| 摘要 |
PURPOSE:To thinly and uniformly spread a chromate soln. having low viscosity on a strip at high speed by carrying out wet-on-wet spreading through plural passes by a restricted amt. of the soln. stuck per one pass with coating rolls rotating in the same direction as the traveling direction of the strip. CONSTITUTION:A chromate soln. is sprayed from feeders (b) on a galvanized strip (a) traveling in the direction of an arrow. The sprayed soln. is spread by rotating flat wringer rolls (c) lined with synthetic rubber in the same direction as the traveling direction of the strip (a). Second-step wringing is then carried out with rolls (d) placed within the range in which the chromate soln. on the strip (a) does not dry. The amt. of the soln. struck per one pass is regulated to <=2g/m<2> on wet basis and wet-on-wet spreading is carried out through two or more passes. Thus, the thickness of a spread chromate soln. layer is made uniform and the layer can be smoothened.
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