Radiant tubes are mostly used in continuous retreat, galvanizing line horizontal annealing furnaces and silicon steel heat treatment furnaces. Under the nitrogen and hydrogen protective atmosphere, natural gas or coke oven gas is burned in the tube to provide heat energy. The steel is rapidly and uniformly heated from normal temperature to about 900 degrees, and the strip is annealed.
      The straight section of the radiant tube adopts high temperature resistant centrifugal casting tube, the elbow adopts the precision casting process, and the material is high nickel-chromium alloy cast steel, such as 2.4879, 1.4852, ZG45Ni48Cr28W5Si2, MORE1, MORE2, the flange is forged and machined, and the highest use The temperature can reach 1200 degrees, and it can work for a long time at 800 ℃ ~ 1200 ℃.
  The main detection methods of radiant tubes are: material composition detection, PT, RT flaw detection, water pressure detection, size detection, appearance detection, etc.
Radiant tubes are widely used and are often used in the following occasions:
(1) Heat treatment with protective atmosphere.​​
(2) It is required that the temperature distribution in the furnace is fairly uniform and the heating and cooling temperatures can be arbitrarily given. 
(3) The material is separated from the combustion gas and water for heating, and the number of air changes is large, which is beneficial to radiation heating.​​
(4) It is used for heating liquid and as a heat source for salt melting furnace.​​
(5) Occasions requiring low operating cost, high efficiency and low noise.​​
(6) For heating slender members and requiring a small number of burners, such as roller furnaces, small push-steel furnaces, etc.