TEMPERING APPARATUS

PURPOSE:To provide a tempering apparatus capable of being prevented in tempering stress by a simple installation and a process, constituted from such a mechanism that means for holding, rotating, heating, cooling, pressing and correcting a material are provided and a tempering and an aus-forming processes are assembled in a series of processes. CONSTITUTION:A tempering material 1 such as a rack bar is heated to about 840-920 deg.C by a work coil 3 while held and rotated by a rotary holder 2 to be held for a definite time. In the next step, the work coil 3 is retracted and the material 1 is quenched to about 550-600 deg.C by injecting a cooling liquid from cooling press dies 4, 4. At this temp., the injection of the cooling liquid and the rotation of the holder 2 are stopped and the material 1 is brought into close contact with the dies 4, 4 and pressed thereby. After this material is pressed and corrected at a temp., up to about 450 deg.C, pressure is released while the injection of the cooling liquid and the rotation of the holder 2 is reopened to quench the material 1 to about 150 deg.C or less and the material 1 undergoing a tempering process is detached from the holder 2.