| 摘要 |
PROBLEM TO BE SOLVED: To suppress deterioration of furnace member and products by early detecting defects in a radiant tube and taking counter measure. SOLUTION: An evaporation preventing gas is supplied into a vacuum chamber 12 through a gas supplying source and a gas supplying pipe 44. Inner pressure of the vacuum chamber 12 is detected by means of a vacuum pressure sensor 38, and the pressure data are inputted to a control unit 40. Volume of the evaporation preventing gas supplied into the vacuum chamber 12 is measured by a flow meter 46, and the data are inputted into the control unit 40. The control unit 40 adjusts volume of the evaporation preventing gas so as to keep inner pressure of the vacuum chamber 12 to a predetermined level based on the pressure data from the vacuum pressure sensor 38, and emergency is detected when the flow data from the flow meter 46 becomes less than the abnormal flow set preliminarily.
|
