Combination heating method of flame furnace and induction heating furnace
In order to give full play to the advantages of the flame heating furnace and the induction heating furnace, the flame heating furnace and the induction heating furnace can be combined to form a heating production line, that is, the blank is heated to the Curie point temperature in the flame heating furnace, and then enters the induction heating furnace Continue to heat until the required heating temperature. The advantage of this combined heating method is that the blank is heated in a flame heating furnace in the low temperature stage, and the temperature difference is large, and the heating speed will be faster. Because it only requires heating to the Curie point temperature (750 ~ 800 ℃), the surface of the blank is oxidized very little , While the heating after 800℃ is carried out in an induction heating furnace, the heating speed is faster, the heating time is short, and the oxidation amount of the blank is reduced.
The heat energy required to heat the blank to 1250°C is 240kW • h/t. If the efficiency of induction heating is 65%, the unit power consumption of the blank heating is 370kW·h/t. When the blank is heated to 780T in the flame heating furnace, the absorbed heat energy is equivalent to 150kW h/t. The heating energy of the blank in the induction heating furnace from 780℃ to 1250℃ requires 90kW·h/t. At this time, the efficiency of induction heating About 60%, the unit power consumption of the blank heating is 150kW·h/t, which is of great significance to the technical transformation of the old plant. When the original blank forging is heated by a flame heating furnace, the heating time is long, the oxide scale of the blank is thicker, the quality of the forged product is poor, and the service life of the mold is not high. If the flame heating furnace is to be discarded, the induction heating is used Furnace replacement, calculated at a productivity of 1000kg/h, an intermediate frequency power supply of 500kW is required. If the flame heating furnace is retained and an induction heating furnace is added for joint heating, the power supply of the induction heating furnace can be reduced to 160-250kW, which makes full use of the original equipment, and exerts the advantages of induction heating, reducing the blank Oxidation loss during heating improves the service life of the mold and the quality of forged products.