EP0022566A1 - Procédé et dispositif pour le moulage électromagnétique de métaux liquides ou d'alliages, installation réfrigérante pour la coulée électromagnétique - Google Patents
Procédé et dispositif pour le moulage électromagnétique de métaux liquides ou d'alliages, installation réfrigérante pour la coulée électromagnétique Download PDFInfo
- Publication number
- EP0022566A1 EP0022566A1 EP80103976A EP80103976A EP0022566A1 EP 0022566 A1 EP0022566 A1 EP 0022566A1 EP 80103976 A EP80103976 A EP 80103976A EP 80103976 A EP80103976 A EP 80103976A EP 0022566 A1 EP0022566 A1 EP 0022566A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- casting
- coolant
- manifold
- elevation
- curvature
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 239000002826 coolant Substances 0.000 title claims abstract description 63
- 229910045601 alloy Inorganic materials 0.000 title claims abstract description 21
- 239000000956 alloy Substances 0.000 title claims abstract description 21
- 238000000034 method Methods 0.000 title claims abstract description 16
- 238000005266 casting Methods 0.000 title claims description 59
- 229910052751 metal Inorganic materials 0.000 title claims description 38
- 239000002184 metal Substances 0.000 title claims description 38
- 150000002739 metals Chemical class 0.000 title claims description 8
- 238000007711 solidification Methods 0.000 claims description 27
- 230000008023 solidification Effects 0.000 claims description 27
- 230000002093 peripheral effect Effects 0.000 claims description 26
- 230000003068 static effect Effects 0.000 claims description 14
- 238000013459 approach Methods 0.000 claims description 5
- 239000000463 material Substances 0.000 claims description 3
- 238000005058 metal casting Methods 0.000 abstract description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 29
- 238000001816 cooling Methods 0.000 description 11
- 239000000498 cooling water Substances 0.000 description 10
- 230000004048 modification Effects 0.000 description 7
- 238000012986 modification Methods 0.000 description 7
- 238000000605 extraction Methods 0.000 description 4
- 229910001338 liquidmetal Inorganic materials 0.000 description 4
- 238000005096 rolling process Methods 0.000 description 2
- 230000000903 blocking effect Effects 0.000 description 1
- 239000004020 conductor Substances 0.000 description 1
- 238000009749 continuous casting Methods 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
- 238000010908 decantation Methods 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 230000002706 hydrostatic effect Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000002344 surface layer Substances 0.000 description 1
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
- B22D11/01—Continuous casting of metals, i.e. casting in indefinite lengths without moulds, e.g. on molten surfaces
- B22D11/015—Continuous casting of metals, i.e. casting in indefinite lengths without moulds, e.g. on molten surfaces using magnetic field for conformation, i.e. the metal is not in contact with a mould
Definitions
- This invention relates to an improved process and apparatus for control of corner shape in continuous or semi-continuous electromagnetic casting of desired shapes, such as for example, sheet or rectangular ingots of metals and alloys.
- the basic electromagnetic casting process has been known and used for many years for continuously or semi-continuously casting metals and alloys.
- rounding off of corners in electromagnetic cashing can be made less severe or of smaller radius by contouring the coclant application rate or elevation (or both) so that the rate and/or elevation is a minimum at the corners of the ingot.
- Known electromagnetic casting apparatus comprises a three part mold consisting of a water cooled inductor, a non-magnetic screen and a manifold for applying cooling water to the ingot being cast.
- a three part mold consisting of a water cooled inductor, a non-magnetic screen and a manifold for applying cooling water to the ingot being cast.
- Such an apparatus is exemplified in U.S. Patent No. 3,467,166 to Getselev et al. Containment of the molten metal is achieved without direct contact between the molten metal and any component of the mold. Solidification of the molten metal is achieved by direct application of water from the cooling manifold to the forming ingot shell.
- the inductor is formed as part of the cooling manifold so that the cooling manifold supplies both coolant to solidify the casting and to cool the inductor. See U.S. Patent 4,004,631 to Goodrich et al.
- Non-magnetic screens of the prior art are typically utilized to properly shape the magnetic field for containing the molten metal as exemplified in U.S. Patent No. 3,605,865 to Getselev.
- Another approach with respect to use of non-magnetic screens is exemplified as well in U.S. Patent No. 3,985,179 to Goodrich'et al. Goodrich et al. '179 describes the use of a shaped inductor in conjunction with a screen to modify the electromagnetic forming field.
- a cooling medium is supplied upon the lateral face of the ingot in several cooling tiers arranged at various levels longitudinally of the ingot.
- the solidification front can be maintained within the inductor by appropriate selection of one of the tiers.
- the ingots are often cast with high radius of curvature ends or corners which is indicative of the need for improved ingot shape control at the corners of such ingots.
- United States Patent 3,502,133 to Carson teaches utilizing a sensor in a continuous or semi-continuous casting mold to sense temperature variations at a particular location in the mold during casting.
- the sensor controls application of coolant to the mold and forming ingot.
- Use of such a device overcomes instabilities with respect to how much extra coolant is required at start up of the casting operation and just when or at what rate this excess cooling should be reduced.
- the ultimate purpose of adjusting the flow of coolant is to maintain the freeze line of the casting at a substantially constant location.
- Carson '133 teaches that ingots having a width to thickness ratio on the order of 3 to 1 or more possess an uneven cooling rate during casting when coolant is applied peripherally of the mold in a uniform manner. To overcome this problem, Carson '133 applies coolant to the wide faces of the ingot and/or the mold walls and not at all (or at least at a reduced rate) to the relatively narrow end faces of the ingot and/or the mold walls.
- the present invention comprises a process and apparatus for electromagnetic casting of metals and alloys into rectangular or sheet ingots and other desired elements of shape control having small radius of curvature corners or portions by application of controlled static head (through metal head or pressure modification).
- controlled static head through metal head or pressure modification.
- a method and apparatus utilizing controlled differential static head by control of cooling water application to obtain refinement of ingot shape, particularly at the corners of rectangular ingots or other desired elements of shape in claimed.
- control of ingot shape may be effected by selection of the rate or location of cooling water application to the forming ingot shell within or below the containment inductor.
- Rounding off of corners in electromagnetic casting can be made less severe or of smaller radius by contouring the water application rate or elevation (or both) so that the rate or elevation is a minimum at the corners of'the ingot.
- Reduction of the water application rate or lowering the application level serves to reduce the local heat extraction rate along an ingot transverse cross section line of constant height. This in turn lowers the position of the solidification front at the ingot corner and correspondingly raises the metal static head or pressure at the corner.
- This increased pressure results in the liquid metal approaching the inductor more closely at the corner and thus filling the corner to form a smaller radius of curvature at the corner before the increased static pressure is counterbalanced by an increased electromagnetic force.
- a water manifold or cooling water application device is provided with drilled holes or slots of a size and/or local hole density which is modified to yield locally reduced rates of water application at the ingot or desired shape corners.
- a water manifold or cooling water application device wherein the elevation of the supply holes is modified so as to apply water at the lowest elevation at the ingot or desired shape corners.
- the holes or slots in a water manifold or cooling water application device are modified such that the angle of the holes or slots around the corners of the ingot cause the water to impinge cn the ingot surface at a lower elevation at the ingot corners.
- a water manifold or cooling water application device which produces a water application rate of zero over short distances at the corners of the ingot or desired shape to further accentuate the effects of reduced local cooling.
- FIGURE 1 there is shown therein a prior art electromagnetic casting apparatus in accordance with U.S. Patent 4,158,379.
- the electromagnetic casting mold 10 is comprised of an inductor 11 which is water cooled; a coolant manifold 12 for applying cooling water to the peripheral surface 13 of the metal being cast C; and a non-magnetic screen 14. Molten metal is continuously introduced into the mold 10 during a casting run, in the normal manner using a trough 15 and down spout 15 and conventional molten metal head control.
- the inductor 11 is excited by an alternating current from a suitable power source (not shown).
- the alternating current in the inductor 11 produces a magnetic field which interacts with the molten metal head 19 to produce eddy currents therein. These eddy currents in turn interact with the magnetic field and produce forces which apply a magnetic pressure to the molten metal head 1 9 to contain it so that it solidifies in a desired ingot cross section.
- the molten metal head 19 is formed or molded into the same general shape as the inductor 11 thereby providing the desired ingot cross section.
- the inductor may have any desired shape including circular or rectangular as required to obtain the desired ingot C cross section.
- the purpose of the non-magnetic screen 14 is to fine tune and balance the magnetic pressure with the hydrostatic pressure of the molten metal head 19.
- the non-magnetic screen 14 comprises a separate element as shown, and is not a part of the manifold 12 for applying the coolant.
- a conventional ram 21 and bottom block 22 is held in the magnetic containment zone of the mold 10 to allow the molten metal to be poured into the mold at the start of the casting run.
- the ram 21 and bottom block 22 are then uniformly withdrawn at a desired casting rate.
- Solidification of the molten metal which is magnetically contained in the mold 10 is achieved by direct application of water from the cooling manifold 12 to the ingot surface 13.
- the water is shown applied to the ingot surface 13 within the confines of the inductor 11.
- the water may be applied, however,to the ingot surface 13 from above, within or below the inductor 11 as desired.
- the solidification front 25 of the casting comprises the boundary between the molten metal head 19 and the solidified ingot C.
- the location of the solidification front 25 at the ingot surface 13 results from a balance of the heat input from the superheated liquid metal 19 and the resistance heating from the induced currents in the ingot surface layer, with the longitudinal heat extraction from the cooling water application.
- Coolant manifold 12 is arranged above the inductor 11 and includes at least one discharge port 28 at the end of extended portion 30 for directing the coolant against the surface 13 of the ingot or casting.
- the discharge port 28 can comprise a slot or a plurality of individual orifices for directing the coolant against the surface 13 of the ingot C about the entire periphery of that surface.
- Coolant manifold 12 is arranged for movement along vertically extending rails 38 and 39 axially of the ingot c such that extended portion 30 and discharge port 28 can be moved between the non-magnetic screen 14 and the inductor 11. Axial adjustment of the discharge port 28 position is provided by means of cranks 40 mounted to screws 41.
- the coolant is discharged against the surface of the casting in the direction indicated by arrows 43 to define the place of coolant application.
- Figure 2 is a schematic cross-sectional representation of one embodiment of a system for application of a coolant in accordance with this invention.
- Line 29 divides Figure 2 into two sides (A) and (B).
- Side (A) shows a section through a face of rectangular ingot 20 and inductor 11' while side (B) shows a section through the corner of the same elements.
- Coolant typically water, is supplied to the peripheral surface 13 of ingot 20 via holes 17 in inductor
- dotted line 23 exemplifies the location of the solidfication front at the corner of an ingot (side (B)) which is cooled by known uniform rate and height peripheral coolant flow directed to the surface 13 of rectangular ingot 20.
- excess cooling at the corners of the ingot 20 cause the solidification front to rise in comparison to the elevation of the solidification front along the faces of the ingot 20 (side (A)), denoted by dashed line 24.
- the height" of the solidification front from the point of coolant impingement at the corners of the ingot 20 is greater than a, the height of the solidification front from the point of coolant impingement along the faces of the ingot 20.
- coolant application devices are modified to produce controlled differential static head leading to refinement of ingot shapes at the corners, and in particular to form smaller radius of curvatures at ingot corners.
- Control of ingot shape is effected in accordance with the present invention by selection of the rate and/or location of cooling water impingement upon the surface of forming ingot shells.
- Rounding off of corners in electromagnetic casting can be made less severe or of smaller radius by contouring the water application rate and/or elevation so that the rate and/or elevation is a minimum at the corner of the ingot.
- Reduction of the water application rate and/or lowering of the application level serves to reduce the local heat extraction rate along an ingot transverse cross section line of constant height. This in turn lowers the position of the solidification front at the ingot corners and correspondingly raises the metal static head or pressure at the corners.
- This increased pressure results in the liquid metal approaching the inductor more closely at the corners and thereby filling the corner to form a smaller radius of curvature before the increased static pressure is counterbalanced by the increased electromagnetic force.
- the elevation of the water impingement at the side (B) (the corner of ingot 20) in accordance with this invention is lower than the elevation at side (A) (along the face of the ingot 20) by virtue of the modification in elevation and angle of holes 17 in inductor 11'.
- the solidification front 25 forms as a result at a height b above the point of water impingement (point 26) but at a level lower than the point 27 where the solidification front 25 forms along the faces of ingot 20.
- Figure 3 shows a partial schematic cross-sectional representation of the electromagnetic casting apparatus of Figure 1 with a modified coolant manifold 12' in accordance with another embodiment of this invention.
- Figure 3 shows extended portion 30 to have a discharge port 28' (Side (B)) having a modified slot discharge angle causing impingement of coolant water at a lower elevation at the corners of ingot 20.
- Side (A) shows a standard or unmodified discharge port 28 which impinges water at a higher level along the faces of ingot 20.
- Solidification front 25 is seen to be at a higher level as designated by point 27 along the faces of the ingot than at or near the corners of ingot 20, designated by point 26.
- Figure 4 shows a partial schematic cross-sectional representation of the electromagnetic casting apparatus of Figures 1 and 3 with a modified coolant manifold 12" in accordance with yet another embodiment of this invention.
- extended portion 30 of modified coolant manifold 12 n is constructed with discharge port 28 completely blocked off at or near the corners of ingot 20 (Side (B)) by portion 31 of coolant manifold 12".
- discharge port 28 completely blocked off at or near the corners of ingot 20 (Side (B)) by portion 31 of coolant manifold 12".
- slot cross section can be accurately contoured to produce a smoothly varying water flow rate with a minimum or zero flow rate at or near the ingot corner positions.
- Figure 5 is a bottom plan view looking up into an extended portion 30 of a manifold and shows corners possessing different slot modifications in accordance with this invention.
- Extended portion 30 comprises an inner wall 32, an cuter wall 34 and a discharge port 28.
- Corner c shows an unmodified full slot discharge port 28 with a slot width equal to that along the four faces of extended portion 30.
- Corner D shows a contoured slot discharge port 28 with zero slot width (closed) at the exact corner 62 of extended portion 30.
- Corner E shows a contoured slot discharge port 28 with zero slot width over about half the corner radius 64 of extended portion 30 and corner F shows zero slot width over about virtually the whole corner radius 66 of extended portion 3C.
- the aforedescribed variants in coolant applying equipment are typically designed so as to modify the coolant application rate and/or impact point within about three inches on either side of a corner while the maximum extent of the modifications in coolant application is to result in substantial absence of coolant application over about one inch or less of the ingot surface about the corner.
- novel method and apparatus of the present invention find applicability in the electromagnetic casting of any shapes wherein it is desired to form portions thereon of low radius of curvature.
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Continuous Casting (AREA)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US5677379A | 1979-07-11 | 1979-07-11 | |
US56773 | 1979-07-11 |
Publications (2)
Publication Number | Publication Date |
---|---|
EP0022566A1 true EP0022566A1 (fr) | 1981-01-21 |
EP0022566B1 EP0022566B1 (fr) | 1986-01-08 |
Family
ID=22006506
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP80103976A Expired EP0022566B1 (fr) | 1979-07-11 | 1980-07-10 | Procédé et dispositif pour le moulage électromagnétique de métaux liquides ou d'alliages, installation réfrigérante pour la coulée électromagnétique |
Country Status (4)
Country | Link |
---|---|
EP (1) | EP0022566B1 (fr) |
JP (1) | JPS5614056A (fr) |
CA (1) | CA1161107A (fr) |
DE (1) | DE3071333D1 (fr) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN107243609A (zh) * | 2017-06-16 | 2017-10-13 | 浙江天宁合金材料有限公司 | 一种铜及铜合金浇铸结晶器 |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CA1192372A (fr) * | 1981-06-26 | 1985-08-27 | Michael J. Pryor | Systeme de controle a priorites pour la coulee electromagnetique |
Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3467166A (en) * | 1967-03-01 | 1969-09-16 | Getselev Zinovy N | Method of continuous and semicontinuous casting of metals and a plant for same |
US3646988A (en) * | 1970-05-20 | 1972-03-07 | Getselev Zinovy N | Induction apparatus for continuous and semicontinuous casting |
AU460318B2 (en) * | 1971-11-10 | 1975-04-24 | Kuibyshevsky Metallurgichesky Zavod Imerti Vi. Lenina | Ingot-producing plant |
US4014379A (en) * | 1970-06-09 | 1977-03-29 | Getselev Zinovy N | Method of forming ingot in process of continuous and semi-continuous casting of metals |
US4158379A (en) * | 1978-07-03 | 1979-06-19 | Olin Corporation | Electromagnetic casting method and apparatus |
FR2429633A1 (fr) * | 1979-03-08 | 1980-01-25 | Gi Splavov | Procede de coulee continue d'un metal dans un champ electromagnetique et installation pour la mise en oeuvre dudit procede |
Family Cites Families (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3985179A (en) * | 1975-07-28 | 1976-10-21 | Kaiser Aluminum & Chemical Corporation | Electromagnetic casting apparatus |
US4156451A (en) * | 1978-02-07 | 1979-05-29 | Getselev Zinovy N | Continuous or semi-continuous metal casting method |
-
1980
- 1980-05-16 CA CA000352198A patent/CA1161107A/fr not_active Expired
- 1980-06-04 JP JP7538980A patent/JPS5614056A/ja active Pending
- 1980-07-10 DE DE8080103976T patent/DE3071333D1/de not_active Expired
- 1980-07-10 EP EP80103976A patent/EP0022566B1/fr not_active Expired
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3467166A (en) * | 1967-03-01 | 1969-09-16 | Getselev Zinovy N | Method of continuous and semicontinuous casting of metals and a plant for same |
US3646988A (en) * | 1970-05-20 | 1972-03-07 | Getselev Zinovy N | Induction apparatus for continuous and semicontinuous casting |
US4014379A (en) * | 1970-06-09 | 1977-03-29 | Getselev Zinovy N | Method of forming ingot in process of continuous and semi-continuous casting of metals |
AU460318B2 (en) * | 1971-11-10 | 1975-04-24 | Kuibyshevsky Metallurgichesky Zavod Imerti Vi. Lenina | Ingot-producing plant |
US4158379A (en) * | 1978-07-03 | 1979-06-19 | Olin Corporation | Electromagnetic casting method and apparatus |
FR2429633A1 (fr) * | 1979-03-08 | 1980-01-25 | Gi Splavov | Procede de coulee continue d'un metal dans un champ electromagnetique et installation pour la mise en oeuvre dudit procede |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN107243609A (zh) * | 2017-06-16 | 2017-10-13 | 浙江天宁合金材料有限公司 | 一种铜及铜合金浇铸结晶器 |
Also Published As
Publication number | Publication date |
---|---|
CA1161107A (fr) | 1984-01-24 |
JPS5614056A (en) | 1981-02-10 |
DE3071333D1 (en) | 1986-02-20 |
EP0022566B1 (fr) | 1986-01-08 |
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