| 摘要 |
PURPOSE:To sharply decrease the rust generation, by using washing water mixed the water repellant at the time of washing by water in the pickling process of metal strip. CONSTITUTION:Cl', SO4'' etc. stuck on the metal strip in pickling process, are decreased by using washing water mixed the water repellant at washing time and rust generation is prevented. For example, already-known silicon compound, fluorine compound etc. are usd as the water repellant and in case of using silicone water repellant, about 0.01% said repellant is mixed. For example, scale of the hot-rolled steel strip 1 is crushed by the scale breaker 2 and is pickled in the first acid tank 3 and the second acid tank 4 and then, is washed by hot water in the hot water washing tank 5. Said strip is washed by water by providing the water repellant mixed washing water jetting apparatus 9 between the hot spray 6 and the squeeze roll 7. Hereby, amount of water stuck on the surface after passing through the roll 7, is reduced to <=1/10 and also, stuck amount of Cl', SO4'' is reduced to <=1/10. |
