| 摘要 |
PURPOSE:To obtain a galvanized ferrous metallic product having good toughness of a plating layer by subjecting the outside circumference of an iron material to hot dipping of a Zn-Al alloy and subjecting the outside circumference thereof to pure Zn hot dipping by passing the same through a pure Zn bath on the surface of which is applied with a flame. CONSTITUTION:An iron or steel wire 1 is subjected to degreasing 3 and pickling 4 and after the wire is passed through a flux tank 5 and a dryer 6, the wire is dipped in a Zn-Al alloy plating bath 9 contg. >=0.2% Al. The plated wire is pulled up through a squeezer 11 and a cooler 12 and is further passed through a flux tnak 7 and a dryer 8 and thereafter the wire is dipped in a pure Zn plating cell 13 and is pulled through a squeezer 15 and a cooler 16, by which a galvanized ferrous wire 17 is obtd. A flame 26 of a burner, etc. is directly applied on the surface of the pure Zn plating bath in this stage to heat the bath surface so that the Al intruded in the bath is preferentially oxidized and removed and the contamination of the pure Zn by Al is prevented. The galvanized metallic product is stably produced by the above-mentioned method. |
