GB779669A - Improvements in or relating to radiant heating tubes for industrial furnaces - Google Patents

Abstract

779,669. Radiant tubes for furnaces. NASSHEUER, J., NASSHEUER, A., and HOPFNER, [nee NASSHEUER], M. Nov. 24, 1954, [No. 34128/54]. Class 51 (1). A radiant heating tube comprises a jacket tube closed at one end and having a waste gas outlet near the other end, a burner tube extending axially into the jacket tube, its inner end being closed and holes being formed in the wall of the burner tube between the end of an axial fuel inlet and the inner end of the burner, so that gas passing through the holes and burning in the jacket preheats air supplied at the outer end of the burner tube. The radiant heating tube comprises an outer jacket 1 closed at the furnace end and set into the furnace brickwork. A fluepipe is connected to a branch 4 near the outer end, which is closed by a cover 6 carrying a flame tube 7 to which air and gas are supplied through a connection 13 and a pipe 10 respectively. The gas pipe 10 extends to a nozzle brick 11 within the flame tube 7, which forms a burner tube 8 beyond the nozzle 11. The burner tube 8 is pierced by holes 23 and closed at its head end, so that gases partially burnt in the tube 8 pass through the holes and combustion is completed as they pass through the jacket 1 to the flue connection 4, heating the incoming air in the flame tube 7. The burner tube 8 may be of constant cross-section, or have a truncated conical part between the nozzle and a cylindrical part of reduced cross-section. The spacing and size of the holes 23 may vary along the length of the burner tube 8 to give a desired temperature distribution along the jacket 1. In a modification, Fig. 8, the jacket 1 is of inverted pear-shaped section, and an aperture 19 is provided in the cover 6, Fig. 6, to allow the removal of soot collected in the bottom groove. A transparent cover 20 closes the aperture 19, and acts as an observation window. A scraper may be provided to clear the window 20.