| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a method of preventing biased heat of a billet by suppressing lowering of a temperature of the billet near a discharge port by a simple method without remodeling equipment. <P>SOLUTION: In this method of heating by a rotary furnace used as a heating furnace for an element pipe as a material of manufacturing a seamless steel pipe, the billet 9 near the discharge port 3 is heated by using the door burner 6 disposed on a place closest to a soaking zone side from the discharge port 3 of the rotary hearth-type heating furnace 1, and the door burners 6 disposed on an outer furnace wall 2a and an inner furnace wall 2a as fixed furnace walls of the rotary hearth-type heating furnace 1. The billet 9 is discharged from the rotary hearth-type heating furnace 1 to measure its temperature, the measured temperature is recorded on a temperature chart, and the billet 9 is heated while increasing an opening of heavy oil of the door burners 6 when the lowering of the temperature of the billet 9 is confirmed from the recorded temperature chart, so that the temperature of the billet 9 discharged from the rotary hearth-type heating furnace 1 reaches a prescribed temperature. <P>COPYRIGHT: (C)2012,JPO&INPIT |
