not used for extended lengths of tubing. But it is a viable technique for fixed, shorter lengths, open on one or both ends.

Spinning

• Spinning is a metal-forming process ideal for aluminum. It is similar to throwing pottery on on a potting wheel. A mechanical armature squeezes sheet aluminum against a plug --- the inside shape of the tube --- which creates a roll-forming process right at the intersection of plug, aluminum and armature.

Casting

• Detailed aluminum parts can be custom-cast in precision molds. Pieces of aluminum tubing can also be machine-cast in a high-production assembly where multiple, interchangeable molds are coated with mold release agents, sealed, poured, cooled, removed and then prepared for another production cycle. Casting aluminum --- like most fabrication techniques --- is usually a consideration of economics, decided based on whether it's cheaper to cast, machine or otherwise fabricate the specified tubing.