| 摘要 |
PURPOSE:To shorten the annealing time and to reduce the energy cost, by placing pipes filled with inactive gas and electric heaters in inclined annealing furnace side by side and heating the above pipes with electric heat and combustion heat passing the wire rods through the pipes. CONSTITUTION:Fuel and air mixed in the mixer 13, are ignited at burner 9 and combustion gas is blown in the inclined annealing furnace 1. The air 4 heated in the furnace, is moved to the upper part of the pipes group 2 by convection and the group 2 is heated along the total length from the upper and lower sides by the air 4 together with radiant heat of the electric heater 3 arranged at the furnace bottom. On this occasion, a slight temperature control in the furnace is made possible by carrying out ON-OFF control of the heater 3. Exhaust gas is sent to the heat exchanger 14, 15 and the wire rod 7 drawn out from the pipe, is cooled introducing the warm water 21 to the outlet of the furnace and then, oxidation of the wire rod is prevented by intercepting the outside air passing the steam 22 through the pipe. |
