| 摘要 |
PURPOSE:To reduce thermal stress when temperature distribution of a rotary shaft is controlled by heating an internal side of the hollow rotary shaft, by inserting axially divided heating materials in the shaft and controllably heating said heating material in such a manner as to eliminate the thermal stress due to a difference between internal and external temperatures of the shaft. CONSTITUTION:A heating material supporter 5 accommodating axially divided heating materials 8 in an outer shell 6 consisting of heat conductive material is inserted and set in a hollow rotor 2 of a steam turbine 1, and electric conduction of a current in the material 8 is controlled by a controller 9. A temperature sensing element is set to an external surface of the shell 6, and a rotor internal surface temperature signal 14 is input to an axially directional temperature difference distribution calculating unit 18 together with a rotor external surface temperature signal 15 through internal and external surface each temperature distribution calculating units 19, 16. Then an output of said calculating unit 18 is input to a thermal stress distribution calculating unit 22 to obtain thermal stress and compare the stress with a permissible value 26 in a comparator 24, in accordance with the deviation, the heating material 8 is controlled through a heating control unit 28. |
