MIXING EDUCTOR NOZZLE AND FLOW CONTROL DEVICE
Techniques are disclosed for reducing macrosegregation in cast metals. Techniques include providing an eductor nozzle capable of increasing mixing in the fluid region of an ingot being cast. Techniques also include providing a non-contacting flow control device to mix and/or apply pressure to the molten metal that is being introduced to the mold cavity. The non-contacting flow control device can be permanent magnet or electromagnet based. Techniques additionally can include actively cooling and mixing the molten metal before introducing the molten metal to the mold cavity.
1 . A system comprising:
a feed tube couplable to a source of molten metal;
a primary nozzle located at a distal end of the feed tube, wherein the primary nozzle is submersible in a molten sump for delivering the molten metal to the molten sump;
a secondary nozzle submersible in the molten sump and positionable adjacent the primary nozzle, wherein the secondary nozzle includes a restriction shaped to generate a low pressure area to circulate the molten sump in response to the molten metal from the source passing through the restriction
a second primary nozzle located at the distal end of the feed tube, wherein the second primary nozzle is submersible in the molten sump for delivering the molten metal to the molten sump;
a second secondary nozzle submersible in the molten sump and positionable adjacent the second primary nozzle, wherein the second secondary nozzle includes a second restriction shaped to generate a second low pressure area to circulate the molten sump in response to the molten metal from the source passing through the second restriction; and
a flow control device adjacent the feed tube for controlling flow of the molten metal through the primary nozzle and the second primary nozzle, wherein the flow control device includes a plurality of permanent magnets positioned around the feed tube for generating a magnetic field through the feed tube and a plurality of electrodes electrically coupled to a pathway within the feed tube for conducting an electrical current through the molten metal within the feed tube.
2 . The system of claim 1 , wherein the molten sump is liquid metal of an ingot being cast.
3 . The system of claim 1 , wherein the molten sump is liquid metal within a furnace.
4 . The system of claim 1 , wherein the secondary nozzle is coupled to the primary nozzle.
5 . The system of claim 1 , further comprising a temperature control device positioned adjacent the feed tube for removing heat from the molten metal within the feed tube.
6 . The system of claim 5 , further comprising:
a temperature probe adjacent the feed tube for measuring a temperature of the molten metal; and
a controller coupled to the temperature probe and the temperature control device to adjust the temperature control device in response to the temperature measured by the temperature probe.
7 . The system of claim 1 , wherein the primary nozzle is rectangular in shape.
8 . A system, comprising:
a feed tube couplable to a source of molten metal;
a nozzle located at a distal end of the feed tube, wherein the nozzle is submersible in a molten sump for delivering the molten metal to the molten sump;
a flow control device positioned adjacent the feed tube, wherein the flow control device includes at least one magnetic source for inducing movement of the molten metal within the feed tube; and
a power source, wherein the feed tube includes a plurality of electrodes coupled to the power source for providing a current through the molten metal in the feed tube.
9 . The system of claim 8 , wherein the movement of the molten metal is a rotational movement within the feed tube, and wherein the feed tube includes an inner wall shaped at an angle to generate longitudinal movement of the molten metal in the feed tube in response to the rotational movement of the molten metal in the feed tube.
10 . The system of claim 8 , further comprising a temperature control device positioned adjacent the feed tube for removing heat from the molten metal within the feed tube.
11 . The system of claim 10 , further comprising:
a temperature probe adjacent the feed tube for measuring a temperature of the molten metal; and
a controller coupled to the temperature probe and the temperature control device to adjust the temperature control device in response to the temperature measured by the temperature probe.
12 . The system of claim 10 , further comprising a secondary nozzle submersible in the molten sump and positionable adjacent the nozzle, wherein the secondary nozzle includes a restriction shaped to generate a low pressure area to circulate the molten sump in response to the molten metal from the source passing through the restriction.
13 . An apparatus, comprising:
a feed tube including a plate nozzle having a first plate and a second plate coupled together in parallel, wherein the feed tube defines a passageway for directing molten metal through the plate nozzle toward at least one exit nozzle; and
a flow control device coupled to the feed tube for controlling the flow of molten metal through the plate nozzle, wherein the flow control device includes at least one static permanent magnet positioned adjacent the feed tube to generate a magnetic field through the passageway and a pair of electrodes positioned in the feed tube in contact with the passageway.
14 . The apparatus of claim 13 , further comprising a secondary nozzle submersible in a molten sump and positionable adjacent the at least one exit nozzle of the plate nozzle, wherein the secondary nozzle includes a restriction shaped to generate a low pressure area to circulate the molten sump in response to molten metal from the plate nozzle passing through the restriction.
15 . The apparatus of claim 13 , wherein the secondary nozzle is removably couplable to the plate nozzle.
16 . The apparatus of claim 13 , wherein the at least one exit nozzle includes two exit nozzles for directing the molten metal in non-parallel directions.
17 . The apparatus of claim 16 , further comprising two secondary nozzles submersible in a molten sump, wherein each secondary nozzle is positionable adjacent a respective one of the two exit nozzles of the plate nozzle, wherein each of the two secondary nozzles includes a restriction shaped to generate a low pressure area to circulate the molten sump in response to molten metal from the respective ones of the two exit nozzles passing through the restriction.
18 . The apparatus of claim 16 , wherein the pair of electrodes and the at least one static permanent magnet are positioned such that the direction of the magnetic field and the direction of an electrical current passing through the pair of electrodes within the passageway are both oriented perpendicular to a length of the feed tube.