| 摘要 |
PURPOSE:To eliminate the need for intricate processes such as with conventional methods and form oxide films preventing deposition of plating metal continuously and inexpensively by spouting and blowing the specific rates of oxidative gas to the one side of the steel hoop activated in a reducing atmosphere. CONSTITUTION:A steel hoop 1 activated of its surfaces in a reducing atmosphere is blown with the oxidizing gas of a rate of spouting (0.1m/sec. or higher) faster than the speed (10m/min) of the steel hoop 1 being blown out from a blow-out nozzle 4 at the turn down roll part 2, whereby an even oxide film is formed only on one side. The oxidizing gas impinges upon the steel hoop 1 and oxidizes the one side of the steel hoop 1. This gas is exhausted together with the inert gas from a nozzle 6 through suction port 5. The steel hoop 1 is sent to the plating path through the snout part 3. The oxide film obtained in this way prevents deposition of plating metal, eliminates the need for conventional masking or the like, improves workability and reduces cost. |
