KR101705588B1 - Immersion vessel structure of vacuum degassing system - Google Patents

Immersion vessel structure of vacuum degassing system Download PDF

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Publication number
KR101705588B1
KR101705588B1 KR1020150070272A KR20150070272A KR101705588B1 KR 101705588 B1 KR101705588 B1 KR 101705588B1 KR 1020150070272 A KR1020150070272 A KR 1020150070272A KR 20150070272 A KR20150070272 A KR 20150070272A KR 101705588 B1 KR101705588 B1 KR 101705588B1
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KR
South Korea
Prior art keywords
cooling water
flange
inlet
outlet
flange portion
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KR1020150070272A
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Korean (ko)
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KR20160136590A (en
Inventor
김남원
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신일인텍 주식회사
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    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
    • C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
    • C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
    • C21C7/10—Handling in a vacuum

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Treatment Of Steel In Its Molten State (AREA)

Abstract

The present invention improves the cooling structure of the submerged pipe to cool and supply the cooling water without deformation of the flange portion, prevents mixing of the cooling water with the vortex, improves the structure for facilitating the bolt assembly at the flange portion, To a deposit tube structure for a vacuum degassing facility whose structure is improved.
A deposit tube structure for a vacuum degassing apparatus according to the present invention is characterized in that a refractory material is provided inside and outside, a flange portion 110 is extended outward, and a cylindrical body is provided on the lower side in a direction orthogonal to the flange portion 110 An inner skin 100 on which a part 120 is provided; An inlet (210) and an outlet (220) provided outside the flange (110) for the inflow and outflow of cooling water; A cooling water flow path 250 formed along the inner periphery of the flange 110 and connected to circulate the cooling water introduced through the inlet 210 to flow out to the outlet 220; The cooling water channel 250 is installed in a direction perpendicular to the flow of the cooling water in the cooling water channel 250 between the inlet 210 and the outlet 220 so as to prevent swirling of the cooling water in the cooling water channel 250, A diaphragm 255 formed thereon; A plurality of engaging recesses 310 formed to be open to the outside so as to allow the bolt member 510 to enter the circumferential direction on the rim of the flange 110; A pair of guide plates 320a and 320b facing each other at the lower left and right sides of the coupling grooves 310 to prevent the nut member 520 from being loosened, A fixed guide 320 made of a metal material; And a plurality of annular reinforcing ribs 125 formed at different heights h1 and h2 around the lower portion of the body portion 120. [

Description

{IMMERSION VESSEL STRUCTURE OF VACUUM DEGASSING SYSTEM}

The present invention relates to a vacuum tube structure for a vacuum degassing apparatus, and more particularly, to a vacuum tube structure for a vacuum degassing apparatus, which can improve the cooling structure of a submerged pipe to cool and supply cooling water without deformation of a flange portion, To a deposit tube structure for a vacuum degassing facility whose structure is improved so as to facilitate assembly and whose structure is improved so as to improve the reinforcing property of the inner iron.

Generally, the molten steel which is introduced from the converter and contained in the ladle is to be degassed for separating the gas and the inclusion contained in the molten steel in the degassing process. In the degassing process, the upper and lower vacuum vessels , The inside of the downfalling dipper tube is composed of refractory bricks, and the refractory bricks are abraded by the hot molten material.

The degassing equipment for refining the molten steel in the ladle is made by vacuuming the underfloor air conditioning by using the physical phenomenon of the water vapor, sucking the molten steel of the ladle by the upwardly immersed pipe immersed in the molten steel, discharging the molten steel by the down- The main purpose is to degas the exhaust gas duct connected to the upper vacuum tank through the reflux process that forms the molten steel flow.

In order to adjust the composition and temperature of the molten steel contained in the ladle during the degassing process, the raw material is introduced from the feed line connected to the upper vacuum chamber, and oxygen and inert gas And then the molten steel is introduced into the vacuum tank. Through this series of degassing processes, a better quality molten steel product can be produced.

That is, the degassing process in the steelmaking process is the last step for determining the quality of molten steel, and is an important process for fine adjustment of components and fine adjustment of temperature.

The degassing process will be described in more detail. First, the ladle placed on the ladle carrier truck is moved up and down by a ladle lifting cylinder provided on the ladder, As a result, the deposition tube of the lower vacuum chamber is contained in the molten steel filled in the ladle.

In this state, the vacuum pressure in the lower vacuum air conditioning is adjusted so that the molten steel is sucked into the uprising pipe and the molten steel is discharged in the reverse direction to the downrising pipe, so that the molten steel flows into the molten steel flow Degassing treatment was carried out while refluxing.

However, during this degassing process, the molten steel flow passing between the rising and falling deposition pipes, which are the lower part of the lower vacuum chamber, and the outer surface of the deposition pipe directly contacting the slag are locally frayed, The brick was damaged and the service life of the submerged pipe was lowered.

Accordingly, in order to reinforce the damaged refractories during the conventional degassing process, the repair work of spraying the reinforcing material on the outer surface of the submerged pipe has been performed. However, there has been a problem that the work productivity is lowered due to the increase of the working time.

Further, in the case of puncturing the submerged pipe during the degassing process, the vacuum degree is lowered to lower the treatment efficiency of the degassing, thereby causing instability of the molten steel refining operation, while strengthening the inside of the submerged pipe locally There is a limitation in reinforcing the fused drain pipe, which has a problem that the work time for reinforcing is prolonged for a long time.

Therefore, the use of the submerged pipe due to the local wear of the submerged pipe during the degassing process causes the lifetime of the submerged pipe to be lowered, which increases the unit cost of the refractory constituting the submerged pipe, Resulting in a decrease in productivity and an increase in manufacturing cost, which in turn caused a great deal of trouble in various work processes.

As a conventional prior art for solving the above problems, there has been proposed a method in which, as disclosed in Korean Patent Registration No. 10-0825553 entitled " Device for protecting refractory of refractory tube of degassed vacuum tank "(registered on Apr. 21, 2008) The dam block being horizontally movably mounted on a guide bar disposed in a direction transverse between the upward and downward sinking pipes so as to intercept the flow of molten steel between the rising and falling sinking pipes; And an operation part for providing a power source for horizontally moving the dam block between the ascending and descending deposit tubes, wherein the dam block has a connecting hole into which the connecting ring of the hollow guide member, which is assembled horizontally movably to the guide rod, A dam member of a rectangular parallelepiped which is detachably assembled and a refractory surface refractory which is coated on both left and right outer surfaces of the dam member corresponding to the deposit pipe.

Another prior art related to the conventional deposition tube is disclosed in Korean Patent Registration No. 10-0916065 entitled " Submerged Pipe for Inhalation of Slag at the Start of Vacuum "(Registered Date: Aug. 31, 2009) A refractory member provided on the lower side of the connection portion; And diaphragm means connected to the iron pipe connection portion and provided with a refractory brick corresponding to the thickness of the slag on the upper side of the molten steel and provided to block the suction of the vacuum tank of the slag at the start of the vacuum.

However, if the flange structure is modified in order to supply the cooling water to the flange portion of the existing submerged pipe, external air will not be able to be vacuumed, and vortex will be generated in the cooling water flow process. have.

In addition, since the existing submerged pipe is difficult to disassemble and assemble the bolt and nut during disassembly and assembly, it takes a long time to work, and since the bolt must be fastened while fixing the nut in the predetermined position during the assembly of the bolt, If the bolt and nut are loosened, the assembly time is delayed.

Since the conventional deposit tube structure is composed of the inner iron core and the refractory provided on the inner and outer sides of the inner iron core, the inner iron core is easily deformed by heat. Accordingly, a reinforcement structure for preventing the inner iron core from being deformed It is a fact that is demanded.

Korean Patent Registration No. 10-0825553 entitled "Device for protecting refractory material from deposition tube of degassed vacuum tank" (registered on Apr. 21, 2008) Korean Registered Patent No. 10-0916065 "Substrate for slag inhalation at the time of initiation of vacuum" (registered on August 31, 2009)

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and it is an object of the present invention to improve a cooling structure of a submerged pipe, to cool and supply cooling water without deformation of a flange portion, There is provided a deposit tube structure for a vacuum degassing apparatus, the structure of which is improved so as to facilitate bolt assembly at a flange portion and whose structure is improved so as to improve the reinforcing property of the inner iron.

According to an aspect of the present invention, there is provided an internal combustion engine comprising: an internal combustion engine having a refractory material inside and outside, a flange portion extending outwardly from an upper portion thereof, and a cylindrical body portion provided below the flange portion in a direction orthogonal to the flange portion; An inlet and an outlet provided outside the flange for inlet and outlet of cooling water; A cooling water flow path formed along the inner periphery of the flange portion and connected to circulate the cooling water introduced through the inlet port to flow out to the outlet side; A diaphragm installed in a direction perpendicular to the flow of the cooling water in the cooling water flow path between the inlet and the outlet so as to prevent vortex of the cooling water in the cooling water flow path; A plurality of engaging recesses formed on an edge portion of the flange portion so as to open outwardly so that the bolt member can enter the outside in a circumferential direction; A fixing guide formed of a pair of guide plates arranged to face each other at a lower left and right positions of each of the engaging grooves so as to prevent loosening of a nut member to which the bolt member is fastened; And a plurality of annular reinforcing ribs formed at different heights around the lower portion of the body portion.

And a plurality of inlet holes for degassing the molten steel are further provided on the outer circumference of the body portion.

The flange portion may further include a circumferential groove formed in a concave groove shape on an upper surface thereof, and a sealing member inserted and coupled to the circumferential groove.

The present invention relates to a vacuum degassing apparatus which improves the structure of a submerged pipe in which molten steel is refluxed in a vacuum degassing facility so as to provide a cooling water flow path for circulating cooling water in a flange portion of a submerged pipe and a partition plate having a through hole between the cooling water inlet port and the outlet port, It is possible to prevent the vortex from being generated and to prevent the deformation of the internal iron due to the overheating by providing the cooling function to the flange portion. It is also possible to improve the assembling property of the bolt member and the nut member, It has a useful effect of preventing loosening of the member.

In addition, the present invention has an advantage in that deformation due to heat generated during the reflux process of the molten steel can be suppressed by welding the reinforcing rib in the form of a round bar protruding along the outer circumference of the body portion.

1 is a perspective view showing a deposition tube structure for a vacuum degassing apparatus according to the present invention.
2 is a plan view of Fig.
Figure 3 is a plan view of Figure 2;
4 is an enlarged view of the "A"
Fig. 5 is an enlarged view of a portion "B" in Fig. 3; Fig.
6 is a plan view showing an engaging groove portion and a fixing guide according to the present invention.
Fig. 7 is a front view of Fig. 6; Fig.
8A and 8B are a bottom perspective view and a coupled state view showing a state in which a bolt member and a nut member are engaged with each other according to the present invention.

1 to 7, refractory materials are provided on the inside and the outside, respectively, and a flange portion 110 is extended outwardly from the upper portion, and the flange portion And an inlet port 210 and an outlet port 210. The inlet port 210 and the outlet port 210 are provided on the outer side of the flange 110 to allow the cooling water to flow in and out, And a cooling water flow path 250 formed along the inner periphery of the flange 110 and connected to circulate the cooling water introduced through the inlet 210 and flow out to the outlet 220.

1, the inner iron sheet 100 includes a cylindrical body portion 120 having a hollow communicating with the upper portion and the lower portion, a flange portion extending outward in the circumferential direction at an upper end of the body portion 120 110).

The body portion 120 is formed to protrude along the outer circumference and has a plurality of reinforcing ribs 125 formed at different heights h1 and h2, thereby having an advantage of preventing deformation due to heat.

The reinforcing ribs 125 may be integrally fixed to the outer circumference of the body part 120 by welding or the like.

In addition, the body 120 has a plurality of inlet holes 122 formed along the outer circumference thereof for introducing argon gas, which is an inert gas for degassing, into the molten steel therein.

As shown in FIGS. 2 and 3, the flange 110 is integrally formed to extend outward along the upper edge of the body 120. The flange 110 has cooling water circulated along the outer circumference of the flange 110, (Not shown).

The flange 110 has an inlet 210 connected to the outside of the flange 110 through which the cooling water is introduced and an outlet 220 through which the cooling water circulated along the cooling water flow path 250 flows out, Lt; / RTI >

The inlet port 210 is connected to one end of the cooling water flow path 250 and the outlet port 220 is connected to the other end of the cooling water flow path 250.

The cooling water channel 250 has a circular shape as viewed in a plan view along the disk-shaped flange portion 110 and is connected to the inlet 210 and the outlet 220 as shown in FIGS. A diaphragm 255 is provided in a direction orthogonal to the flow of the cooling water to prevent vortexing of the cooling water between the parts.

The diaphragm 255 is formed with a through hole 255a so as not to prevent the flow of the cooling water.

6 and 7, the flange 110 includes a coupling groove portion 310 (see FIG. 6 and FIG. 7) having a shape that is open to the outside so that the bolt member 510 for coupling with the lower portion of the vacuum chamber can easily enter from the outside And a fixing guide 320 is provided at a position spaced apart from the lower side of the coupling groove 310 in order to prevent loosening of the nut member 520 to which the bolt member 510 is fastened, Respectively.

The fixing guide 320 is composed of a pair of guide plates 320a and 320b facing each other on the left and right sides of the lower side of the coupling groove 310 and fixed to the lower side of the coupling groove 310 by welding .

The fixing guide 320 is formed at an interval corresponding to the outer diameter of the nut member 520 so as to prevent rotation of the nut member 520 to which the bolt member 510 is fastened, And functions to prevent the bolt member 510 from being loosened and guide the nut member 520 to the correct position by guiding the bolt member 510 to the correct position do.

The flange portion 110 has a concave groove-shaped circumferential groove 112 and a sealing member 410 fitted to be coupled to the circumferential groove 112 so as to maintain airtightness at the upper side of the vacuum tank when the coupling portion is coupled with the lower portion of the vacuum tank. .

The sealing material 410 may employ an "O" ring for blocking external air from entering the hollow interior.

The present invention having such a construction has an assembling process in which refractory bricks, which are refractories, are attached to the inner and outer sides of the inner iron sheet 100 and are fastened to the lower portion of the vacuum tank by the bolts 510.

After the assembling process is completed, the molten steel in the ladle passes through the upper vacuum chamber through the uprising pipe, and then is circulated back to the ladle through the downfalling dip pipe. Through the reflux process of the molten steel flow, Degassing the exhaust gas duct connected to the vacuum tank.

The cooling water is circulated along the cooling water flow path 250 formed along the periphery of the flange portion 110 when the external cooling water flows into the cooling water flow path 250 through the inlet 210 for cooling the flange portion 110. [ do.

At this time, a diaphragm 255 is formed in the cooling water flow path 250 between the inlet port 210 through which the cooling water flows and the outlet port 220 through which the cooling water flows out to the outside, 255a are formed, it is possible to prevent generation of vortex due to the inflow and outflow of the cooling water.

As a result, the cooling water circulates through the cooling water flow path 250 and then performs a cooling function to cool the flange portion 110 while exchanging heat in the process of flowing out to the outside.

8A, the assembly of the bolt member 510 and the nut member 520 for assembling the vacuum tank is performed by inserting the nut member 520 (see FIG. 8A) into the fixing guide 320 fixed to the lower side of the coupling groove 310 And then the bolt member 510 is inserted into the outwardly opened coupling groove 310 and then the bolt member 510 is fastened to the nut member 520 supported by the fixing guide 320. [

8B, both the inner side surfaces facing each other are in surface contact with the outer periphery of the head of the nut member 520 fastened with the bolt member 510, so that the nut member 520 and the bolt member 520, The fastening operation can be performed at a predetermined position by restraining the nut member 520 to be fastened to the bolt member 510 as described above.

The bolt member 510 of the present invention can be easily inserted into the coupling groove 310 that is open to the outside, so that the bolt member 510 can be easily assembled with the nut member 520, And the efficiency is improved.

At least one or more reinforcing ribs 125 are provided on the lower portion of the body portion 120 to prevent thermal deformation of the body portion 120.

Therefore, the present invention is characterized in that the cooling water passage 250 for circulating the cooling water is provided in the flange portion 110 and the partition plate 255 having the through hole 255a is provided between the cooling water inlet 210 and the outlet 220 It is possible to prevent the cooling water from generating vortex so that the cooling function is given to the flange 110 to prevent the deformation of the inner steel pipe 100 due to the overheating and the bolt member 510 and the nut member 520 can be improved and the nut member 520 can be prevented from being loosened.

Further, the present invention has an advantage in that deformation due to heat generated during the reflux process of the molten steel can be suppressed by welding the reinforcing ribs 125 in the form of a round bar protruding along the outer periphery of the body portion 120.

100: inner scoop 110: flange
112: circumferential groove 120:
122: inlet hole 125: reinforcing rib
210: inlet 220: outlet
250: cooling water channel 255: diaphragm
255a: through hole 310: engagement groove
320: fixed guide 320a, 320b: guide plate
410: Sealing material 510: Bolt member
520: Nut member

Claims (5)

(100) having a refractory material inside and outside thereof, a flange part (110) extending outwardly from the upper part, and a cylindrical body part (120) provided below the flange part (110) in a direction perpendicular to the flange part (110);
An inlet (210) and an outlet (220) provided outside the flange (110) for the inflow and outflow of cooling water;
A cooling water flow path 250 formed along the inner periphery of the flange 110 and connected to circulate the cooling water introduced through the inlet 210 to flow out to the outlet 220;
The cooling water channel 250 is installed in a direction perpendicular to the flow of the cooling water in the cooling water channel 250 between the inlet 210 and the outlet 220 so as to prevent swirling of the cooling water in the cooling water channel 250, A diaphragm 255 formed thereon;
A plurality of engaging recesses 310 formed to be open to the outside so as to allow the bolt member 510 to enter the circumferential direction on the rim of the flange 110;
A pair of guide plates 320a and 320b facing each other at the lower left and right sides of the coupling grooves 310 to prevent the nut member 520 from being loosened, A fixed guide 320 made of a metal material; And
And a plurality of annular reinforcing ribs (125) formed at different heights (h1, h2) around the lower part of the body part (120). The method according to claim 1,
And a plurality of inlet holes (122) for degassing the molten steel are further provided on the outer circumference of the body part (120). delete delete The method according to claim 1,
The flange portion 110 includes a circumferential groove 112 formed in a concave groove shape on the upper side,
And a sealing member (410) fitted to the peripheral groove (112) and coupled with the peripheral groove (112).
KR1020150070272A 2015-05-20 2015-05-20 Immersion vessel structure of vacuum degassing system KR101705588B1 (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20190010268A (en) * 2017-07-21 2019-01-30 주식회사 포스코 Blast furnace apparatus and method for reinforcing the same

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20190057708A (en) * 2017-11-20 2019-05-29 (주)포스코케미칼 Iron plate in deposition tube

Citations (1)

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Publication number Priority date Publication date Assignee Title
JP2000212640A (en) * 1999-01-25 2000-08-02 Kobe Steel Ltd Vacuum degassing apparatus and sealing of its joining part

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Publication number Priority date Publication date Assignee Title
JPH02129314A (en) * 1988-11-08 1990-05-17 Sumitomo Metal Ind Ltd Method for cooling connecting part in vacuum refining vessel
JP2709577B2 (en) * 1995-03-02 1998-02-04 川崎重工業株式会社 Vacuum degassing device and attachment / detachment device for immersion tube
JPH1088221A (en) * 1996-09-06 1998-04-07 Nkk Corp Probe for observing inner part of metallurgical furnace and method for observing inner part of metallurgical furnace
KR100825553B1 (en) 2001-10-26 2008-04-25 주식회사 포스코 An apparatus for protecting the brick of vessel in degassing vacuum
KR100916065B1 (en) 2002-12-21 2009-09-08 주식회사 포스코 A submerged pipe for rh systen

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2000212640A (en) * 1999-01-25 2000-08-02 Kobe Steel Ltd Vacuum degassing apparatus and sealing of its joining part

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20190010268A (en) * 2017-07-21 2019-01-30 주식회사 포스코 Blast furnace apparatus and method for reinforcing the same
KR101998744B1 (en) * 2017-07-21 2019-07-10 주식회사 포스코 Blast furnace apparatus and method for reinforcing the same

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