Transferring molten metal using non-gravity assist launder

• US 10,072,891 B2
• Filed: 04/17/2015
• Issued: 09/11/2018
• Est. Priority Date: 06/21/2007
• Status: Active Grant

• Current Assignee: Molten Metal Equipment Innovations Incorporated (Molten)
• Original Assignee: Molten Metal Equipment Innovations Incorporated (Molten)
• Inventors: Cooper, Paul V.
• Primary Examiner(s): Kastler, Scott R
• Application Number:
  US14/689,879
• Publication Number:
  US 20150224574A1
• Time in Patent Office: 1,243 Days
• Field of Search: 266235
• CPC Class Codes: B22D 37/00 Controlling or regulating the pouring of molten metal from a casting melt-holding vessel B22D11/18, B22D39/00, B22D41/00 take precedence
• CPC Class Codes: B22D 39/00 Equipment for supplying molten metal in rations
• CPC Class Codes: B22D 41/00 Casting melt-holding vessels, e.g. ladles, tundishes, cups or the like B22D39/00, B22D43/00 take precedence
• CPC Class Codes: B22D 7/00 Casting ingots, e.g. from ferrous metalsequipment for conveying molten metal B22D35/00
• CPC Class Codes: C22B 21/0084 melting and handling molten aluminium C22B21/02, C22B21/04 and C22B21/06 take precedence
• CPC Class Codes: C22B 21/064 using inert or reactive gases C22B21/066 and C22B21/068 take precedence
• CPC Class Codes: F27D 27/005 Pumps
• CPC Class Codes: F27D 3/0024 of metallic workpieces
• CPC Class Codes: F27D 3/14 Charging or discharging liquid or molten material

Abstract

A system and method for transferring molten metal from a vessel and into a launder is disclosed. The system includes at least a vessel for containing molten metal, an overflow (or dividing) wall, and a device or structure, such as a molten metal pump, for generating a stream of molten metal. The dividing wall divides the vessel into a first chamber and a second chamber, wherein part of the second chamber has a height H2. The device for generating a stream of molten metal, which is preferably a molten metal pump, is preferably positioned in the first chamber. When the device operates, it generates a stream of molten metal from the first chamber and into the second chamber. When the level of molten metal in the second chamber exceeds H2, molten metal flows out of the vessel and into the launder. The launder has a horizontal angle of between 0° and −10° to help prevent dross from being pulled by gravity into downstream vessels.

Claims

1. A method for pumping molten metal out of a first vessel, the first vessel comprising at least a bottom surface, a first chamber and a second chamber that each have the bottom surface, the second chamber having a back wall with an outlet at a height H2, the first chamber and second chamber being separated by a dividing wall, the dividing wall having an opening above the bottom surface and wherein the opening does not extend to the bottom surface, and a pump positioned in the first chamber and including a pump base fully submerged in the molten metal in the first chamber, the pump base having a discharge, the discharge aligned with the opening in the dividing wall, the method comprising the steps of:

positioning the pump into the first chamber so the pump base is fully submerged in the molten metal and the discharge is aligned with the opening in the dividing wall; and

operating the pump to pump molten metal from the first chamber through the pump discharge and through the opening in the dividing wall and into the second chamber, until the level of molten metal in the second chamber reaches a level at which it flows out of the second chamber and out of the first vessel.

2. The method of claim 1 that further includes a launder extending from the back wall in the second chamber and that further includes the step of pumping the molten metal with enough pressure to cause it to move through the launder.

3. The method of claim 2 wherein the launder has a horizontal, backward angle between 0°

and 5°

.

4. The method of claim 2 wherein the launder has a horizontal, backward angle between 0°

and 3°

.

5. The method of claim 2 wherein the launder has a horizontal, backward angle between 1°

and 3°

.

6. The method of claim 1 wherein the pumping is not continuous.

7. The method of claim 2 wherein the opening is positioned below the launder.

8. The method of claim 1 wherein a circulation pump positioned in the first chamber performs the pumping.

9. The method of claim 1 wherein a gas-release pump positioned in the first chamber performs the pumping.

10. The method of claim 2 further comprising the step of measuring an amount of molten metal within one or both of the launder and the second chamber.

11. The method of claim 10 further comprising the step of adjusting the speed of the pumping in response to the measured amount.

12. The method of claim 1 wherein the pumping is performed at a variable speed.

13. The method of claim 1 wherein the pumping is performed at a constant speed.

14. The method of claim 2 wherein the launder splits into multiple branches.

15. The method of claim 1 that further includes the step of positioning the dividing wall in the first vessel.

16. The method of claim 1 that further includes the steps of (a) measuring a distance from a top edge of the dividing wall to the opening, and (b) building the pump having a height based at least in part on the distance.

17. The method of claim 8 that further includes the steps of (a) measuring a distance from a top edge of the dividing wall to the opening, and (b) building the circulation pump having a height based at least in part on the distance.