Radiation tube is through the gas in the radiation tube combustion, the use of heated casing surface in the form of heat radiation to transfer heat to strip steel, strip steel heating to the required annealing temperature.

At present, the radiation tube develops rapidly and has many kinds, such as straight tube casing, U type W type P type 0 type, etc., among which the U type radiation tube and W type radiation tube with waste heat recovery device are widely used.