Cold Drawn Tubing Is Superior to Extrusion

There are two types of tubing processes: cold drawing and extrusion

In the extrusion process, the aluminum billet is heated to at least 8OO°, pushed through a die, then flooded with cool air. This drastic temperature change causes the shape to react with non-symmetrical, shrinkage and the sidewall to belly in.

At A-Alpha Waveguide, we utilize a superior process of cold drawing, in which the tubing is pulled through a hardened steel die at room temperature, allowing for very close tolerances and a higher quality product.

Cold drawing has 2 major benefits:

  • The grain structure of the material is refined, creating a uniform composition.
  • The dimensions are firmly set. At room temperature, there is no heat related contraction to affect dimensions.

Ultimate care and control are maintained
during the cold drawing process.

This process is similar to coining a dime, where the raw blank is struck heavily and the metal takes on the exact shape of the coining die. Cold drawing allows us to flawlessly hold the shape and the tolerances each time. The fine grain structure has many advantages as well: the tube is more malleable and can be flanged, pierced or formed more radically without splitting. This process also induces fewer internal stresses and the tubing is therefore affected far less by any stress relieving function, such as asymmetrical machining or piercing. This characteristic saves money since other methods require reworking parts after fabrication to meet the drawing specifications.