CN108480609B - Continuous casting prevents blockking up immersion nozzle - Google Patents
Continuous casting prevents blockking up immersion nozzle Download PDFInfo
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- CN108480609B CN108480609B CN201810295473.7A CN201810295473A CN108480609B CN 108480609 B CN108480609 B CN 108480609B CN 201810295473 A CN201810295473 A CN 201810295473A CN 108480609 B CN108480609 B CN 108480609B
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- Prior art keywords
- hole
- side hole
- holes
- arc
- elliptical
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- 238000009749 continuous casting Methods 0.000 title claims abstract description 20
- 238000007654 immersion Methods 0.000 title description 14
- 229910000831 Steel Inorganic materials 0.000 abstract description 17
- 239000010959 steel Substances 0.000 abstract description 17
- 230000024121 nodulation Effects 0.000 description 5
- 238000004519 manufacturing process Methods 0.000 description 4
- 238000005266 casting Methods 0.000 description 3
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 2
- 229910052782 aluminium Inorganic materials 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 229910001200 Ferrotitanium Inorganic materials 0.000 description 1
- 229910000655 Killed steel Inorganic materials 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000000903 blocking effect Effects 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000008187 granular material Substances 0.000 description 1
- 229910052761 rare earth metal Inorganic materials 0.000 description 1
- 150000002910 rare earth metals Chemical class 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
- B22D41/00—Casting melt-holding vessels, e.g. ladles, tundishes, cups or the like
- B22D41/50—Pouring-nozzles
Abstract
The invention belongs to the field of high-temperature molten steel continuous casting, and relates to an anti-clogging submerged nozzle for continuous casting, which comprises a body, a main hole and side holes, wherein the main hole is positioned inside the body, the side holes are positioned on two sides of the body and are communicated with the main hole, at least one pair of side holes are designed in such a way that two side walls are outwards expanded in an arc shape with an angle of α or R as a radius, the bottom of each side hole is downwards expanded in an arc shape with R as a radius and forms a lower side hole of the submerged nozzle with the top of the side hole with a downward angle b.
Description
Technical Field
The invention belongs to the field of high-temperature molten steel continuous casting, and relates to an anti-blocking submerged nozzle for continuous casting.
Background
In the continuous casting production of high-temperature molten steel, particularly in the continuous casting of molten steel of low-carbon aluminum killed steel, steel with high aluminum content, steel containing rare earth and steel containing titanium steel, because more non-metallic inclusions exist in the molten steel, in the process that the molten steel containing small non-metallic inclusions enters a crystallizer through a submerged nozzle from a continuous casting tundish, the inclusions in the molten steel are adhered to the side wall of a straight-wall type side hole at the lower part of the submerged nozzle, along with the progress of molten steel casting, the number of the inclusions adhered to the side wall of the side hole at the lower part of the submerged nozzle is gradually increased to form nodules, so that the sectional area of the side hole of the submerged nozzle is reduced, and the side hole is blocked. The nodulation and blockage of the submerged nozzle can cause the reduction of continuous casting speed and even stop casting, thereby influencing continuous casting production. Therefore, people are dedicated to solving the problem of blocking up of the immersion nozzle of continuous casting molten steel all the time, and some adoption changes immersion nozzle bottom structure, and some proposals set up at immersion nozzle owner hole inner wall and prevent stifled inner wall, and some increase at the immersion nozzle owner hole prevents stifled edges, some inner structure who changes the immersion nozzle owner hole. But the technical scheme can not solve the problems of side hole nodulation and blockage of the conventional submerged nozzle.
Disclosure of Invention
The invention aims to solve the technical problems of nodulation and blockage of the side hole of the submerged nozzle during the continuous casting of molten steel of plate blanks, large square blanks and large round blanks, and avoid the adhesion of non-metallic inclusions in the molten steel on the side wall of the side hole of the submerged nozzle to form nodulation and blockage of the nozzle.
The technical scheme of the invention is as follows:
an anti-blocking immersion nozzle for continuous casting comprises a body 1, a main hole 2 and a side hole 3; the main hole 2 is positioned in the body 1, and the side holes 3 are positioned on two sides of the body 1 and communicated with the main hole 2; and at least one pair of side holes 3 are formed.
The side hole comprises a side hole bottom 4, an arc edge 5, a straight edge 6 and an arc radius R, wherein the side hole bottom 4 is a lower bottom edge of the side hole 3, the side hole top 7 is an upper bottom edge of the side hole 3, the arc edge 5 is an arc edge formed by outward expansion of the side wall of the side hole 3 by the angle R, the straight edge 6 is a straight edge formed by outward expansion of the side wall of the side hole 3 by the angle α, α is an expansion angle of the side wall of the side hole 3, R is an arc radius of the side wall of the side hole 3, and.
The two side walls of the side hole 3 are outwardly expanded with the straight edge 6 of the angle α, the bottom 4 of the side hole is downwardly expanded with the arc of radius R, and the top 7 of the side hole with the downward angle b constitutes the lower side hole of the submerged nozzle, wherein 0 < α <60 °, 10 < R <500mm, and 0 < b <30 °.
The two side walls of the side hole 3 are outwardly expanded by an arc edge 5 with R as a radius, the bottom 4 of the side hole is downwardly expanded by an arc with R as a radius, and the top 7 of the side hole with a downward angle b forms a lower side hole of the submerged nozzle, wherein R is less than 10mm and is less than 500mm, R is less than 10mm and is less than 500mm, and b is less than 0 degree and is less than 30 degrees.
The side hole 3 is one of a rectangular hole, an elliptical hole or a quasi-elliptical hole; the two sides of the quasi-elliptical hole are straight lines.
When the side hole 3 is a pair of rectangles, α is 20 °, R is 50mm, and b is 15 °.
When the side hole 3 is a pair of rectangles, R is 50mm, R is 60mm, and b is 14 °.
When the side hole 3 is a pair of elliptical holes, α is 30 °, R is 40mm, and b is 15 °.
When the side hole 3 is a pair of elliptical holes, R is 45mm, R is 55mm, and b is 13 °.
When the side hole 3 is an aligned elliptical hole, α is 25 °, R is 60mm, and b is 16 °.
When the side hole 3 is an aligned elliptical hole, R is 55mm, R is 45mm, and b is 16 °.
When the side hole 3 is two pairs of rectangles, α is 23 °, R is 50mm, and b is 14 °.
When the side holes 3 are two pairs of rectangles, R is 55mm, and b is 15 °.
When the side hole 3 is two pairs of elliptical holes, α is 28 degrees, R is 48mm, and b is 12 degrees.
When the side hole 3 is two pairs of elliptical holes, R is 60mm, R is 55mm, and b is 16 °.
When the side hole 3 is two aligned elliptical holes, α is 50 °, R is 50mm, and b is 15 °.
When the side hole 3 is two aligned elliptical holes, R is 50mm, R is 60mm, and b is 13 °.
The invention has the beneficial effects that: the side hole that designs into the gradual expansion through the side hole with immersion nozzle lower part makes the molten steel flow through the in-process of immersion nozzle side hole, and under the effect of inertial force, the non-metallic inclusion granule in the molten steel directly flows out the side hole of immersion nozzle, can avoid the non-metallic inclusion in the molten steel and the lateral wall of immersion nozzle side hole to bump the contact to prevent the inclusion adhesion on the lateral wall of side hole, effectively prevent nodulation and the jam phenomenon of immersion nozzle side hole. The submerged nozzle with the structure has the advantages of simple structure, easiness in manufacturing, capability of improving the quality of a casting blank and capability of ensuring the smooth continuous casting production.
Drawings
FIG. 1 is a schematic view showing a conventional submerged entry nozzle having two side holes.
FIG. 2 is a view of the submerged entry nozzle of FIG. 1 taken along the line A-A.
FIG. 3 is a side view of the submerged entry nozzle of FIG. 1.
Fig. 4 is a schematic view of a submerged entry nozzle according to embodiment 1 of the present invention.
Fig. 5 is a side view of fig. 4.
Fig. 6 is a view from a-a of fig. 4.
FIG. 7 is a view of the side hole of the submerged nozzle of FIG. 4 in the direction A-A of the arc-shaped side wall.
Fig. 8 is a schematic view of a submerged entry nozzle according to embodiment 2 of the present invention.
Fig. 9 is a schematic view of a submerged entry nozzle according to embodiment 3 of the present invention.
Fig. 10 is a schematic view of a submerged entry nozzle according to embodiment 4 of the present invention.
Fig. 11 is a schematic view of a submerged entry nozzle according to embodiment 5 of the present invention.
Fig. 12 is a schematic view of a submerged entry nozzle according to embodiment 6 of the present invention.
Fig. 13 is a view taken along line a-a of fig. 10-12.
FIG. 14 is a view of the side hole of the submerged nozzle of FIGS. 10 to 12 in the direction A-A of the arc-shaped side wall.
In the figure, a main body 1, a main hole 2, a side hole 3, a side hole bottom 4, an arc edge 5, a straight edge 6, a side hole top 7, α which is a divergence angle of the side wall of the side hole, R which is the arc radius of the side wall of the side hole and R which is the arc radius of the bottom of the side hole are shown.
Detailed Description
The following detailed description of specific embodiments of the present invention is provided in connection with the accompanying drawings.
A novel prevent blockking up immersion nozzle for slab continuous casting:
example 1
As shown in fig. 4, 5 and 6, the anti-clogging submerged nozzle of the present invention has two side holes 3 of a rectangular shape, which is composed of a body 1, a main hole 2 and two rectangular holes 3 at the lower part of the side walls of the body, and the two side walls of the rectangular holes are outwardly expanded by a straight edge 6 having an angle α of 20 °, as shown in fig. 6.
The side hole bottom 4 is downwardly flared in an arc shape with a radius of R50 mm and forms a lower side hole of the submerged entry nozzle with the side hole top 7 having a downward angle b of 15 °, as shown in fig. 4.
Example 2
As shown in fig. 4, 5 and 7, the two side holes 3 of the anti-clogging submerged nozzle of the present invention are rectangular. The submerged nozzle is composed of a body 1, a main hole 2 and two rectangular side holes 3 at the lower part of the side wall of the body, the two side walls of the rectangular hole are outwardly expanded by an arc-shaped side 5 (fig. 7) with a radius R of 50mm, a side hole bottom 4 (fig. 4) is downwardly expanded by an arc-shaped side with a radius R of 60mm, and a side hole top 7 (fig. 4) with a downward angle b of 14 ° forms the lower side hole of the submerged nozzle.
Example 3
As shown in fig. 4, 8 and 6, the anti-clogging submerged nozzle of the present invention has two oval side holes 3 at the lower part, which are composed of a body 1, a main hole 2 and two oval holes 3 at the lower part of the side wall of the body, the two side walls of the oval holes are outwardly expanded by a straight edge 6 (fig. 6) having an angle α of 30 °, the bottom 4 (fig. 4) of the side hole is downwardly expanded by an arc having a radius R of 40mm, and the side hole top 7 (fig. 4) having a downward angle b of 15 ° forms the lower side hole of the submerged nozzle.
Example 4
As shown in fig. 4, 8 and 7, the two side holes 3 at the lower part of the anti-clogging submerged nozzle of the present invention are oval. The submerged nozzle is composed of a body 1, a main hole 2 and two elliptical holes 3 at the lower part of the side wall of the body, the two side walls of the elliptical holes are outwardly expanded by an arc-shaped edge 5 (figure 7) with a radius of R-45 mm, a side hole bottom 4 (figure 4) is downwardly expanded by an arc with a radius of R-55 mm, and a side hole top 7 (figure 4) with a downward angle b of 13 ° forms a lower side hole of the submerged nozzle.
Example 5
As shown in fig. 4, 9 and 5, the anti-clogging submerged nozzle of the present invention has two side holes 3 in a quasi-elliptical shape, i.e., two sides of the quasi-elliptical shape are straight lines and upper and lower sides are circular arcs, the submerged nozzle is composed of a body 1, a main hole 2 and two quasi-elliptical holes 3 at the lower part of the side wall of the body, two side walls of the quasi-elliptical holes are outwardly expanded by a straight edge 6 (fig. 6) with an angle α of 25 °, and a side hole bottom 4 (fig. 4) is downwardly expanded by an arc with a radius of R60 and forms a lower side hole of the submerged nozzle with a side hole top 7 (fig. 4) with a downward angle b of 16 °.
The anti-blocking submerged nozzle for continuous casting of the bloom or large round billet comprises the following components:
example 7
As shown in fig. 10 and 13, the anti-clogging submerged nozzle of the present invention has 4 side holes 3 in a rectangular shape, which are composed of a main body 1, a main hole 2, and 4 rectangular holes 3 in the lower portion of the side wall of the main body, two side walls of the rectangular holes are outwardly expanded by a straight edge 6 (fig. 13) having an angle α ═ 23 °, a side hole bottom 4 (fig. 10) is downwardly expanded by an arc having a radius R ═ 50mm, and a side hole top 7 (fig. 10) having a downward angle b ═ 14 ° forms a lower side hole of the submerged nozzle.
Example 8
As shown in fig. 10 and 14, the anti-clogging submerged nozzle of the present invention has 4 side holes 3 in rectangular shape. The submerged nozzle is composed of a body 1, a main hole 2 and two rectangular side holes 3 at the lower part of the side wall of the body, the two side walls of the rectangular hole are outwardly expanded by an arc-shaped edge 5 (figure 13) with a radius of R-55 mm, a side hole bottom 4 (figure 10) is downwardly expanded by an arc with a radius of R-55 mm, and the side hole bottom and a side hole top 7 (figure 10) with a downward angle b of 15 DEG form the lower side hole of the submerged nozzle.
Example 9
As shown in fig. 11 and 13, the anti-clogging submerged nozzle of the present invention has 4 side holes 3 in an elliptical shape, and the submerged nozzle is composed of a main body 1, a main hole 2, and 4 elliptical holes 3 in the lower portion of the side wall of the main body, both side walls of the elliptical holes are outwardly expanded by a straight edge 6 (fig. 13) having an angle α of 28 °, and a side hole bottom 4 (fig. 11) is downwardly expanded by an arc having a radius R of 48mm, and forms a lower side hole of the submerged nozzle with a side hole top 7 (fig. 11) having a downward angle b of 12 °.
Example 10
As shown in fig. 11 and 14, the anti-clogging submerged nozzle of the present invention has 4 side holes 3 in an elliptical shape. The submerged nozzle comprises a body 1, a main hole 2 and 4 elliptical side holes 3 at the lower part of the side wall of the body, wherein two side walls of the elliptical hole are outwards expanded by an arc-shaped edge 5 (figure 14) with the radius of R being 60mm, the bottom part 4 (figure 11) of the side hole is downwards expanded by an arc-shaped edge with the radius of R being 55mm, and the side hole and the top part 7 (figure 11) of the side hole with the downward angle b being 16 degrees form the lower side hole of the submerged nozzle.
Example 11
As shown in fig. 12 and 13, the anti-clogging submerged nozzle of the present invention has 4 side holes 3 in a quasi-elliptical shape, which consists of a body 1, a main hole 2 and 4 elliptical holes 3 in the lower part of the side wall of the body, two side walls of the elliptical holes are outwardly expanded by a straight edge 6 (fig. 13) having an angle α of 50 °, a side hole bottom 4 (fig. 12) is downwardly expanded by an arc having a radius R of 50mm, and a side hole top 7 (fig. 12) having a downward angle b of 15 ° forms a lower side hole of the submerged nozzle.
Example 12
As shown in fig. 12 and 14, the anti-clogging submerged nozzle of the present invention has the 4 side holes 3 in a quasi-elliptical shape. The submerged nozzle comprises a body 1, a main hole 2 and 4 elliptical side holes 3 at the lower part of the side wall of the body, wherein two side walls of the elliptical hole are outwards expanded by an arc-shaped edge 5 (figure 14) with the radius of R being 50mm, the bottom part 4 (figure 12) of the side hole is downwards expanded by an arc-shaped edge with the radius of R being 60mm, and the side hole and a side hole top part 7 (figure 12) with the downward angle b being 13 degrees form a lower side hole of the submerged nozzle.
Claims (3)
1. The continuous casting anti-blocking submerged nozzle is characterized by comprising a body (1), a main hole (2) and a side hole (3); the main hole (2) is positioned inside the body (1), and the side holes (3) are positioned on two sides of the body (1) and communicated with the main hole (2); the number of the side holes (3) is not less than one;
the bottom (4) of the side hole is the lower bottom edge of the side hole (3); the top (7) of the side hole is the upper bottom edge of the side hole (3), and the arc-shaped edge (5) is an arc-shaped edge formed by outward expansion of the side wall of the side hole (3) by taking r as a reference; wherein r is the arc radius of the side wall of the side hole (3); r is the arc radius of the bottom (4) of the side hole;
the side hole (3) is one of a rectangular hole, an elliptical hole or a quasi-elliptical hole;
the two side walls of the side hole (3) are expanded outwards by the arc-shaped edge (5) taking r as the radius, namely the arc-shaped convex wall; the bottom (4) of the side hole is downwardly flared in an arc with radius R, and forms a lower side hole of the submerged nozzle with the top (7) of the side hole at a downward angle b, wherein 10mm < R <500mm, 10mm < R <500mm, 0 < b <30 °.
2. The continuous casting anti-clogging submerged entry nozzle according to claim 1, characterized in that when said side holes (3) are a pair of rectangles, R =50mm, R =60mm, b =14 °; when the side hole (3) is a pair of elliptical holes, R =45mm, R =55mm, b =13 °; when the side hole (3) is an aligned elliptical hole, R =55mm, R =45mm, and b =16 °.
3. Anti-clogging submerged entry nozzle for continuous casting according to claim 1, characterized in that when said lateral holes (3) are two pairs of rectangles, R =55mm, b =15 °; when the side holes (3) are two pairs of elliptical holes, R =60mm, R =55mm, and b =16 °; when the side hole (3) is two aligned elliptical holes, R =50mm, R =60mm, and b =13 °.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810295473.7A CN108480609B (en) | 2018-03-30 | 2018-03-30 | Continuous casting prevents blockking up immersion nozzle |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810295473.7A CN108480609B (en) | 2018-03-30 | 2018-03-30 | Continuous casting prevents blockking up immersion nozzle |
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| Publication Number | Publication Date |
|---|---|
| CN108480609A CN108480609A (en) | 2018-09-04 |
| CN108480609B true CN108480609B (en) | 2020-02-11 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810295473.7A Expired - Fee Related CN108480609B (en) | 2018-03-30 | 2018-03-30 | Continuous casting prevents blockking up immersion nozzle |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN111906266B (en) * | 2020-08-21 | 2021-11-30 | 北京科技大学 | Method for inhibiting rare earth molten steel pouring nozzle from being blocked by pulse current |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103212682A (en) * | 2013-04-25 | 2013-07-24 | 沈阳东大新冶金技术有限公司 | Submersed nozzle for plate blank electromagnetic rotational flow continuous casting |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2607214Y (en) * | 2003-02-19 | 2004-03-24 | 鞍山钢铁集团公司 | Immersed nozzle for continuous casting mould |
| CN200991751Y (en) * | 2006-12-28 | 2007-12-19 | 鞍钢股份有限公司 | Four-hole immersible water-gap for large-square blank continuous casting |
| JP4665056B1 (en) * | 2010-03-31 | 2011-04-06 | 黒崎播磨株式会社 | Immersion nozzle |
| CN202527702U (en) * | 2012-01-18 | 2012-11-14 | 中冶南方工程技术有限公司 | Submersed nozzle for continuous bloom casting mold |
| JP5451868B2 (en) * | 2012-04-26 | 2014-03-26 | 品川リフラクトリーズ株式会社 | Immersion nozzle for continuous casting equipment |
| CN202639321U (en) * | 2012-06-07 | 2013-01-02 | 武汉钢铁(集团)公司 | Crystallizer immersion water gap used for heavy rail steel production |
| CN203330395U (en) * | 2013-03-27 | 2013-12-11 | 鞍钢股份有限公司 | Anti-blocking submersed nozzle for continuous casting of sheet billet |
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Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103212682A (en) * | 2013-04-25 | 2013-07-24 | 沈阳东大新冶金技术有限公司 | Submersed nozzle for plate blank electromagnetic rotational flow continuous casting |
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