| 摘要 |
PURPOSE:To shorten an annealing time and to save energies with eliminating a difference in temp. between the top and bottom of a coil by detecting the temp. difference between the upper part and lower part of a coil and regulating the amount of circulating gas for heating according to the temp. difference thereof in a box type annealing furnace. CONSTITUTION:When a coil (x) is heated in a box type annealing furnace the temp. of the upper part and lower part of the coil is respectively measured by contact thermometers 1, 10 and the temp. difference is detected by a temp. difference detector 11. According to the temp. difference the number of revolutions of a motor 40 of a circulating fan 4 is controlled by a number of revolutions controlling unit 13 via a controllng unit 12 to regulate the amount of circulating gas sent to a plenum chamber 5. The temp. of the upper and lower parts of the coil (x) are thus lowered and the shortening of annealing time and the reduction of a fuel unit requirement are achieved. |
