Aluminum Extruded Tubing
Aluminum extruded tubing is a hollow linear aluminum product that is typically cylindrical, however aluminum square tubing and aluminum rectangular tubing is also manufactured for specialty applications such as aluminum downspouts and building supplies. Aluminum tubing may also have rectangular, square or round cross-sections. Formed during extrusion processes, aluminum tubing may be hot extruded, cold extruded or warm extruded, all of which extrude aluminum through a die. Aluminum extruding tubing has a wide range of applications such as mining equipment, hardware joints, fluid and gas transport, light building frames, structural applications, lighting fixtures and light poles. In addition, aluminum tubing has high electrical conductivity and is a good heat conductor and reflector, making it ideal for heat transfer and heat shield applications. Industries that benefit from aluminum tubing's flexibility and high strength-to-weight ratio include construction, industrial manufacturing, medical, aerospace, automotive, petrochemical and food processing.
Aluminum tubing is formed during the extrusion process, in which round aluminum stock called "billets" or "logs" are pressed by a ram through a die, which is a hollow profile that shapes the aluminum into a specific extruded shape as the billet is squeezed through. Extrusion processes include hot extrusion, cold extrusion and warm extrusion. In cold extruding, aluminum billet is pressed through the die at room temperature or near room temperature. Warm extruding, or forging, is done on billets brought to temperature ranges between 800 and 1800 degrees F. Hot extrusions are performed on aluminum which has been fully plasticized by heat and is often performed in a vacuum to avoid oxidation. Aluminum can be extruded through the die using two different methods of extrusion: indirect extrusion and direct extrusion. Direct extrusion holds the die stationary while the ram forces the aluminum alloy through the die opening, while indirect extrusion holds the die stationary as the hollow ram moves into the stationary billet from one end, forcing the metal to flow through the die. After the aluminum tubing has been extruded, it is straightened by a stretcher.