| 摘要 |
PURPOSE:To make it possible to manufacture a product of constant high quality, by installing partitioning boards to a vertical electric furnace so as to divide the furnace into not less than two chambers, and by varying the heat treating temp. for each part of shaft material by control units. CONSTITUTION:The inside of a vertical electric furnace is divided into three chambers by two partitioning boards 1, 1' which are perpendicular to the direction of the center axis of the furnace. The material for a forged steel shaft is placed over the three chambers, and each part of the material in each chamber requires different temp. Plural circuits, each comprising an electric power source 3, a program oscillator 4, and a secondary current controller (SCR), are arranged outside the electric furnace, and the SCR5 are operated by the signals of the program oscillators. Hence when the temp. required for every parts of the shaft material and the temps. required for every chambers are set to the program oscillators, every parts of the shaft material are heat treated at the required temps. |
