Using special material (no nickel content) with a proprietary manufacturing process, KANTHAL APM material is very resistant to oxidation and gives superior hot strength. When heated above a certain temperature, very strong and uniform alumina layer will be formed at outer to protect the material from further oxidation.
As a result, when APM is used to manufacture Radiant Tube Heater and the Radiant Tube, it could give very long life with any bending or oxidation happening at the surface of the heater and the tube. Kanthal Tubothal and APM Tube, when used together, will give a minimum 3 times longer life than regular radiant tube heater set. Tubothal heating elements are available in standard dimensions from 68 to 170 mm (2.6 to 6.6 inch) diameter and can be supplied in almost any length. Tubothal elements can be used inside all types of radiant tubes or as stand-alone elements.