Process for melting metal

• US 3,935,003 A
• Filed: 02/25/1974
• Issued: 01/27/1976
• Est. Priority Date: 02/25/1974
• Status: Expired due to Term

• Current Assignee: Kaiser Aluminum & Chemical Corporation (Kaiser Aluminum Corporation)
• Original Assignee: Kaiser Aluminum & Chemical Corporation (Kaiser Aluminum Corporation)
• Inventors: Carter, Melvin A., Steinke, Theodore D.
• Primary Examiner(s): Andrews, M. J.
• Application Number:
  US05/445,721
• Time in Patent Office: 701 Days
• Field of Search: 75/68, 75/65, 75/93, 75/46, 75/68 R, 75/65 R, 266/33 R, 266/33 S
• US Class Current: 75/686
• CPC Class Codes: C22B 21/0084 melting and handling molten aluminium C22B21/02, C22B21/04 and C22B21/06 take precedence
• CPC Class Codes: C22B 9/00 General processes of refining or remelting of metals; Apparatus for electroslag or arc remelting of metals
• CPC Class Codes: F27B 19/04 arranged for associated working

Abstract

This invention relates to an improved method of melting metal, particularly reactive metals, such as aluminum, wherein heated molten metal is withdrawn from a first chamber and a portion of the withdrawn molten metal is transferred to a second chamber containing solid metal so as to melt same and a portion of the withdrawn metal is recirculated to the first chamber so as to maintain melt homogenuity therein.

Claims

1. A method of melting metal comprising

a. maintaining a body of molten metal in a heating chamber;

b. withdrawing molten metal from said heating chamber;

c. pumping a portion of said withdrawn molten metal to a melting chamber containing solid metal so as to melt said solid metal;

d. pumping a portion of said withdrawn molten metal to said heating chamber so as to maintain a substantially homogeneous melt in said heating chamber; and

e. returning molten metal from said melting chamber to said heating chamber.

2. The method of claim 1 wherein said metal is aluminum.

3. The method of claim 1 wherein the temperature differential between the molten metal withdrawn from said heating chamber and the molten metal returned from said melting chamber to said heating chamber is at least 10°

F.

4. The method of claim 3 wherein the temperature differential is between about 50°

and about 100°

F.

5. The method of claim 1 wherein the amount of molten metal pumped to said melting chamber per minute is at least 2% of the total metal, both solid and liquid, in the heating and melting chambers.

6. The method of claim 1 wherein the amount of molten metal transferred to said melting chamber per minute is at least 10% of the total metal, both solid and liquid, in the heating and melting chambers.

7. The method of claim 1 wherein the amount of molten metal recirculated to said heating chamber is about 5-50% of the total molten metal withdrawn from said heating chamber.

8. The method of claim 1 wherein the amount of molten metal recirculated to said heating chamber is about 5-30% of the total molten metal withdrawn from said heating chamber.

9. The method of claim 1 wherein the oxide on the surface of the molten metal in said heating chamber is controlled to a thickness of less than 1/2 inch.

10. The method of claim 1 wherein the oxide on the surface of the molten metal in said heating chamber is controlled to less than 1/10 th inch.