US3565158A - Continuous-casting mold - Google Patents
Continuous-casting mold Download PDFInfo
- Publication number
- US3565158A US3565158A US772900A US3565158DA US3565158A US 3565158 A US3565158 A US 3565158A US 772900 A US772900 A US 772900A US 3565158D A US3565158D A US 3565158DA US 3565158 A US3565158 A US 3565158A
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- Prior art keywords
- envelope
- annular space
- tubular
- mold
- envelopes
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- 238000009749 continuous casting Methods 0.000 title abstract description 13
- 239000012530 fluid Substances 0.000 claims description 9
- 239000002184 metal Substances 0.000 claims description 9
- 239000012809 cooling fluid Substances 0.000 claims description 5
- 238000005266 casting Methods 0.000 description 5
- 229910000831 Steel Inorganic materials 0.000 description 3
- 239000000498 cooling water Substances 0.000 description 3
- 239000010959 steel Substances 0.000 description 3
- 238000009835 boiling Methods 0.000 description 2
- 238000001816 cooling Methods 0.000 description 1
- 238000002425 crystallisation Methods 0.000 description 1
- 230000008025 crystallization Effects 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
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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
- B22D11/04—Continuous casting of metals, i.e. casting in indefinite lengths into open-ended moulds
- B22D11/053—Means for oscillating the moulds
Definitions
- the present invention discloses a novel and improved mold, which is equipped'with vibratory apparatus that produces a continuous-cast strand having greatly improved metallurgical structure.
- Cooling water flows into the lower annular space 23b and into the annulus 29. Thence, the cooling water courses upward to the top of theannulus 29, and into the upper annular space 230. Fluid discharge openings 35 are provided at the bottom of the upper annular space 23a to discharge the cooling water.
- the cylindrical outer envelope 13 supports four resiliently mounted vibrators 37 that are disposed at the ends of diameters that are both mutually perpendicular and perpendicular to the four walls of the mold 15.
- the vibrators 37 may be of any suitable type having a range of frequencies between 700 and l,500 c.p.s. and an amplitude of between two-thousandths and eight-thousandths of an inch.
- Each vibrator 37 is mounted to a vertical, rectangular plate 39 spaced apart from and disposed perpendicularly to the diameter along which the respective vibrator 37 is located.
- the plate 39 is resiliently mounted to the cylindrical outer enmetal and an outer second tubular envelope spaced therefrom with means connecting the extremities of the first and second envelopes to create a fiuidtight annular space therebetween.
- a third tubular envelope is closely spaced in relation to the first tubular envelope to provide a narrow fluid channel for the flow of cooling fluid.
- Vibrators are mounted outside of and adjacent the second envelope and have rodlike pistons extending through the second and third envelopes and into contact with BRIEF DESCRIPTION OF THE DRAWING in the drawing:
- FIG. 1 is a vertical sectional view of a continuous casting mold in accordance with the invention
- FIG. 2 is a sectional view along line 11-11 of FIG. 1;
- FIG. 3 is a sectional view along line III-III of FIG. 1.
- a continuous casting mold 11 in accordance with the invention includes an outer cylindrical envelope l3 and spaced apart inner and outer rectangular tubular envelopes 15, 17, respectively, disposed coaxially within the outer cylindrical envelope 13. From FIG. 1 it will be noted that the outer cylindrical envelope is provided with top 19 and bottom 21 flanges that are also secured to the inner rectangular tubular envelope 15. Thus, an annular space 23 is created for fluid return from cooling the mold wall, which is what the inner rectangular tubultlr envelope 15 actually is.
- the outer rectangular tubular envelope 17 is spaced from, but closely adjacent to, the mold wall 15 and is suitably held concentric thereto at strategic locations, such as at 25, 27.
- the outer rectangular envelope 17 is spaced apart from both the top 19 and the bottom 21 flanges, wherefore fluid flows in the annulus 29 between the mold wall 15 and the outer rectangular envelope 17.
- annular space23 Near the bottom of the cylindrical outer envelope 13, there is a horizontally arranged diaphragm 31 that divides the annular space23 into an upper annular space 23a and a lower annular space 23b.
- An O-ring gasket 33 is mounted in the inner velope 13 at its top and bottom extremities.
- Each vertical rectangular plate 39 abuts the outer ends of spaced rodlike pistons 41 which extend through axially aligned apertures in both the cylindrical outer envelope l3 and the outer rectangular envelope l7.
- O-ring gaskets 43 are provided to seal the pistons 41 where they pass through the cylindrical outer envelope 13, and the outer rectangular envelope, 17.
- the inner end 45 of each piston 41 contacts the outer surface of the mold wall 15, but does not pierce the mold wall 15.
- each rodlike piston 41 is bifurcated, as shown in FIG. 3; that is to say, a vertical groove 49, formed in the end 45, has a throat area 51 and divergent-convergent walls 53, 55 leading respectively toward and away from the throat area 5!.
- Suitable fasteners 57 secure the rodlike pistons 41 to the vertical plate 39 wherefore, when the vibrators 37 are actuated, both the vertical plate 39 and the rodlike pistons 41 vibrate.
- the rodlike pistons 41 then beat rapidly upon the mold wall 15 and it, in turn, vibrates and beats upon the skin of a continuous cast strand being formed of molten metal that is being poured into the mold 15.
- a feature of the invention is that a continuous casting having a supersmooth exterior surface can be readily attained, and that it is not necessary to have a mold of specific length and size to be able to continuously cast metal, such as rimming steel, with its boiling'action, in order to produce a continuous casting with an acceptable and supersmooth exterior surface.
- a feature of the invention is that a continuous-cast strand is produced in the mold of the invention that has a higher quality and improved crystalline structure throughout the cast strand.
- a feature of the invention is that the mold walls may be vibrated when it would be advantageous to do so, and may not be vibrated when different kinds of metal are being cast and it is disadvantageous to vibrate the walls of the mold.
- a mold for forming a continuous-cast strand of molten metal comprising:
- a third tubular envelope mounted in said annular space and in close spaced relation to said first tubular envelop whereby a second narrow annulus is created between said first and third tubular envelopes;
- said vibratory means includes: i. a powered vibrator having ii. rodlike pistons connected thereto and extending through apertures in the second and third envelopes; and b. means to seal and prevent fluid from flowing through the annular spaces between said pistons and said apertures.
- a support resiliently mounted in spaced relation to said second tubular envelope said support being a mounting for at least one said vibrator with said rodlike pistons being fixed to said support.
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Continuous Casting (AREA)
Abstract
A continuous-casting mold is equipped with individual vibratory units that rapidly impact the mold wall and cause the mold wall to vibrate against the cast strand thereby improving the crystalline and surface structure of the cast strand.
Description
United States Patent Inventor Joseph J. Ciochetto Allison Park, Pa. (c/o Koppers Co. Inc., 440 College Park Drive, Monroeville, Pa. 15146) Appl. No. 772,900
Filed Nov. 4, 1968 Patented Feb. 23, 1971 CONTINUOUS-CASTING MOLD 3 Claims, 3 Drawing Figs.
11.8. CI. 164/273, 164/260, 164/83 Int. Cl 822d 1 1/00 Field of Search 164/83, 260, 261, 89, 66, 273, 48, 49, 283
References Cited UNITED STATES PATENTS '2/1970 Reihman 164/83 3,447,587 6/1969 Bodine, Jr.- 164/260X 3,447,480 6/1969 Bodine Jr. 164/49 FOREIGN PATENTS 1,031,135 3/1953 France.
500,794 2/1951 Belgium 699,156 10/1953 01661131113111. 178,432 5/1954 Australia.
Primary ExaminerCharles W. Lanham Assistant ExaminerV.K. Rising Attorneys-Sherman l-l. Barber and Olin E. Williams ABSTRACT: A continuous-casting mold is equipped with individual vibratory units that rapidly impact the mold Wall and cause the mold wall to vibrate against the cast strand thereby improving the crystalline and surface structure of the cast strand.
PATENTEU F552 1911 3.565.158
7 sum 1 OF 2- INVENTOR. J0$PH J. CIDCHETTO FIG-.2.
INVENTOR. Jase-PH J. .clocmsrro sum 2 0F 2 PATENTEUFEBEBIBYI wwuzw 1 continuous-CASTING MOLD BACKGROUND OF THE INVENTION This invention relates to continuous casting and, more particularly, to apparatus for vibrating the walls of the continuous-casting mold.
I-leretofore, in continuous-casting machines, molds have been vibrated to reduce the tendency of the cast strand, while it is being formed in the mold, to stick to the walls of the mold. U.S. Pat. No. 2,284,703 to A. Welblund et al. That issued June 2, 1942, for example, discloses a continuous-casting mold made into sections each of which sections is given a relatively slight, but rapid vibration transversely to the direction of motion of the casting. Such vibration is alleged to prevent sticking or adherence to the solidifying skin of the casting to the walls of the mold.
The present invention, however, discloses a novel and improved mold, which is equipped'with vibratory apparatus that produces a continuous-cast strand having greatly improved metallurgical structure.
SUMMARY OF THE INVENTION periphery of the diaphragm to provide a seal against the flow of fluid directly past the diaphragm 31 from the annular space 230 into the annular space 23b, or vice versa.
Cooling water flows into the lower annular space 23b and into the annulus 29. Thence, the cooling water courses upward to the top of theannulus 29, and into the upper annular space 230. Fluid discharge openings 35 are provided at the bottom of the upper annular space 23a to discharge the cooling water.
The cylindrical outer envelope 13 supports four resiliently mounted vibrators 37 that are disposed at the ends of diameters that are both mutually perpendicular and perpendicular to the four walls of the mold 15. The vibrators 37 may be of any suitable type having a range of frequencies between 700 and l,500 c.p.s. and an amplitude of between two-thousandths and eight-thousandths of an inch.
Each vibrator 37 is mounted to a vertical, rectangular plate 39 spaced apart from and disposed perpendicularly to the diameter along which the respective vibrator 37 is located.
- .The plate 39 is resiliently mounted to the cylindrical outer enmetal and an outer second tubular envelope spaced therefrom with means connecting the extremities of the first and second envelopes to create a fiuidtight annular space therebetween. A third tubular envelope is closely spaced in relation to the first tubular envelope to provide a narrow fluid channel for the flow of cooling fluid. Vibrators are mounted outside of and adjacent the second envelope and have rodlike pistons extending through the second and third envelopes and into contact with BRIEF DESCRIPTION OF THE DRAWING in the drawing:
FIG. 1 is a vertical sectional view of a continuous casting mold in accordance with the invention;
FIG. 2 is a sectional view along line 11-11 of FIG. 1; and
FIG. 3is a sectional view along line III-III of FIG. 1.
DETAILED DESCRIPTION A continuous casting mold 11 in accordance with the invention includes an outer cylindrical envelope l3 and spaced apart inner and outer rectangular tubular envelopes 15, 17, respectively, disposed coaxially within the outer cylindrical envelope 13. From FIG. 1 it will be noted that the outer cylindrical envelope is provided with top 19 and bottom 21 flanges that are also secured to the inner rectangular tubular envelope 15. Thus, an annular space 23 is created for fluid return from cooling the mold wall, which is what the inner rectangular tubultlr envelope 15 actually is. The outer rectangular tubular envelope 17 is spaced from, but closely adjacent to, the mold wall 15 and is suitably held concentric thereto at strategic locations, such as at 25, 27. The outer rectangular envelope 17 is spaced apart from both the top 19 and the bottom 21 flanges, wherefore fluid flows in the annulus 29 between the mold wall 15 and the outer rectangular envelope 17.
Near the bottom of the cylindrical outer envelope 13, there is a horizontally arranged diaphragm 31 that divides the annular space23 into an upper annular space 23a and a lower annular space 23b. An O-ring gasket 33 is mounted in the inner velope 13 at its top and bottom extremities.
Each vertical rectangular plate 39 abuts the outer ends of spaced rodlike pistons 41 which extend through axially aligned apertures in both the cylindrical outer envelope l3 and the outer rectangular envelope l7. O-ring gaskets 43 are provided to seal the pistons 41 where they pass through the cylindrical outer envelope 13, and the outer rectangular envelope, 17. The inner end 45 of each piston 41 contacts the outer surface of the mold wall 15, but does not pierce the mold wall 15.
The end 45 of each rodlike piston 41 is bifurcated, as shown in FIG. 3; that is to say, a vertical groove 49, formed in the end 45, has a throat area 51 and divergent-convergent walls 53, 55 leading respectively toward and away from the throat area 5!.
Because of the resilient mounting of the vertical plate 39 to the cylindrical outer envelope 13, the cylindrical outer envelope itselfdoes not vibrate.
Heretofore, it has not been possible to satisfactorily produce continuous cast strands of rimming grade steel, which has a chemistry that causes the molten metal to boil as the steel solidifies. This boiling action causes the clean particles or molecules of the outer surfaces of the casting to arrange themselves in a rim" which provides a supersmooth exterior surface. Those skilled in the art will recognize, however, that the vibrating mold of the present invention, which has numerous horizontal members contacting the mold walls on all four sides in a zone adjacent the upper portion of the mold where molten metal first starts to crystallize, will cause the molecules at the outer surface of the casting to arrange themselves in a fine crystallization form due to the external vibrating forces applied to the mold wall and to the casting.
A feature of the invention is that a continuous casting having a supersmooth exterior surface can be readily attained, and that it is not necessary to have a mold of specific length and size to be able to continuously cast metal, such as rimming steel, with its boiling'action, in order to produce a continuous casting with an acceptable and supersmooth exterior surface.
A feature of the invention is that a continuous-cast strand is produced in the mold of the invention that has a higher quality and improved crystalline structure throughout the cast strand.
A feature of the invention is that the mold walls may be vibrated when it would be advantageous to do so, and may not be vibrated when different kinds of metal are being cast and it is disadvantageous to vibrate the walls of the mold.
Although the invention has been described herein with a certain degree of particularity, it is to be understood that the present disclosure has been made only as an example and that the scope of the invention is defined by what is hereinafter claimed.
I claim:
1. A mold for forming a continuous-cast strand of molten metal comprising:
a. an inner first tubular envelope defining a mold cavity for receiving molten metal;
b. an outer second tubular envelope surrounding said first tubular envelope in spaced apart relation;
0. means connecting the extremities of said first and second envelopes to create a fluidtight first annular space therebetween;
d. a third tubular envelope mounted in said annular space and in close spaced relation to said first tubular envelop whereby a second narrow annulus is created between said first and third tubular envelopes;
e. a diaphragm extending across and subdividing the annular space between the third and second envelopes into third and fourth fluidtight annular spaces;
f. means to introduce cooling fluid into the third annular space whereby said fluid courses the second annular space and thereafter flows into said fourth annular space; g. means to remove said cooling fluid from said fourth annular space; and h. vibratory means mounted adjacent said second envelope and having means extending through said second envelope so as to contact said first envelope whereby, when said vibratory means is actuated, said first envelope vibrates against said cast strand. 2. The invention of claim 1 wherein: a. said vibratory means includes: i. a powered vibrator having ii. rodlike pistons connected thereto and extending through apertures in the second and third envelopes; and b. means to seal and prevent fluid from flowing through the annular spaces between said pistons and said apertures. 3. The invention of claim 2 including a support resiliently mounted in spaced relation to said second tubular envelope, said support being a mounting for at least one said vibrator with said rodlike pistons being fixed to said support.
UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No, 565,158 Dated February 23 1971 Joseph J. Ciochetto Inventor(s) It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:
On the cover sheet [72] cancel "(c/o Koppers Co. Inc 440 College Park Drive, Monroeville, Pa. 15146)" and insert assignor to Koppers Company, Inc., a corporation of Delaware r Signed and sealed this 8th day of June 1971 (SEAL) Attest:
WILLIAM E. SCHUYLER, J
EDWARD M.FLETCHER,JR.
Commissioner of Patent Attesting Officer
Claims (3)
1. A mold for forming a continuous-cast strand of molten metal comprising: a. an inner first tubular envelope defining a mold cavity for receiving molten metal; b. an outer second tubular envelope surrounding said first tubular envelope in spaced apart relation; c. means connecting the extremities of said first and second envelopes to create a fluidtight first annular space therebetween; d. a third tubular envelope mounted in said annular space and in close spaced relation to said first tubular envelop whereby a second narrow annulus is created between said first and third tubular envelopes; e. a diaphragm extending across and subdividing the annular space between the third and second envelopes into third and fourth fluidtight annular spaces; f. means to introduce cooling fluid into the third annular space whereby said fluid courses the second annular space and thereafter flows into said fourth annular space; g. means to remove said cooling fluid from said fourth annular space; and h. vibratory means mounted adjacent said second envelope and having means extending through said second envelope so as to contact said first envelope whereby, when said vibratory means is actuated, said first envelope vibrates against said cast strand.
2. The invention of claim 1 wherein: a. said vibratory means includes: i. a powered vibrator having ii. rodlike pistons connected thereto and extending through apertures in the second and third envelopes; and b. means to seal and prevent fluid from flowing through the annular spaces between said pistons and said apertures.
3. The invention of claim 2 including a support resiliently mounted in spaced relation to said second tubular envelope, said support being a mounting for at least one said vibrator with said rodlike pistons being fixed to said support.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US77290068A | 1968-11-04 | 1968-11-04 |
Publications (1)
Publication Number | Publication Date |
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US3565158A true US3565158A (en) | 1971-02-23 |
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US772900A Expired - Lifetime US3565158A (en) | 1968-11-04 | 1968-11-04 | Continuous-casting mold |
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Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3667534A (en) * | 1971-03-11 | 1972-06-06 | Sumitomo Metal Ind | Steel ingot making method |
US3794105A (en) * | 1971-06-01 | 1974-02-26 | Demag Ag | Oscillating wall arrangement for a continuous casting mold |
FR2471821A1 (en) * | 1979-12-21 | 1981-06-26 | Nippon Kokan Kk | CONTINUOUS CASTING MOLD OF STEEL EQUIPPED WITH ULTRASONIC VIBRATORS |
WO1983003214A1 (en) * | 1982-03-18 | 1983-09-29 | Lansdown, Anthony, Richard | The use of a hydraulic squeeze film to lubricate the strand in continuous casting |
US4691757A (en) * | 1984-05-10 | 1987-09-08 | Voest-Alpine Aktiengesellschaft | Arrangement provided at a continuous casting plant |
US4807691A (en) * | 1982-02-27 | 1989-02-28 | Mannesmann Ag | Mold for continuous casting of metal |
WO1995003904A1 (en) * | 1993-07-30 | 1995-02-09 | Paul Wurth S.A. | Continuous casting ingot mould |
Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
BE500794A (en) * | ||||
FR1031135A (en) * | 1951-01-18 | 1953-06-19 | Advanced Metal Casting Process | |
GB699156A (en) * | 1950-09-05 | 1953-10-28 | Siegfried Junghans | Method of and installation for casting metals |
US3447480A (en) * | 1967-07-24 | 1969-06-03 | Bodine Albert G | Method and apparatus for gravity flow casting utilizing sonic energization |
US3447587A (en) * | 1967-07-24 | 1969-06-03 | Bodine Albert G | Method and device for mold casting utilizing sonic energization |
US3494411A (en) * | 1965-10-06 | 1970-02-10 | Bethlehem Steel Corp | Continuous casting method |
-
1968
- 1968-11-04 US US772900A patent/US3565158A/en not_active Expired - Lifetime
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
BE500794A (en) * | ||||
GB699156A (en) * | 1950-09-05 | 1953-10-28 | Siegfried Junghans | Method of and installation for casting metals |
FR1031135A (en) * | 1951-01-18 | 1953-06-19 | Advanced Metal Casting Process | |
US3494411A (en) * | 1965-10-06 | 1970-02-10 | Bethlehem Steel Corp | Continuous casting method |
US3447480A (en) * | 1967-07-24 | 1969-06-03 | Bodine Albert G | Method and apparatus for gravity flow casting utilizing sonic energization |
US3447587A (en) * | 1967-07-24 | 1969-06-03 | Bodine Albert G | Method and device for mold casting utilizing sonic energization |
Cited By (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3667534A (en) * | 1971-03-11 | 1972-06-06 | Sumitomo Metal Ind | Steel ingot making method |
US3794105A (en) * | 1971-06-01 | 1974-02-26 | Demag Ag | Oscillating wall arrangement for a continuous casting mold |
FR2471821A1 (en) * | 1979-12-21 | 1981-06-26 | Nippon Kokan Kk | CONTINUOUS CASTING MOLD OF STEEL EQUIPPED WITH ULTRASONIC VIBRATORS |
US4807691A (en) * | 1982-02-27 | 1989-02-28 | Mannesmann Ag | Mold for continuous casting of metal |
WO1983003214A1 (en) * | 1982-03-18 | 1983-09-29 | Lansdown, Anthony, Richard | The use of a hydraulic squeeze film to lubricate the strand in continuous casting |
US4691757A (en) * | 1984-05-10 | 1987-09-08 | Voest-Alpine Aktiengesellschaft | Arrangement provided at a continuous casting plant |
WO1995003904A1 (en) * | 1993-07-30 | 1995-02-09 | Paul Wurth S.A. | Continuous casting ingot mould |
CN1042404C (en) * | 1993-07-30 | 1999-03-10 | 保尔.沃特公司 | Continuous casting ingot mould |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: RAYMOND KAISER ENGINEERS INC., OAKLAND CALIFORNIA Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:KOPPERS COMPANY, INC.;REEL/FRAME:004292/0615 Effective date: 19840503 |