Aluminum can be shaped in a variety of ways, but all of the methods involve a die or a mold. In extrusion, a metal billet is heated, pushed through a die to create a desired shape, and then cooled. Drawn aluminum is also heated, pushed through a die, and then forced through a second die or mold, undergoing what is called cold drawing or cold working. This is where the final dimensions of the tubing are determined. The drawn tube process can take from 5 to 10 operations to yield a 5mm tube.
Drawn tubing is ideal for applications that require tight tolerances, thin walls, high structural integrity and predictable performance under pressure.
Aluminum Tube Shapes
Aluminum tubes are widely used and available in round, rectangular and square shapes. The strength is a factor of the aluminum alloy used, the thickness of the walls, and the size of the tube. Tubes of larger diameters can withstand less stress and pressure.
- Round aluminum tubes
Round tubes are available in the widest variety of sizes, from an outer diameter of 5/8 inch to 16 inches and wall thicknesses of 1/16 inch to 1 inch. They are produced in several different alloys, each with unique properties. 6061-T6 is most common due to its overall structural strength and toughness, nice surface finish, good corrosion resistance to atmosphere and sea water, excellent machinability, weldability and joinability. Used extensively in the manufacture of marine and automotive components, round tubes play a major role in a wide variety of construction projects.
- Square aluminum tubes
Square tubes feature defined square corners on both the inside and outside radii, but are available in a more limited range of sizes than round tube. They are well-suited to structural applications that need light weight material. Wall sizes range from 1/8 inch for smaller tubes to ½ inch for larger ones, and they are typically made from 6061 and 6063 alloys. 6063 aluminum square tubing is the lower-strength choice but offers better corrosion resistance and superior finishing qualities than 6061. 6063 square tubing is easy to weld, cut and machine, so it is frequently used in gates, handrails, frame work, support columns, protective barriers and fencing. The greater strength of 6061 square tubing makes it ideal for structural applications.
- Rectangular aluminum tubes
Rectangular tubes have square defined corners on both the inside radius and outside radius, and generally range in size from 1/2 inch to 8 inches per side. Their wall thickness ranges from 1/8 inch to 1/2 inch. Typically made from 6061 and 6063 alloy, 6063 rectangular tubing is easy to weld, cut and machine, and its superior finishing qualities make it an excellent choice for architectural trim, door and window frames, furniture components and trim, safety and deck structures, athletic equipment, fencing and support columns. 6061 rectangular tubes are widely used for projects where light weight and corrosion resistance is a major concern.
Hydro’s nationwide network of 20+ locations and more than 60 extrusion presses gives us extraordinary capabilities in extruded aluminum shapes, sizes, alloys and tempers, including both direct and indirect extrusion methods.