| 摘要 |
PURPOSE:To cast a beautiful ingot of less surface flaws efficiently by comparing the measured stress value of the side walls of a mold and its fluctuation values with a preset critical distortion value and critical distortion fluctuation value, and controlling casting operation conditions. CONSTITUTION:A strain gage 3 having the coefft. of thermal expansion equal to the coefft. of thermal expansion of the side wall 1 of a mold is fitted on the rear surface of the wall 1 made of copper in contact with a cooling box. A lead wire 4 fitted to the gage 3 is led out to the outside through a pipe 5 made of stainless steel and is connected to a bridge box 6. The measured value measured with the gage 3 is passed through a dynamic strain gage amplifier 7 and a scanner 8 via a bridge box 6, and is converted to a digital signal with a digital voltmeter 9 and this is inputted to a computer 10. While the computer 10 calculates the magnitude of the quantity of distortion and the distortion fluctuation value during steady casting, it is inputted with the preset critical distortion quantity and critical distortion fluctuation quantity from a storage device 11 and compares both of them. The result thereof is stored with a printer 12, and is outputted as an alarm signal from an alarm device 13. |
