GB451771A - Improvements in or relating to coated sheet metal and process of making the same - Google Patents

Abstract

451,771. Making compound sheets. WEAN ENGINEERING CO., Inc., Warren, Ohio, U.S.A.-(Assignees of Wean, R. J.) Feb. 11, 1935, No. 4333. Convention date, Feb. 20, 1934. [Class 83 (ii)] [See also Groups II, X, XVII, and XXIII] Coated sheet metal is manufactured by subjecting a metallic base to centrifugal blasting, with or without a preceding pickling treatment, prior to the application of the metal coating. The coating may be carried out by dipping and the base metal may be in the form of strip, preferably of long length. The opposite surfaces of the strip may be centrifugally abraded to different extents or the strip may be pickled, dried, and one side only then subjected to the centrifugal blast. A strip formed by hot rolling or hot and cold rolling from a slab of metal is fed from a reel 6, Fig. 2, over table 7a, 7b, to a reel 8 and in its passage over the table is subjected to the action of abrasive particles 9, e.g. sand or metal shot, from centrifugal blasting wheels 10 and 11. Each wheel comprises spiral passages 15 by which the material is ejected and to which it is fed through a pipe 13 leading into a stationery member 14 having an opening extending around a limited portion only of its periphery. The cleaned and roughened strip is fed through a bath 16 of acidulated water, Fig. 4, and then through a layer of flux 20 into molten metal, e.g. tin lead, or zinc, in a pot 17 heated by burners 18. A thin coating of tin may be applied prior to coating with a thicker coating of lead. The final appearance of the coated metal may be varied by varying the force of the blasting and the thickness of the coating. The coated product may, for example, be used for roofing, culverts, and fencing, for which purposes strips of long length are preferably employed, for billboards, and for baking pans having a " silver-tin " finish. U.S.A. Specification 1,953,566 is referred to.