| 摘要 |
PURPOSE:To uniformly control the vapor deposition thickness in the widthwise direction of band steel by using a learning vapor deposition chamber pressure coefficient obtained from the actual and theoretical values of the Zn vapor deposition chamber pressure when the metallic vapor-deposited layer of Zn, etc., is formed on the surface of band steel by a continuous vacuum deposition device. CONSTITUTION:The band steel 1 is continuously transferred by a rolling roller 4 from (a) to (b) in a vapor deposition chamber 3, a molten Zn bath 6 in an evaporation vessel 5 is heated by a heater 9 and evaporated, and the obtained vapor is passed through a duct 8 provided with a shutter 11 and a film thickness distribution controlling plate 15 to vapor- deposit Zn on the surface of the band steel. The stability of the Zn deposition control system of the device is judged. When the system is stabilized, the actual data such as the deposition amt. and a line velocity are collected, the ratios of the actual vapor deposition chamber pressure PX obtained by the inverse calculation from the data to the theoretical vapor deposition chamber set pressure PO, namely the learning vapor deposition chamber pressure coefficient CP=PO/PX, are statistically processed into a data table stratified in accordance with the specifications of the band steel, and stored in an arithmetic unit 23. A vapor deposition pressure setting calculation equation is adjusted on a line by using the values of CP, and reflected on the succeeding pressure setting. The Zn vapor deposition amt. in the widthwise direction of the band steel is thus uniformized.
|
