Custom Electric Manufacturing Co.

The APM tubes, developed by Kanthal Corp., are extruded from a 22% Cr, 4-6% Ni, 72-74% Fe alloy based on the same composition used to produce high-temperature Kanthal APM heating element wire. When heated, APM tubes form a self-regenerating aluminum oxide layer on inside and outside surfaces, resulting in resistance to thermal and mechanical shock, spalling, scaling, carburization and creep deformation. Other advantages of the APM tubes include form stability for higher temperature operation, low density for weight reduction and easier mounting, extruded construction with no welds to fail, excellent performance in corrosive atmospheres and no spalling to contaminate heating elements and workloads.