Loading patent…
AssigneeArmco Steel Corporation
InventorsPaul E. Schnedler, Marvin B. Pierson, Hart F. Graff, Thomas A. Compton, William R. Leasure
Estimating the term…
Method and means for continuously contact-coating one side only of a ferrous base metal strip with a molten coating metal. One or more roll means are provided to conduct the strip surface to be coated above the surface of a bath of the molten coating metal. The strip surface to be coated is caused to travel sufficiently close to the molten coating metal bath surface that the surface tension and wetting characteristics of the coating metal will permit the formation of a meniscus which will continuously contact and coat the strip surface. The coating is subjected to jet finishing. The strip is maintained in a protective non-oxidizing atmosphere at least until the one side thereof is coated. The strip may be maintained in the protective non-oxidizing atmosphere until it is sufficiently cooled to prevent the formation of a visible oxide on the uncoated side thereof. When the strip is exposed to an oxidizing atmosphere after coating and while still sufficiently hot to form a visible oxide coating on the uncoated side thereof, the strip will thereafter be subjected to acid cleaning, rinsing and drying operations.
A process of producing a ferrous base metal strip coated with a coating metal on one side only, the other side of said strip remaining free of said coating metal, said ferrous base metal strip having been treated to bring it to a coating temperature sufficiently high to prevent casting of said coating metal thereon and low enough to prevent excess coating metal - base metal alloying and to render its surfaces clean and free of oxide, said process comprising the steps of providing means for containing a molten bath of said coating metal having an upper surface formed by said containing means, conducting said strip to a position above said upper surface of said bath such that the surface tension and wetting characteristics of said molten coating metal will permit the formation of a meniscus at said upper surface of said bath contacting that side of said strip facing said bath, forming said meniscus, maintaining said meniscus and continuously contact coating said one side only of said strip therewith, maintaining said oxide-free strip in a protective, non-oxidizing atmosphere at least until said one side of said strip has been initially contacted by said meniscus and finishing said coated side of said strip by removing excess coating metal therefrom.
In a process of hot dip metallic coating of a ferrous base metal strip to produce a coating on one-side only of said strip, the other side thereof remaining free of said coating metal, wherein said strip is preliminarily treated to render its surfaces clean and free of oxide, and is brought approximately to the temperature of a bath of said molten coating metal while surrounded by a protective atmosphere, conducted into contact with said coating metal bath, withdrawn from said bath with an excess of coating metal adhering to said strip, and finished by removal of excess molten coating metal, the improvement which comprises maintaining the upper surface of said bath as defined by a containing means for said bath at a constant level, conducting said strip to a position above said upper surface of said bath such that a meniscus of said molten coating metal is formed at said upper surface of said bath contacting that side of said strip facing said bath, maintaining said meniscus and continuously contact-coating said one-side only of said strip therewith, and maintaining said strip surrounded by said protective atmosphere at least until said one-side of said strip has been initially contacted by said meniscus.
Dependencies are inferred from the claim text.