The invention discloses a preheating device of a single-bar
heating furnace. A bottom frame and a preheating chamber arranged on the bottom frame are included. A plurality of
smoke circulation devicesare arranged in the preheating chamber. Each
smoke circulation device comprises an air guiding pipeline, a
backflow pipeline, a circulation wind wheel arranged in the air guiding pipeline and a firstdrive mechanism, wherein the air guiding pipeline and the
backflow pipeline are mutually connected, the
backflow pipeline is arranged on the lower side of the air guiding pipeline, a circulation preheating chamber is arranged below the circulation wind wheel, the bottom end of the circulation preheating chamber communicates with the backflow pipeline, an aluminum bar is arranged in the circulation preheating chamber, a backflow channel is formed by the circulation preheating chamber and the inner wall of the air guiding pipeline, the circulation wind wheel is used for extracting
smoke in thecirculation preheating chamber, and smoke enters the circulation preheating chamber through the backflow channel to form smoke cycle. Compared with the prior art, under multi-time flowing cycle of high-temperature smoke, the high-temperature smoke can effectively make contact with the aluminum bars in the preheating chamber for efficient preheating, the
staying time of the high-temperature smoke in the preheating chamber is prolonged, the
heat transfer efficiency of the high-temperature smoke in the preheating chamber is improved, and the effects of energy saving and emission reducing are achieved.