| 摘要 |
PURPOSE:To provide a metal hot dipping device which can afford the whole of heat sources necessary for gas wiping with waste gases of combustion by subjecting the air to be fed from the outside to gas wiping nozzles to heat exchanging with the waste gases of combustion that heat an outside heating type metal hot dipping bath. CONSTITUTION:A steel strip S is introduced continuously into an outside heat type metal plating bath (consisting of a lead bath 3 of an outside cell 2 and a zinc bath 5 of an inside cell 4) with a combustion furnace, and is delivered out in a vertical direction, whereby it is wiped with gases. Here, the air to be introduced at 13 from the outside to gas wipping nozzles 8 is subjected to heat exchanging with a heat exchanger 9 provided in a flue 1b to a suitable temp., for example, in a 150-400 deg.C range. This air is fed by pressure to the nozzles 8 through which it is ejected. By this ejected air, the thicknesses of the plating on both front and rear surfaces of the strip S right after the excess zinc is squeezed off with squeezing rolls 7 after the passage through the bath 4 is controlled. Since the indirectly heated air is used for the wiping gas, troubles owing to the presence of dust, mists, etc. that may be caued by the direct injection of the gases formed by combustion are prevented. |
