Radiant tube heating device is mainly composed of the tube, burner and waste heat recovery unit, etc.The tube body is to release the fuel combustion heat radiation into the heated object of key components.Because its surface with direct contact with the combustion flame and high temperature flue gas, poor working conditions, easy to local burn, oxidation;If the larger temperature difference exists along the length of the tube direction, will produce larger thermal stress, at the same time the impact of airflow during burning, also can produce certain vibration.So the tube should have good heat resistance, high thermal conductivity, strong ability to resist high temperature oxidation, small thermal expansion coefficient, high structure strength, and good sealing performance, etc.Burner is the core of the radiant tube heating device, its control power, the temperature distribution of the radiant tube, thermal efficiency and service life.
as shown in figure 1.But because of the waste heat recovery unit USES a common wall between structure, heat recovery effect is not very ideal, air preheating temperature is only 200 ~ 300 ℃, flue gas waste heat recovery is only 30%.The thermal efficiency of conventional gas radiant tube heating device is difficult to break through 75%.