| 摘要 |
PURPOSE:To prevent uneven plating due to the clogging of a gas injection port with molten zinc by constituting a gas throttling device for blowing away excess molten zinc of a molten zinc plated steel strip of a rotatable external cylinder having the gas injection ports and an internal cylinder for supplying gas having a sealing member. CONSTITUTION:Excess molten zinc deposited on a zinc plated steel strip 3 coming out from a molten zinc plating bath 2 is blown away from both sides of the steel strip 3 with gas injection by a gas throttling device 1. The gas throttling device 1 is constituted of a circular external cylinder 5 having gas injection ports 8 and nozzles 9 which is rotatable in the circumferential direction, and of an internal cylinder 11 having at the inside a gas supply port 16 and a sealing member 17 on the opposite side. The pressurized gas supplied into the internal cylinder 11 is spouted from a nozzle 9 of the external cylinder 5 on the outer side to blow away excess molten zinc. When the port of the nozzle 9 is clogged by the deposition of molten zinc, the external cylinder 5 is turned to an angle of 180 deg. and the gas is injected from another new nozzle 9. In addition, the injection of the pressurized gas from the nozzle 9 not facing the steel strip 3 is prevented by the sealing member 17. |
