Gas injection pump

• US 5,993,728 A
• Filed: 07/25/1997
• Issued: 11/30/1999
• Est. Priority Date: 07/26/1996
• Status: Expired due to Term

• Current Assignee: Pyrotek Incorporated
• Original Assignee: Metaullics Systems Company LP (Pyrotek Incorporated)
• Inventors: Vild, Chris T.
• Primary Examiner(s): ANDREWS, MELVYN J
• Application Number:
  US08/900,433
• Time in Patent Office: 858 Days
• Field of Search: 266/217, 266/235, 75/680, 75/681
• US Class Current: 266/217
• CPC Class Codes: C22B 21/064 using inert or reactive gases C22B21/066 and C22B21/068 take precedence
• CPC Class Codes: C22B 9/05 Refining by treating with gases, e.g. gas flushing also refining by means of a material generating gas in situ
• CPC Class Codes: F04D 7/065 for liquid metal

Abstract

An apparatus for treating molten aluminum or zinc having a housing providing a chamber for containing a molten metal. The chamber including an inlet opening and an outlet passage. A rotatable impeller disposed within the chamber for drawing molten metal in through the inlet and expelling molten metal through the outlet passage. A convergent nozzle being positioned in the outlet passage. A gas injection conduit having an inlet in fluid communication with a source of purifying gas and an outlet in proximity to the chamber, and positioned upstream of the nozzle.

Claims

1. An apparatus for treating molten aluminum or zinc comprising:

a) a housing providing a chamber for containing a molten metal, said chamber including an inlet opening and an outlet passage;

b) a rotatable impeller disposed within said chamber for drawing molten metal in through said inlet opening and expelling molten metal through said outlet passage and creating a flow of molten metal generally from said inlet opening to said outlet passage, said outlet passage including a nozzle having a convergent inlet and a divergent outlet wherein said angle of said divergent outlet is greater than the angle of said convergent inlet; and

c) a gas injection conduit having an inlet in fluid communication with a source of purifying gas and an exit in proximity to said chamber, said gas injection conduit exit being positioned upstream of said nozzle.

2. The apparatus of claim 1 wherein said gas injection conduit is comprised of a material chemically resistant to chlorine gas.

3. The apparatus of claim 1 wherein said conduit exit is positioned within said chamber.

4. The apparatus of claim 1 wherein said conduit exit is positioned within said chamber outlet passage.

5. The apparatus of claim 1 wherein said conduit exit is positioned within said nozzle.

6. The apparatus of claim 1 being comprised substantially of graphite or ceramic.

7. The apparatus of claim 1 wherein said outlet passage includes a convergent-divergent nozzle upstream of a final opening of said outlet passage into a molten metal bath.

8. The apparatus of claim 1 wherein said outlet passage includes said nozzle adjacent a final opening of said outlet passage into a molten metal bath.

9. The apparatus of claim 1 wherein said nozzle is formed as an integral element of said outlet passage.

10. The apparatus of claim 1 wherein said nozzle is formed as an insert secured within said outlet passage.

11. The apparatus of claim 1 wherein said outlet passage is formed by a separate element secured to said housing.

12. The apparatus of claim 2 wherein said gas injection conduit is secured to said housing via a connector member.

13. The apparatus of claim 7 wherein the gas injection conduit exit is in a divergent zone downstream of said nozzle within said outlet passage.

14. An apparatus for treating molten aluminum or zinc comprising:

a) a housing providing a chamber for containing a molten metal, such chamber including an inlet opening and outlet passage;

b) a rotatable impeller disposed within said chamber for drawing molten through said inlet and expelling molten metal through said outlet passage, said outlet passage including a convergent nozzle, said convergent nozzle including a terminal downstream portion which allows for substantially immediate expansion of said molten metal to the walls of the outlet passage or the exterior of said outlet passage and;

c) a gas injection conduit having an inlet in fluid communication with a source of purifying gas and an outlet in proximity to said chamber, said gas injection conduit being positioned upstream of said nozzle.