CONTINUOUS HEAT HOLDING FURNACE FOR STEEL WIRE ROD

PURPOSE:To form, by a heat treatment, a wire rod having no variance in quality in a short time in the heat treating stage of a steel wire rod by feeding the wire rod into a continuous heat holding furnace, forming the wire rod into a coil shape by a coiler, and heating and holding to and at a prescribed temp. in a heat holding chamber then taking out the wire rod through a substituting chamber and a discharging chamber. CONSTITUTION:A steel wire rod W is un-coiled from a payoff reel 13, and is introduced by means of a guide pipe 13 through a high frequency heating furnace and a roll bender into a continuous heat holding furnace. Said wire rod is coiled on the outside circumference of a rotating coiler 21. When the coil attains a specified length, the coil falls from the coiler 21 onto a holder 31 underneath the same. The top end is cut with a cutter 38 to form an independent coil. The holder 31 is opened to drop the coil into a heat holding chamber 4 underneath the holder and the coil is heated and held for a specified time by gaseous DX of a high temp., etc. to spheroidize carbide of the texture of the wire rod and to improve ductility and toughness. A shutter 41 is then opened to drop the coil into a substituting chamber 5, where the coil is cooled by the gaseous N2 introduced therein and thereafter the coil is dropped into a discharging chamber 6 underneath the substituting chamber and the cooled coil is removed from a heat holding furnace 1.