Continuously Manufactured Colored Metallic Products and Method of Manufacture of Such Products
Metallic tube, pipe and conduit are made in a continuous process that includes a zinc galvanization stage, a first passivation stage, a second passivation stage and a third passivation stage. A colorant is added to the tube, pipe or conduit during the continuous manufacturing process, and the colorant imparts the appearance of a color, such as red. The continuous movement of the tube, pipe or conduit is not halted during normal operation of the tube, pipe or conduit manufacturing and coloring process.
1 . A method for imparting a colorant to a metallic surface during a continuous manufacturing process, comprising:
moving a metal tube in a continuous manufacturing process;
applying a coating to an inner surface of the metal tube;
galvanizing an outer surface of the metal tube;
applying a chromate coating over the galvanized surface, the chromate coating including a colorant; and
applying a clear organic polymer coating over the chromate coating.
2 . The method of claim 1 , wherein the colorant is a liquid colorant.
3 . The method of claim 1 , wherein the movement of a steel tube in the continuous manufacturing process has a rate of speed of more than about six hundred feet per minute.
4 . The method of claim 3 , wherein the movement of a steel tube in the continuous manufacturing process has a rate of speed of more than about one thousand feet per minute.
5 . The method of claim 1 , further comprising curing the colorant using ultraviolet light curing.
6 . The method of claim 1 , wherein the coating is a paint.
7 . The method of claim 1 , wherein the coating is a corrosion resistant coating.
8 . The method of claim 1 , wherein the coating is an antibacterial coating.
9 . A method for imparting a colorant to a metallic surface during a continuous manufacturing process, comprising:
moving a metal tube in a continuous manufacturing process;
applying a corrosion resistant coating to an inner surface of the metal tube;
galvanizing an outer surface of the metal tube;
applying a first passivation layer over the galvanized outer surface, the first passivation layer including chromium and a colorant; and
applying a clear organic polymer coating over the first passivation layer.
10 . The method of claim 9 , wherein the colorant is selected from the list consisting of pigment, powder, liquid, ink and identifying lacquer.
11 . The method of claim 9 , wherein the movement of a steel tube in the continuous manufacturing process has a rate of speed of more than about one thousand feet per minute.
12 . The method of claim 9 , further comprising curing the colorant using ultraviolet light curing.
13 . The method of claim 9 , wherein the continuous manufacturing process occurs at a substantially constant rate of speed.
14 . The method of claim 9 , wherein the colorant comprises a pigment, a powder, a liquid ink, or an identifying lacquer.
15 . A method for imparting a colorant to a metallic surface during a continuous manufacturing process, comprising:
moving a metallic tube in a continuous manufacturing process;
applying a coating to an inner surface of the metallic tube;
galvanizing an outer surface of the metallic tube;
applying first and second passivation layers over the galvanized outer surface; and
providing a colorant on or in the first passivation layer;
wherein the first passivation layer includes chromate, and the second passivation layer comprises a clear organic polymer coating.
16 . The method of claim 15 , wherein a third passivation layer is applied over the second passivation layer before the second and third passivation layers set or fully dry so that said second and third passivation layers intermingle to provide increased interconnectivity there between.
17 . The method of claim 16 , wherein at least one of the first, second and third passivation layers contains said colorant, and said passivation layer containing said colorant is applied as a pattern.
18 . The method of claim 15 , wherein the coating is an antibacterial coating.
19 . The method of claim 15 , wherein the coating is a corrosion resistant coating.
20 . The method of claim 15 , wherein the colorant comprises a pigment, a powder, a liquid ink, or an identifying lacquer.