Claims
- 1. An apparatus for melting aluminum or aluminum alloys comprising:
- a shaft furnace having a cylindrical melting chamber, said chamber having a vertical axis, said furnace having a concave hearth with a taphole for withdrawing the molten aluminum or aluminum alloy metal, said hearth having a generally conical shape and a hearth center substantially aligned with the vertical axis of the chamber, said furnace having an outlet trough extending in a downwardly sloping direction from the hearth center to the taphole for flowing the molten metal directly from the hearth to the taphole without forming a bath or pool of molten metal;
- charging means for charging said shaft furnace with aluminum or an aluminum alloy metal charge; and
- means for transferring sufficient heat to said aluminum or aluminum alloy metal substantially completely by convection to completely melt said metal in a lower portion of said shaft furnace, said heat transferring means including means for directing heat from at least four burners into an aluminum or aluminum alloy metal charge at the lower portion of said furnace, said burners each having an axis the axes of said burners being disposed such that vertical planes passing through each axis of said at least four burners are non-coincident vertical planes and said axes are downwardly inclined such that the heat of said burners is directed to impinge upon regions on the concave hearth disposed opposite the respective burners whereby blowing of molten, semi-molten or solid metal into said burners is prevented, said vertical planes passing through the axes of the at least four bunrers intersecting one another adjacent the vertical axis of the chamber but offset from said vertical axis in a direction toward the taphole to form a heating zone thereat.
- 2. The apparatus according to claim 1, wherein the inclination of said burners is 15.degree. to 45.degree. downward.
- 3. The apparatus according to claim 2, wherein the inclination of said burners is about 30.degree. downward.
- 4. The apparatus according to claim 1, wherein said concave hearth and outlet trough up to the taphole are integrally formed in one piece.
- 5. The apparatus according to claim 1, wherein the outlet trough has a centerline, the vertical planes passing through a first pair of said burner axes forming first and second equal angles with said centerline on opposite sides thereof, the vertical planes passing through the second pair of burner axes forming third and fourth equal angles with said centerline on opposite sides thereof, said first and second angles being different from said third and fourth angles.
- 6. The apparatus according to claim 5, wherein said first and second angles are about 60.degree. and said third and fourth angles are about 35.degree., said first and second angles being oriented toward said taphole and said third and fourth angels being oriented away from said taphole.
- 7. The apparatus according to claim 1 wherein the outlet trough is downwardly sloped about 15.degree. from the center of the hearth and has in cross-section a generally V-shaped groove with a flat bottom.
- 8. The apparatus according to claim 1, wherein the outlet trough has a centerline and including a fifth burner having an axis aligned with a vertical plane through the centerline of the outlet trough, said fifth burner being downwardly inclined toward the outlet trough in a direction opposite the flow of molten metal in said trough.
Parent Case Info
This is a divisional of co-pending application Ser. No. 697,605, filed on 2/4/85, now U.S. Pat. No. 4,664,702.
US Referenced Citations (1)
Number |
Name |
Date |
Kind |
3663203 |
Davis et al. |
May 1972 |
|
Foreign Referenced Citations (1)
Number |
Date |
Country |
1360793 |
Jul 1974 |
GBX |
Divisions (1)
|
Number |
Date |
Country |
Parent |
697605 |
Feb 1985 |
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