WO2021106120A1 - Dip tube for molten steel processing - Google Patents

Dip tube for molten steel processing Download PDF

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Publication number
WO2021106120A1
WO2021106120A1 PCT/JP2019/046462 JP2019046462W WO2021106120A1 WO 2021106120 A1 WO2021106120 A1 WO 2021106120A1 JP 2019046462 W JP2019046462 W JP 2019046462W WO 2021106120 A1 WO2021106120 A1 WO 2021106120A1
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WIPO (PCT)
Prior art keywords
brick
refractory
core metal
upper support
support
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PCT/JP2019/046462
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French (fr)
Japanese (ja)
Inventor
庄吾 寺田
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東京窯業株式会社
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Priority to PCT/JP2019/046462 priority Critical patent/WO2021106120A1/en
Publication of WO2021106120A1 publication Critical patent/WO2021106120A1/en

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    • CCHEMISTRY; METALLURGY
    • C21METALLURGY OF IRON
    • C21CPROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
    • C21C7/00Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
    • C21C7/10Handling in a vacuum

Definitions

  • the present invention relates to an immersion pipe for molten steel processing used in a vacuum degassing device or the like.
  • a dipping pipe that distributes molten steel with the lower end immersed in the molten steel in the ladle is attached to the lower end of the vacuum degassing device and used.
  • a dipping tube as in Patent Document 1, a cylindrical core metal along a vertical axis and a meat formed by assembling a plurality of rectangular parallelepiped bricks inside the core metal in multiple stages.
  • a thick cylindrical amorphous fireproof material formed on the outer circumference of the core metal by solidifying a thick cylindrical brick layer (inner fireproof material layer) and a fluid amorphous fireproof material (castable, etc.). Those with layers are known.
  • a magnesia-carbon material is placed on the outside of the core metal.
  • Some are assembled with multiple vertically long refractory bricks.
  • a situation may occur in which the outer refractory brick is disengaged due to an outward thermal expansion stress during use. .. Therefore, some immersion pipes in which refractory bricks are assembled on the outside of the core metal are provided with locking metal fittings for locking the upper and lower ends of the outer refractory bricks (Patent Document 2).
  • Patent Document 2 in the immersion pipe in which the locking metal fitting for locking the upper end of the outer refractory brick is provided at an angle with respect to the core metal, the locking metal fitting is a splash scattered during use. It is very vulnerable to damage due to being exposed to (splashes of molten steel), being strongly affected by radiant heat, and being impacted during slag removal work (so-called slag removal). Therefore, the immersion pipe as in Patent Document 2 has a problem that the service life is short and maintenance is required frequently, so that the maintenance cost is high.
  • the immersion pipe of the type with a flange on the core metal is installed so that the molten metal surface is located near the center so that the scattered splash does not adhere to the flange, and the molten steel treatment is performed, but the core metal does not have a flange. Since there is no concern about the influence of the splash on the flange of the type (flangeless type) immersion pipe, the molten steel treatment is performed by immersing it in the molten metal deeper (immersing it until the molten metal surface is near the upper part). However, when immersed in the molten metal so deeply, the locking metal fitting for locking the upper end of the outer refractory brick is more easily damaged by the influence of splash and heat.
  • An object of the present invention is to solve the problems of the conventional immersion pipe, the locking metal fittings for locking the outer refractory bricks are not easily damaged, the service life is long, and frequent maintenance is not required. It is an object of the present invention to provide an immersion tube which can keep the maintenance cost low.
  • the invention according to claim 1 is a dipping tube for processing molten steel used as an ascending tube or a descending tube in a molten steel vacuum degassing device, which is a cylindrical iron core metal.
  • An inner refractory layer provided inside the core, a plurality of outer refractory bricks arranged in a circumferential shape on the outside of the core, and the outer refractory brick provided near the lower end of the core.
  • the upper side of the brick upper support is covered with an amorphous refractory
  • the tip of the brick upper support is covered with the outer fire resistance. It is characterized in that locking pieces for locking the side surfaces of the brick are continuously provided vertically downward, and the outer portion of the locking pieces is covered with an amorphous refractory material.
  • cement castable, low cement castable, other castables and the like can be preferably used as the amorphous refractory in the present invention.
  • the invention according to claim 2 is characterized in that, in the invention according to claim 1, a stud for preventing the amorphous refractory from falling off is provided on the upper surface of the brick upper support. It is to be.
  • the invention according to claim 3 is the invention according to claim 1 or 2, wherein the core metal is a flangeless type.
  • the brick upper support is scattered (splash). It is not exposed to the droplets of molten steel) and is not easily affected by radiant heat, etc., and the impact is not easily transmitted to the upper support during the slag removal work, so the installation part of the upper support is less likely to be damaged. Therefore, according to the immersion pipe according to claim 1, the service life can be extended and frequent maintenance is not required, so that the maintenance cost can be kept low.
  • the immersion pipe according to claim 1 is provided with an annular shape in which the upper brick support is inclined downward, thermal expansion stress that tends to diffuse in the radial direction to the outer refractory brick during use is applied. Even if it is added, the thermal expansion stress can be effectively suppressed and the outer refractory brick can be prevented from falling off.
  • the locking piece since the outer portion of the locking piece connected vertically downward to the tip of the brick upper support is covered with an amorphous refractory, the locking piece is used. Since it is not exposed to scattered splashes and is not easily affected by radiant heat or the like, the locking piece can continue to lock the side surface of the outer refractory brick. Therefore, according to the immersion pipe according to claim 3, it is possible to effectively prevent the outer refractory brick from falling off for a long period of time.
  • the amorphous refractory covering the upper side of the brick upper support is hard to fall off, so that it lasts for an extremely long period of time. It is possible to prevent damage to the installation part of the brick upper support with high accuracy.
  • the molten steel treatment can be performed in a stable state by immersing it in the molten metal deeper without damaging the locking metal fitting for locking the upper end of the outer refractory brick. It will be possible.
  • the immersion tube 1 is a so-called flangeless type in which no flange is provided on the outer periphery of the upper end, and the core metal 3, the inner refractory layer 2, the fall restraint body 10 supporting the lower ends of the inner refractory layer 2, and the core metal Inner amorphous refractory 4, metal pipe 5, outer refractory bricks 6, 6 ... forming the outer refractory layer, inner refractory layer 2 and outer, filled in the voids between 3 and the inner refractory layer 2.
  • Lower refractory 7 formed under the refractory bricks 6, 6 ..., the upper refractory support 8 that supports the upper end of the outer refractory bricks 6, 6 ..., and the lower end of the outer refractory bricks 6, 6 ... It is composed of a brick lower support 11, a horizontal reinforcing body 9 that supports the brick upper support 8, an upper refractory 15 that covers the brick upper support 8, and the like.
  • the core metal 3 is formed of a metal (steel) plate having a certain thickness (25 mm) into a cylindrical shape having a predetermined size (inner diameter 770 mm ⁇ height 800 mm).
  • the upper end surface of the core metal 3 has a tapered shape that is inclined downward.
  • a fall prevention body 10 for supporting the inner refractory layer 2 is provided in an annular shape (doughnut plate shape) having a constant width (at the lower end of the core metal 3). (Welded inside).
  • annular brick lower support 11 for supporting the outer refractory bricks 6, 6, ... Is provided.
  • the brick lower support 11 is formed in an annular shape (doughnut plate shape) having a constant width that matches the lower ends of the outer refractory bricks 6, 6, ..., And is welded to the outside near the lower end of the core metal 3.
  • the upper surface of the brick lower support 11 is located below the upper surface of the fall restraint body 10.
  • studs 12, 12, ... Formed in a V shape by steel (stainless steel) are formed on the lower end surface of the cylindrical main body of the core metal 3, the lower surface of the fall restraint body 10 and the brick lower support 11, respectively. It is attached.
  • the inner refractory layer 2 is formed by the upper refractory bricks 2a, 2a ... and the lower refractory bricks 2b, 2b ...
  • the lower refractory bricks 2b, 2b ... Are formed of a magnesia-chromic material into a vertically long square columnar having a trapezoidal horizontal cross section.
  • a cylindrical body having a predetermined thickness (outer diameter 700 mm x inner diameter 400 mm) is formed. There is.
  • the columnar body made of the upper refractory bricks 2a, 2a ... is laminated on the columnar body made of the lower refractory bricks 2b, 2b ...
  • through holes 13, 13 ... are provided alternately at predetermined intervals (every other along the circumference). It is in a state of communicating with the tip of the metal pipe 5.
  • the inner irregular shape is formed so as to fill the gap between the outer peripheral surface of the inner refractory layer 2 (that is, the upper refractory bricks 2a, 2a ... and the lower refractory bricks 2b, 2b ...) and the inner peripheral surface of the core metal 3. It is filled with refractory material (castable) 4.
  • each of the outer refractory bricks 6, 6 ... Is formed of a magnesia carbon material into a vertically long square columnar having a trapezoidal horizontal cross section.
  • An outwardly descending inclined surface is provided on the upper side of each of the outer refractory bricks 6, 6, ...,
  • an outwardly ascending inclined surface is provided on the lower side.
  • the upper inclined surface and the lower inclined surface are in a state of forming an angle of 45 ° with respect to the horizontal plane.
  • each of the outer refractory bricks 6, 6 ... Is assembled in a circumferential shape on the outside of the core metal 3 to form a cylindrical body having a predetermined thickness (outer diameter 1000 mm x inner diameter 850 mm). It has become. Further, an amorphous refractory (alumina-magnesia type) is provided so as to fill the gap between the inner surface of the outer refractory bricks 6, 6 ... It is in a filled state.
  • amorphous refractory alumina-magnesia type
  • the horizontal reinforcing body 9 is formed in an annular shape (doughnut plate shape) having a constant width and a constant thickness, and is horizontally fixed (welded) to the outside near the upper end of the core metal 3.
  • the brick upper support 8 is formed in an annular shape (outer peripheral surface of a truncated cone) in which the inclined support portion 16 is inclined outward with a constant width and a constant thickness, and is outside the inclined support portion 16. Locking pieces 17 having a constant width are continuously provided on the peripheral edge so as to project vertically downward.
  • the inclined support portion 16 is in a state of being inclined by 45 ° with respect to the horizontal plane.
  • the brick upper support 8 is fixed to the horizontal reinforcing body 9 in a state where the inner peripheral edge portion of the base end is welded to the lower surface near the base end (inner peripheral edge) of the horizontal reinforcing body 9.
  • columnar reinforcing supports 18, 18 ... Having a predetermined diameter are arranged at equal intervals (cores) in a circumferential shape so as to connect the upper surface of the brick upper support 8 and the lower surface of the horizontal reinforcing body 9. It is provided at equal angles to the center of the gold 3.
  • studs 14, 14 ... To prevent the upper refractory 15 from falling off are provided on the upper surface of the horizontal reinforcing body 9 and the upper surface of the inclined support portion 16 of the brick upper support 8, respectively. .. Then, as described above, the brick upper support 8 integrated with the horizontal reinforcing body 9 presses the upper surface of the outer refractory bricks 6, 6 ... On the lower surface of the inclined support portion 16, and the locking piece 17 is used on the outer side. The outer surfaces of the refractory bricks 6, 6 ... are locked.
  • an upper refractory 15 made of an amorphous refractory (alumina-based castable) is formed so as to cover the upper side of the brick upper support 8 and wrap the horizontal reinforcing body 9, and the outer peripheral surface becomes cylindrical.
  • FIG. 4 is an enlarged view of the installation portion of the brick upper support 8, and the amorphous refractory constituting the upper refractory 15 is locked at the tip (lower end) of the brick upper support 8.
  • the outer surface and the lower end surface of the piece 17 are also covered.
  • the amorphous refractory located outside the locking piece 17 and the amorphous refractory located below the lower end surface of the locking piece 17 both have a thickness of about 5 mm.
  • metal pipes 5, 5, ... For discharging lift gas (argon gas) are provided at the upper end of the core metal 3.
  • These metal pipes 5, 5, ... Consists of a discharge portion bent in a substantially L shape and a relay portion extended in the vertical direction.
  • the upper portion of the discharge portion is in a state of vertically projecting upward from the amorphous refractory material 15, and the lower portion of the discharge portion penetrates the core metal and is connected to the upper end of the relay portion. It is in the state of being.
  • the lower end of the relay portion is in a state of communicating with the through holes 13, 13 ... drilled in the lower refractory bricks 2b, 2b ...
  • a thick cylindrical lower refractory 7 made of an amorphous refractory (alumina-magnesia castable) is formed at the lower end of the core metal 3, and the inner and outer circumferences of the lower end of the core metal 3 are formed.
  • the lower surface of the inner refractory layer 2, the lower surface of the fall restraint body 10, the lower surface of the brick lower support 11, and the lower inclined surface of the outer refractory bricks 6, 6, ... Are integrally covered.
  • the inner peripheral surface of the lower refractory 7 is flush with the inner peripheral surface of the inner refractory layer 2, and the outer peripheral surface of the lower refractory 7 is the outer peripheral surface of the outer refractory bricks 6, 6, ... It is flush with each other.
  • the amorphous refractory material that fills the gap between the inner surface of the outer refractory bricks 6, 6 ... And the outer peripheral surface of the core metal 3 and the amorphous refractory material that constitutes the lower refractory material 7 are integrated.
  • FIG. 5 shows an example of how to use the immersion tube 1 configured as described above.
  • a pair of dipping pipes 1 are connected to a recirculation pipe C fixed at the lower end of the vacuum degassing device M, and the portion near the lower end is immersed in the molten metal (melted iron) S in the pan 24. It is used in the state where it is made.
  • One of the two immersion tubes 1 and 1 so installed (the immersion tube 1a on the left side of FIG. 5) functions as an ascending tube, and the other (the immersion tube 1b on the right side of FIG. 5) descends. Functions as a tube.
  • the upper tank 22 and the lower tank 23 of the vacuum degassing device M are put into a vacuum state, and an inert gas (argon gas or the like) is blown into the immersion pipe 1a which is an ascending pipe via the pipe.
  • an inert gas argon gas or the like
  • the molten metal in the intake pot 24 is drawn into the lower tank 23 side and rises the molten metal passage (inside the inner refractory layer 2) R of the immersion pipe 1a which is an ascending pipe, and then the immersion pipe 1b which is a descending pipe. It descends the molten metal passage R of the above and returns to the pan 24 to recirculate. In the process of such recirculation, the molten metal is degassed.
  • the heat load constitutes the upper refractory material 15. Since it is absorbed by the irregular refractory (alumina-based castable), deformation and melting of the brick upper support 8 are prevented with high accuracy.
  • the immersion tube 1 includes an iron core metal 3 formed in a cylindrical shape and an inner refractory layer 2 (that is, upper refractory bricks 2a, 2a ... And lower stage) provided inside the core metal 3. (2b, 2b 7), a plurality of outer refractory bricks 6, 6 ... arranged in a circumferential shape on the outside of the core metal 3, and to support the lower end edge of the outer refractory bricks 6, 6 ...
  • a brick lower support 11 and a brick upper support 8 for supporting the upper ends of the outer refractory bricks 6, 6 ... are provided, and the upper side of the brick upper support 8 is an amorphous refractory (alumina). System castable) 15 covered.
  • the brick upper support 8 is not exposed to scattered splashes (splashes of molten steel) and is not easily affected by radiant heat or the like, and the impact is applied to the upper part of the brick during the slag removal work. Since it is difficult to transmit to the support 8, the installation portion of the brick upper support 8 is not easily damaged. Therefore, according to the immersion tube 1, the service life can be extended and frequent maintenance is not required, so that the maintenance cost can be kept low.
  • the immersion tube 1 is provided with the brick upper support 8 in an annular shape inclined outward, the thermal expansion stress that tends to diffuse in the radial direction to the outer refractory bricks 6, 6 ... Even when the above is added, the thermal expansion stress can be effectively suppressed and the outer refractory bricks 6, 6 ... Can be prevented from falling off.
  • a locking piece 17 for locking the side surfaces of the outer refractory bricks 6, 6 ... Is connected vertically downward to the tip of the brick upper support 8 and the locking thereof. Since the outer part of the piece 17 is covered with an amorphous refractory (alumina-based castable) 15, the locking piece 17 is not exposed to scattered splashes during use and is not easily affected by radiant heat. The piece 17 can continue to lock the sides of the outer refractory bricks 6, 6, ... Therefore, according to the immersion pipe 1, it is possible to effectively prevent the outer refractory bricks 6, 6, ... From falling off over a long period of time.
  • the immersion pipe 1 has studs 14a, 14a ... Protruding on the upper surface of the brick upper support 8 to prevent the amorphous refractory 15 from falling off, the upper side of the brick upper support 8 is provided. Since the amorphous refractory 15 that covers the brick is hard to fall off, it is possible to prevent damage to the installation portion of the brick upper support 8 with high accuracy for an extremely long period of time.
  • the immersion pipe according to the present invention is not limited to the embodiment described above, and includes a core metal, a brick upper support, a brick lower support, a horizontal reinforcing body, an inner refractory layer, an outer refractory brick, and the like.
  • the composition of the material, shape, structure, size, etc. can be appropriately changed as necessary without departing from the spirit of the present invention.
  • the amorphous refractory covering the upper side of the brick upper support (that is, the amorphous refractory constituting the upper refractory) is an alumina-based castable. It is also possible to change the amorphous refractory covering the upper side of the brick upper support to a material other than the alumina-based castable such as the alumina-magnesia-based castable.
  • the amorphous refractory covering the upper side of the brick upper support is made of a high-strength material such as an alumina-based castable as in the above embodiment, the brick upper support is prevented from being deformed and melted with higher accuracy. There is a merit that it becomes possible to do.
  • the immersion pipe according to the present invention is not limited to the amorphous refractory constituting the lower refractory being an alumina-magnesia castable as in the above embodiment, and the amorphous refractory constituting the lower refractory. Can be changed to another material such as alumina-based castable.
  • the amorphous refractory constituting the lower refractory is made of a material having high spalling resistance such as an alumina-magnesia castable as in the above embodiment, the deformation of the lower part of the core metal is performed with higher accuracy. There is an advantage that it can be prevented.
  • the immersion pipe according to the present invention is not limited to the one in which the inner refractory layer is made of magnesia-chromium material as in the above embodiment, and the inner refractory layer is made of magnesia-carbon material depending on the operating conditions and the like. It is also possible to change to a material other than magnesia-chromic material such as wood.
  • the immersion pipe according to the present invention is not limited to the one in which the brick upper support has the inclined support portion fixed to the horizontal reinforcing body (welded) as in the above embodiment, and the inclined support portion is the core. It is also possible to change to something that is directly fixed to gold.
  • the inclined support portion of the brick upper support is fixed to the horizontal reinforcing body as in the above embodiment, the amorphous refractory constituting the upper reinforcing body is more effectively prevented from falling off.
  • the horizontal reinforcing body effectively blocks the heat transferred from the upper part of the immersion tube, it is possible to prevent deformation and melting of the inclined support portion with higher accuracy.
  • the reinforcing support is a vertical rod-shaped body (cylindrical body) as in the above embodiment. It is not limited to the above, but is integrally formed in a cylindrical shape (flat cylindrical shape) having a constant thickness, or at predetermined intervals (equal intervals or non-equal intervals) along the circumferential upper surface of the brick upper support. It may be a plate such as a plurality of triangular shapes (triangular shapes that gradually widen outward) or trapezoidal shapes (trapezoidal shapes that gradually widen outward) that are installed (welded) in.
  • the immersion pipe according to the present invention is covered with an amorphous refractory on the outside and / or the lower side of the locking piece of the brick upper support as in the above embodiment, the locking piece
  • the thickness of the amorphous refractory covering the outside and / or the underside can be changed as needed, and when the thickness is adjusted to the range of 5 to 15 mm, an unnecessarily large amount of amorphous refractory It is possible to effectively prevent deformation and melting of the locking piece without using an object.
  • a stud obtained by bending a metal rod-shaped body into a V shape is used as a core metal, a brick upper support, a brick lower support, a fall prevention body, or the like.
  • the shape of the stud is not limited to the protruding one, and it is possible to change the shape of the stud to a plate-shaped folded back, a Y-shaped bent, or the like.
  • a single or a plurality of annular bodies made of metal in a band shape or a rod shape are wound around the outer periphery of the lower end edge. It is also possible to change it to something else.
  • the inclined support portion of the brick upper support has an angle of 45 ° with respect to the horizontal plane (that is, the inclined surface on the upper side of each outer fireproof brick is formed.
  • the inclination angle of the inclined support portion of the brick upper support is approximately 0. It can be changed as needed within the range of ⁇ 60 °.
  • the immersion pipe according to the present invention is not limited to the one in which the outer peripheral surface of the lower refractory and the outer peripheral surface of the outer refractory brick are flush with each other as in the above embodiment, and the lower refractory and the outer refractory are not limited to the same. It is also possible to change the lower side (lower part) of the outer refractory brick to one covered with a lower refractory material for the purpose of preventing molten steel from infiltrating from the boundary of the brick.
  • the immersion pipe according to the present invention exerts an excellent effect as described above, it is suitable as a member or the like which is attached to a vacuum degassing device to function as an ascending pipe or a descending pipe when secondary refining molten steel. Can be used.

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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

[Problem] To provide a dip tube with which a metal fitting for locking an outer refractory brick is not susceptible to being damaged, service life is long, frequent maintenance is unnecessary, and maintenance costs can be kept low. [Solution] This dip tube 1 comprises: an iron core metal 3 formed in a cylindrical shape; an inner refractory layer 2 provided on the inner side of the core metal 3; a plurality of outer refractory bricks 6, 6 ... disposed in a circumferential shape on the outer side of the core metal 3; a brick lower support body 11 for supporting the lower end edges of the outer refractory bricks 6, 6 ...; and a brick upper support body 8 for supporting the upper end edges of the outer refractory bricks 6, 6 .... The upper side of the brick upper support body 8 is covered by an unshaped refractory 15.

Description

溶鋼処理用の浸漬管Immersion tube for molten steel processing
 本発明は、真空脱ガス装置等に用いられる溶鋼処理用の浸漬管に関するものである。 The present invention relates to an immersion pipe for molten steel processing used in a vacuum degassing device or the like.
 製鋼の二次精錬の工程においては、取鍋内の溶鋼に下端を浸漬させた状態で溶鋼を流通させる浸漬管が、真空脱ガス装置の下端に装着されて使用される。そして、そのような浸漬管としては、特許文献1の如く、鉛直軸に沿った円筒状の芯金と、その芯金の内側に複数の直方体状のレンガを多段に組み付けることによって形成された肉厚な円筒状のレンガ層(内側耐火物層)と、流動性を有する不定形耐火物(キャスタブル等)を固化させることによって芯金の外周に形成された肉厚な円筒状の不定形耐火物層とを備えたものが知られている。 In the process of secondary refining of steelmaking, a dipping pipe that distributes molten steel with the lower end immersed in the molten steel in the ladle is attached to the lower end of the vacuum degassing device and used. As such a dipping tube, as in Patent Document 1, a cylindrical core metal along a vertical axis and a meat formed by assembling a plurality of rectangular parallelepiped bricks inside the core metal in multiple stages. A thick cylindrical amorphous fireproof material formed on the outer circumference of the core metal by solidifying a thick cylindrical brick layer (inner fireproof material layer) and a fluid amorphous fireproof material (castable, etc.). Those with layers are known.
 また、浸漬管の中には、芯金の外周の不定形耐火物が地金付着や溶損によって変形・脱落してしまう事態を防止するために、芯金の外側に、マグネシア-カーボン質材からなる縦長な複数の耐火レンガを組み付けたものもある。ところが、そのような芯金の外側にマグネシア-カーボン質材からなる耐火レンガを組み付けた浸漬管においては、使用時に、外向きの熱膨張応力が加わって外側耐火レンガが外れてしまう事態が起こり得る。そのため、芯金の外側に耐火レンガを組み付けた浸漬管の中には、それらの外側耐火レンガの上端および下端を係止するための係止金具を設けたものもある(特許文献2)。 In addition, in order to prevent the irregular refractory on the outer circumference of the core metal from being deformed or dropped due to adhesion or melting damage of the core metal, a magnesia-carbon material is placed on the outside of the core metal. Some are assembled with multiple vertically long refractory bricks. However, in a dipping pipe in which a refractory brick made of magnesia-carbon material is assembled on the outside of such a core metal, a situation may occur in which the outer refractory brick is disengaged due to an outward thermal expansion stress during use. .. Therefore, some immersion pipes in which refractory bricks are assembled on the outside of the core metal are provided with locking metal fittings for locking the upper and lower ends of the outer refractory bricks (Patent Document 2).
特開平10-259415号公報Japanese Unexamined Patent Publication No. 10-259415 特開平7-34119号公報Japanese Unexamined Patent Publication No. 7-34119
 しかしながら、上記特許文献2の如き、外側耐火レンガの上端を係止するための係止金具を芯金に対して傾斜状に設けた浸漬管は、その係止金具が、使用時に、飛散したスプラッシュ(溶鋼の飛沫)を浴びたり、輻射熱等の影響を強く受けたり、スラグの除去作業(所謂、ノロ取り)の際の衝撃を受けたりすることによって非常に損傷し易い。それゆえ、上記特許文献2の如き浸漬管は、耐用寿命が短く、頻繁にメンテナンスをすることが必要であるため、維持コストが高い、という不具合がある。また、芯金にフランジがあるタイプの浸漬管は、飛散したスプラッシュがフランジに付着しないように湯面が中央付近に位置するように設置されて溶鋼処理が行われるが、芯金にフランジがないタイプ(フランジレスタイプ)の浸漬管は、フランジへのスプラッシュの影響の心配がないため、より深く溶湯内に浸漬させて(湯面が上部近くになるまで浸漬させて)溶鋼処理が行われる。ところが、そのように深く溶湯内に浸漬させると、外側耐火レンガの上端を係止するための係止金具が、一層スプラッシュや熱の影響を受けて損傷し易くなってしまう。 However, as in Patent Document 2, in the immersion pipe in which the locking metal fitting for locking the upper end of the outer refractory brick is provided at an angle with respect to the core metal, the locking metal fitting is a splash scattered during use. It is very vulnerable to damage due to being exposed to (splashes of molten steel), being strongly affected by radiant heat, and being impacted during slag removal work (so-called slag removal). Therefore, the immersion pipe as in Patent Document 2 has a problem that the service life is short and maintenance is required frequently, so that the maintenance cost is high. In addition, the immersion pipe of the type with a flange on the core metal is installed so that the molten metal surface is located near the center so that the scattered splash does not adhere to the flange, and the molten steel treatment is performed, but the core metal does not have a flange. Since there is no concern about the influence of the splash on the flange of the type (flangeless type) immersion pipe, the molten steel treatment is performed by immersing it in the molten metal deeper (immersing it until the molten metal surface is near the upper part). However, when immersed in the molten metal so deeply, the locking metal fitting for locking the upper end of the outer refractory brick is more easily damaged by the influence of splash and heat.
 本発明の目的は、上記従来の浸漬管が有する問題点を解消し、外側耐火レンガを係止するための係止金具が損傷しにくく、耐用寿命が長い上、頻繁なメンテナンスが不要であり、維持費用を低く抑えることが可能な浸漬管を提供することにある。 An object of the present invention is to solve the problems of the conventional immersion pipe, the locking metal fittings for locking the outer refractory bricks are not easily damaged, the service life is long, and frequent maintenance is not required. It is an object of the present invention to provide an immersion tube which can keep the maintenance cost low.
 本発明の内、請求項1に記載された発明は、溶鋼真空脱ガス装置に上昇管あるいは下降管として用いられる溶鋼処理用の浸漬管であって、円筒状に形成された鉄製の芯金と、その芯金の内側に設けられた内側耐火物層と、前記芯金の外側に円周状に配置された複数の外側耐火レンガと、前記芯金の下端際に設けられた前記外側耐火レンガの下端際を支えるためのレンガ下部支持体と、前記芯金の上端際に設けられた前記外側耐火レンガの上端際を支えるためのレンガ上部支持体とを備えているとともに、前記レンガ上部支持体が、外下がりに傾斜した円環状に設けられたものであり、そのレンガ上部支持体の上側が、不定形耐火物によって覆われており、かつ、前記レンガ上部支持体の先端に、前記外側耐火レンガの側面を係止するための係止片が鉛直下向きに連設されているとともに、その係止片の外側の部分が不定形耐火物によって覆われていることを特徴とするものである。また、本発明における不定形耐火物としては、セメントキャスタブル、低セメントキャスタブル、その他のキャスタブル等を好適に用いることができる。 Among the present inventions, the invention according to claim 1 is a dipping tube for processing molten steel used as an ascending tube or a descending tube in a molten steel vacuum degassing device, which is a cylindrical iron core metal. , An inner refractory layer provided inside the core, a plurality of outer refractory bricks arranged in a circumferential shape on the outside of the core, and the outer refractory brick provided near the lower end of the core. A brick lower support for supporting the lower end of the brick and a brick upper support for supporting the upper end of the outer refractory brick provided at the upper end of the core metal, and the brick upper support However, the upper side of the brick upper support is covered with an amorphous refractory, and the tip of the brick upper support is covered with the outer fire resistance. It is characterized in that locking pieces for locking the side surfaces of the brick are continuously provided vertically downward, and the outer portion of the locking pieces is covered with an amorphous refractory material. Further, as the amorphous refractory in the present invention, cement castable, low cement castable, other castables and the like can be preferably used.
 請求項2に記載された発明は、請求項1に記載された発明において、前記レンガ上部支持体の上面に、不定形耐火物の脱落を防止するためのスタッドが突設されていることを特徴とするものである。 The invention according to claim 2 is characterized in that, in the invention according to claim 1, a stud for preventing the amorphous refractory from falling off is provided on the upper surface of the brick upper support. It is to be.
 請求項3に記載された発明は、請求項1、または2に記載された発明において、前記芯金が、フランジレスタイプのものであることを特徴とするものである。 The invention according to claim 3 is the invention according to claim 1 or 2, wherein the core metal is a flangeless type.
 請求項1に記載の浸漬管は、芯金の外側に配置された外側耐火レンガを支えるレンガ上部支持体の上面が不定形耐火物によって覆われているため、レンガ上部支持体が飛散したスプラッシュ(溶鋼の飛沫)を浴びたりせず、輻射熱等の影響を受けにくい上、スラグの除去作業の際に、その衝撃が上部支持体に伝わりにくいので、上部支持体の設置部分が損傷しにくい。したがって、請求項1に記載の浸漬管によれば、耐用寿命を長くすることができる上、頻繁なメンテナンスが不要となるので、維持費用を低く抑えることができる。 In the immersion pipe according to claim 1, since the upper surface of the brick upper support that supports the outer refractory bricks arranged outside the core metal is covered with an amorphous refractory, the brick upper support is scattered (splash). It is not exposed to the droplets of molten steel) and is not easily affected by radiant heat, etc., and the impact is not easily transmitted to the upper support during the slag removal work, so the installation part of the upper support is less likely to be damaged. Therefore, according to the immersion pipe according to claim 1, the service life can be extended and frequent maintenance is not required, so that the maintenance cost can be kept low.
 また、請求項1に記載の浸漬管は、レンガ上部支持体が外下がりに傾斜した円環状に設けられたものであるため、使用時に外側耐火レンガに放射方向に拡散しようとする熱膨張応力が加わった場合でも、その熱膨張応力を効果的に抑えて、外側耐火レンガの脱落を防止することができる。 Further, since the immersion pipe according to claim 1 is provided with an annular shape in which the upper brick support is inclined downward, thermal expansion stress that tends to diffuse in the radial direction to the outer refractory brick during use is applied. Even if it is added, the thermal expansion stress can be effectively suppressed and the outer refractory brick can be prevented from falling off.
 さらに、請求項1に記載の浸漬管は、 レンガ上部支持体の先端に鉛直下向きに連設された係止片の外側の部分が不定形耐火物によって覆われているため、使用時に係止片が飛散したスプラッシュを浴びたりしない上、輻射熱等の影響を受けにくいので、係止片が外側耐火レンガの側面を係止し続けることができる。したがって、請求項3に記載の浸漬管によれば、外側耐火レンガの脱落を長期間に亘って効果的に防止することができる。 Further, in the immersion pipe according to claim 1, since the outer portion of the locking piece connected vertically downward to the tip of the brick upper support is covered with an amorphous refractory, the locking piece is used. Since it is not exposed to scattered splashes and is not easily affected by radiant heat or the like, the locking piece can continue to lock the side surface of the outer refractory brick. Therefore, according to the immersion pipe according to claim 3, it is possible to effectively prevent the outer refractory brick from falling off for a long period of time.
 請求項2に記載の浸漬管は、レンガ上部支持体の上面にスタッドが突設されているため、レンガ上部支持体の上側を覆った不定形耐火物が脱落しにくいので、きわめて長期間に亘って高い精度でレンガ上部支持体の設置部分の損傷を防止することができる。 In the immersion pipe according to claim 2, since the studs are projected on the upper surface of the brick upper support, the amorphous refractory covering the upper side of the brick upper support is hard to fall off, so that it lasts for an extremely long period of time. It is possible to prevent damage to the installation part of the brick upper support with high accuracy.
 請求項3に記載の浸漬管によれば、外側耐火レンガの上端を係止するための係止金具を損傷させることなく、より深く溶湯内に浸漬させて安定した状態で溶鋼処理を行うことが可能となる。 According to the dipping pipe according to claim 3, the molten steel treatment can be performed in a stable state by immersing it in the molten metal deeper without damaging the locking metal fitting for locking the upper end of the outer refractory brick. It will be possible.
浸漬管を示す説明図(鉛直断面図)である。It is explanatory drawing (vertical sectional view) which shows the immersion tube. レンガ上部支持体の設置部分を拡大して示す説明図(鉛直断面図)である。It is explanatory drawing (vertical sectional view) which shows the installation part of the brick upper support enlarged. 浸漬管の使用状態を示す説明図(鉛直断面図)である。It is explanatory drawing (vertical sectional view) which shows the use state of the immersion pipe.
 以下、本発明に係る浸漬管の一実施形態について、図面に基づいて詳細に説明する。
<浸漬管の構造>
 図1、図2は、本発明に係る浸漬管の一例を示したものである。浸漬管1は、上端の外周にフランジを設けない、所謂、フランジレスタイプのものであり、芯金3、内側耐火物層2、内側耐火物層2の下端を支える落下抑止体10、芯金3と内側耐火物層2との空隙に充填された内側不定形耐火物4、金属パイプ5、外側耐火物層を形成している外側耐火レンガ6,6・・、内側耐火物層2および外側耐火レンガ6,6・・の下側に形成された下部耐火物7、外側耐火レンガ6,6・・の上端際を支えるレンガ上部支持体8、外側耐火レンガ6,6・・の下端を支えるレンガ下部支持体11、レンガ上部支持体8を支える水平補強体9、レンガ上部支持体8を覆う上部耐火物15等によって構成されている。
Hereinafter, an embodiment of the immersion tube according to the present invention will be described in detail with reference to the drawings.
<Structure of immersion tube>
1 and 2 show an example of the immersion tube according to the present invention. The immersion tube 1 is a so-called flangeless type in which no flange is provided on the outer periphery of the upper end, and the core metal 3, the inner refractory layer 2, the fall restraint body 10 supporting the lower ends of the inner refractory layer 2, and the core metal Inner amorphous refractory 4, metal pipe 5, outer refractory bricks 6, 6 ... forming the outer refractory layer, inner refractory layer 2 and outer, filled in the voids between 3 and the inner refractory layer 2. Lower refractory 7 formed under the refractory bricks 6, 6 ..., the upper refractory support 8 that supports the upper end of the outer refractory bricks 6, 6 ..., and the lower end of the outer refractory bricks 6, 6 ... It is composed of a brick lower support 11, a horizontal reinforcing body 9 that supports the brick upper support 8, an upper refractory 15 that covers the brick upper support 8, and the like.
 芯金3は、一定の厚さ(25mm)の金属(鋼鉄)板によって、所定の大きさ(内径770mm×高さ800mm)の円筒状に形成されている。なお、芯金3の上端面は、外下がりに傾斜したテーパ状になっている。そして、芯金3の下端際の内側には、内側耐火物層2を支えるための落下抑止体10が、一定幅の円環状(ドーナツ板状)に設けられている(芯金3の下端際の内側に溶接されている)。 The core metal 3 is formed of a metal (steel) plate having a certain thickness (25 mm) into a cylindrical shape having a predetermined size (inner diameter 770 mm × height 800 mm). The upper end surface of the core metal 3 has a tapered shape that is inclined downward. Inside the lower end of the core metal 3, a fall prevention body 10 for supporting the inner refractory layer 2 is provided in an annular shape (doughnut plate shape) having a constant width (at the lower end of the core metal 3). (Welded inside).
 一方、芯金3の下端際の外側には、外側耐火レンガ6,6・・を支えるための環状のレンガ下部支持体11が設けられている。レンガ下部支持体11は、外側耐火レンガ6,6・・の下端に合致した一定幅の円環状(ドーナツ板状)に形成されており、芯金3の下端際の外側に溶接されている。なお、レンガ下部支持体11の上面は、落下抑止体10の上面よりも下方に位置している。また、芯金3の円筒状の本体の下端面、落下抑止体10およびレンガ下部支持体11の下面には、それぞれ、鋼鉄(ステンレス)によってV字状に形成されたスタッド12,12・・が付設されている。 On the other hand, on the outside near the lower end of the core metal 3, an annular brick lower support 11 for supporting the outer refractory bricks 6, 6, ... Is provided. The brick lower support 11 is formed in an annular shape (doughnut plate shape) having a constant width that matches the lower ends of the outer refractory bricks 6, 6, ..., And is welded to the outside near the lower end of the core metal 3. The upper surface of the brick lower support 11 is located below the upper surface of the fall restraint body 10. Further, studs 12, 12, ... Formed in a V shape by steel (stainless steel) are formed on the lower end surface of the cylindrical main body of the core metal 3, the lower surface of the fall restraint body 10 and the brick lower support 11, respectively. It is attached.
 また、内側耐火物層2は、上段耐火レンガ2a,2a・・および下段耐火レンガ2b,2b・・によって形成されている。それらの上段耐火レンガ2a,2a・・および下段耐火レンガ2b,2b・・は、マグネシア-クロム質材によって、台形状の水平断面を有する縦長な四角柱状に形成されている。そして、内側耐火物層2の上部においては、各上段耐火レンガ2a,2a・・を円周状に組み付けることによって、所定の厚み(外径700mm×内径400mm)を有する円筒状体が形成されている。一方、内側耐火物層2の下部においては、各下段耐火レンガ2b,2b・・を円周状に組み付けることによって、同様の厚み(外径700mm×内径400mm)を有する円筒状体が形成されている。 Further, the inner refractory layer 2 is formed by the upper refractory bricks 2a, 2a ... and the lower refractory bricks 2b, 2b ... The upper refractory bricks 2a, 2a ... And the lower refractory bricks 2b, 2b ... Are formed of a magnesia-chromic material into a vertically long square columnar having a trapezoidal horizontal cross section. Then, in the upper part of the inner refractory layer 2, by assembling the upper refractory bricks 2a, 2a ... In a circumferential shape, a cylindrical body having a predetermined thickness (outer diameter 700 mm x inner diameter 400 mm) is formed. There is. On the other hand, in the lower part of the inner refractory layer 2, by assembling the lower refractory bricks 2b, 2b ... In a circumferential shape, a cylindrical body having the same thickness (outer diameter 700 mm × inner diameter 400 mm) is formed. There is.
 そして、下段耐火レンガ2b,2b・・からなる円柱状体の上に、上段耐火レンガ2a,2a・・からなる円柱状体が、通し目地にならないように積層された状態になっている。なお、円周状に組み付けられた各下段耐火レンガ2b,2b・・においては、所定の間隔で(円周に沿って1個おきに)貫通孔13,13・・が上下互い違いに設けられており、金属パイプ5の先端部と連通した状態になっている。また、内側耐火物層2(すなわち、上段耐火レンガ2a,2a・・および下段耐火レンガ2b,2b・・)の外周面と芯金3の内周面との隙間を埋めるように、内側不定形耐火物(キャスタブル)4が充填されている。 Then, the columnar body made of the upper refractory bricks 2a, 2a ... is laminated on the columnar body made of the lower refractory bricks 2b, 2b ... In each of the lower refractory bricks 2b, 2b ... Assembled in a circumferential shape, through holes 13, 13 ... Are provided alternately at predetermined intervals (every other along the circumference). It is in a state of communicating with the tip of the metal pipe 5. Further, the inner irregular shape is formed so as to fill the gap between the outer peripheral surface of the inner refractory layer 2 (that is, the upper refractory bricks 2a, 2a ... and the lower refractory bricks 2b, 2b ...) and the inner peripheral surface of the core metal 3. It is filled with refractory material (castable) 4.
 また、各外側耐火レンガ6,6・・は、マグネシアカーボン質材によって、台形状の水平断面を有する縦長な四角柱状に形成されている。各外側耐火レンガ6,6・・の上側には、外下がりの傾斜面が設けられており、下側には、外上がりの傾斜面が設けられている。それらの上側の傾斜面および下側の傾斜面は、水平面に対して45°の角度を成した状態になっている。 Further, each of the outer refractory bricks 6, 6 ... Is formed of a magnesia carbon material into a vertically long square columnar having a trapezoidal horizontal cross section. An outwardly descending inclined surface is provided on the upper side of each of the outer refractory bricks 6, 6, ..., And an outwardly ascending inclined surface is provided on the lower side. The upper inclined surface and the lower inclined surface are in a state of forming an angle of 45 ° with respect to the horizontal plane.
 そして、各外側耐火レンガ6,6・・は、芯金3の外側において、円周状に組み付けられることによって、所定の厚み(外径1000mm×内径850mm)を有する円筒状体を形成した状態になっている。さらに、そのように円周状に組み付けられた外側耐火レンガ6,6・・の内面と芯金3の外周面との間の隙間を埋めるように、不定形耐火物(アルミナ-マグネシア系)が充填された状態になっている。 Then, each of the outer refractory bricks 6, 6 ... Is assembled in a circumferential shape on the outside of the core metal 3 to form a cylindrical body having a predetermined thickness (outer diameter 1000 mm x inner diameter 850 mm). It has become. Further, an amorphous refractory (alumina-magnesia type) is provided so as to fill the gap between the inner surface of the outer refractory bricks 6, 6 ... It is in a filled state.
 一方、水平補強体9は、一定幅で一定厚みの円環状(ドーナツ板状)に形成されており、芯金3の上端際の外側に水平状に固着(溶接)されている。また、レンガ上部支持体8は、傾斜状支持部16が一定幅で一定厚みの外下がりに傾斜した円環状(円錐台の外周面状)に形成されており、その傾斜状支持部16の外周縁に、一定幅の係止片17が、鉛直下向きに突出するように連設されている。なお、傾斜状支持部16は、水平面に対して45°傾斜した状態になっている。そして、レンガ上部支持体8は、基端の内周縁の部分を、水平補強体9の基端際(内周縁際)の下面に溶接した状態で水平補強体9に固着されている。 On the other hand, the horizontal reinforcing body 9 is formed in an annular shape (doughnut plate shape) having a constant width and a constant thickness, and is horizontally fixed (welded) to the outside near the upper end of the core metal 3. Further, the brick upper support 8 is formed in an annular shape (outer peripheral surface of a truncated cone) in which the inclined support portion 16 is inclined outward with a constant width and a constant thickness, and is outside the inclined support portion 16. Locking pieces 17 having a constant width are continuously provided on the peripheral edge so as to project vertically downward. The inclined support portion 16 is in a state of being inclined by 45 ° with respect to the horizontal plane. The brick upper support 8 is fixed to the horizontal reinforcing body 9 in a state where the inner peripheral edge portion of the base end is welded to the lower surface near the base end (inner peripheral edge) of the horizontal reinforcing body 9.
 さらに、レンガ上部支持体8の上面と水平補強体9の下面とを連結するように、所定の径を有する円柱状の補強支持体18,18・・が、円周状に等間隔に(芯金3の中心に対して等角度毎に)設けられている。さらに、水平補強体9の上面、レンガ上部支持体8の傾斜状支持部16の上面には、それぞれ、上部耐火物15の脱落を防止するためのスタッド14,14・・が突設されている。そして、上記の如く水平補強体9と一体になったレンガ上部支持体8が、傾斜状支持部16の下面で外側耐火レンガ6,6・・の上面を押止し、係止片17で外側耐火レンガ6,6・・の外面を係止した状態になっている。 Further, columnar reinforcing supports 18, 18 ... Having a predetermined diameter are arranged at equal intervals (cores) in a circumferential shape so as to connect the upper surface of the brick upper support 8 and the lower surface of the horizontal reinforcing body 9. It is provided at equal angles to the center of the gold 3. Further, studs 14, 14 ... To prevent the upper refractory 15 from falling off are provided on the upper surface of the horizontal reinforcing body 9 and the upper surface of the inclined support portion 16 of the brick upper support 8, respectively. .. Then, as described above, the brick upper support 8 integrated with the horizontal reinforcing body 9 presses the upper surface of the outer refractory bricks 6, 6 ... On the lower surface of the inclined support portion 16, and the locking piece 17 is used on the outer side. The outer surfaces of the refractory bricks 6, 6 ... are locked.
 そして、レンガ上部支持体8の上側を覆い、水平補強体9を包み込むように、不定形耐火物(アルミナ系キャスタブル)からなる上部耐火物15が形成されており、外周面が円柱状になっている。図4は、レンガ上部支持体8の設置部分を拡大して示したものであり、上部耐火物15を構成している不定形耐火物は、レンガ上部支持体8の先端(下端)の係止片17の外面および下端面をも覆った状態になっている。そして、係止片17の外側に位置した不定形耐火物、および、係止片17の下端面の下側に位置した不定形耐火物は、いずれも約5mmの厚みを有している。 Then, an upper refractory 15 made of an amorphous refractory (alumina-based castable) is formed so as to cover the upper side of the brick upper support 8 and wrap the horizontal reinforcing body 9, and the outer peripheral surface becomes cylindrical. There is. FIG. 4 is an enlarged view of the installation portion of the brick upper support 8, and the amorphous refractory constituting the upper refractory 15 is locked at the tip (lower end) of the brick upper support 8. The outer surface and the lower end surface of the piece 17 are also covered. The amorphous refractory located outside the locking piece 17 and the amorphous refractory located below the lower end surface of the locking piece 17 both have a thickness of about 5 mm.
 一方、芯金3の上端際には、リフトガス(アルゴンガス)を吐出するための金属パイプ5,5・・が設けられている。それらの金属パイプ5,5・・は、略L字状に屈曲した吐出部と鉛直方向に伸張した中継部とからなるものである。そして、吐出部の上側の部分は、不定形耐火物15から上方へ鉛直に突出した状態になっており、吐出部の下側の部分は、芯金を貫通して、中継部の上端に連結された状態になっている。そして、中継部の下端が、下段耐火レンガ2b,2b・・に穿設された貫通孔13,13・・と連通した状態になっている。 On the other hand, at the upper end of the core metal 3, metal pipes 5, 5, ... For discharging lift gas (argon gas) are provided. These metal pipes 5, 5, ... Consists of a discharge portion bent in a substantially L shape and a relay portion extended in the vertical direction. The upper portion of the discharge portion is in a state of vertically projecting upward from the amorphous refractory material 15, and the lower portion of the discharge portion penetrates the core metal and is connected to the upper end of the relay portion. It is in the state of being. Then, the lower end of the relay portion is in a state of communicating with the through holes 13, 13 ... drilled in the lower refractory bricks 2b, 2b ...
 さらに、芯金3の下端際には、不定形耐火物(アルミナ-マグネシア系キャスタブル)からなる肉厚な円筒状の下部耐火物7が形成されており、芯金3の下端際の内外周、内側耐火物層2の下面、落下抑止体10の下面、レンガ下部支持体11の下面、外側耐火レンガ6,6・・の下側の傾斜面を一体的に覆った状態になっている。そして、当該下部耐火物7の内周面は、内側耐火物層2の内周面と面一になっており、下部耐火物7の外周面は、外側耐火レンガ6,6・・の外周面と面一になっている。また、外側耐火レンガ6,6・・の内面と芯金3の外周面との隙間を埋めた不定形耐火物と、下部耐火物7を構成する不定形耐火物とが一体になっている。 Further, a thick cylindrical lower refractory 7 made of an amorphous refractory (alumina-magnesia castable) is formed at the lower end of the core metal 3, and the inner and outer circumferences of the lower end of the core metal 3 are formed. The lower surface of the inner refractory layer 2, the lower surface of the fall restraint body 10, the lower surface of the brick lower support 11, and the lower inclined surface of the outer refractory bricks 6, 6, ... Are integrally covered. The inner peripheral surface of the lower refractory 7 is flush with the inner peripheral surface of the inner refractory layer 2, and the outer peripheral surface of the lower refractory 7 is the outer peripheral surface of the outer refractory bricks 6, 6, ... It is flush with each other. Further, the amorphous refractory material that fills the gap between the inner surface of the outer refractory bricks 6, 6 ... And the outer peripheral surface of the core metal 3 and the amorphous refractory material that constitutes the lower refractory material 7 are integrated.
<浸漬管の使用方法>
 図5は、上記の如く構成された浸漬管1の使用方法の一例を示したものである。浸漬管1は、2個一対で、真空脱ガス装置Mの下端際に固着されている環流管Cに接続され、下端際の部分を取鍋24内の溶湯(溶融させた鉄)Sに浸漬させた状態で使用される。そのように設置された2個の浸漬管1,1の内の片方(図5の左側の浸漬管1a)は、上昇管として機能し、他方(図5の右側の浸漬管1b)は、下降管として機能する。
<How to use the immersion tube>
FIG. 5 shows an example of how to use the immersion tube 1 configured as described above. A pair of dipping pipes 1 are connected to a recirculation pipe C fixed at the lower end of the vacuum degassing device M, and the portion near the lower end is immersed in the molten metal (melted iron) S in the pan 24. It is used in the state where it is made. One of the two immersion tubes 1 and 1 so installed (the immersion tube 1a on the left side of FIG. 5) functions as an ascending tube, and the other (the immersion tube 1b on the right side of FIG. 5) descends. Functions as a tube.
 そして、真空脱ガス装置Mにおいて、真空脱ガス装置Mの上部槽22および下部槽23を真空状態にし、配管を介して上昇管である浸漬管1aに不活性ガス(アルゴンガス等)を吹き込むと、取鍋24内の溶湯が、下部槽23側に引き込まれて上昇管である浸漬管1aの溶湯通路(内側耐火物層2の内部)Rを上昇し、その後、下降管である浸漬管1bの溶湯通路Rを下降して取鍋24に戻って環流する。かかる環流の過程において、溶湯の脱ガスが行われる。 Then, in the vacuum degassing device M, the upper tank 22 and the lower tank 23 of the vacuum degassing device M are put into a vacuum state, and an inert gas (argon gas or the like) is blown into the immersion pipe 1a which is an ascending pipe via the pipe. , The molten metal in the intake pot 24 is drawn into the lower tank 23 side and rises the molten metal passage (inside the inner refractory layer 2) R of the immersion pipe 1a which is an ascending pipe, and then the immersion pipe 1b which is a descending pipe. It descends the molten metal passage R of the above and returns to the pan 24 to recirculate. In the process of such recirculation, the molten metal is degassed.
 浸漬管1a,1bにおいては、上記の如く真空脱ガス装置Mに装着されて脱ガスを実施する際に上部の外側まで熱負荷が加わっても、その熱負荷が、上部耐火物15を構成している不定形耐火物(アルミナ系キャスタブル)によって吸収されるため、レンガ上部支持体8の変形や溶融が高い精度で防止される。 In the immersion tubes 1a and 1b, even if a heat load is applied to the outside of the upper part when the vacuum degassing device M is attached to the vacuum degassing device M as described above and the degassing is performed, the heat load constitutes the upper refractory material 15. Since it is absorbed by the irregular refractory (alumina-based castable), deformation and melting of the brick upper support 8 are prevented with high accuracy.
<浸漬管の効果>
 浸漬管1は、上記の如く、円筒状に形成された鉄製の芯金3と、その芯金3の内側に設けられた内側耐火物層2(すなわち、上段耐火レンガ2a,2a・・および下段耐火レンガ2b,2b・・)と、芯金3の外側に円周状に配置された複数の外側耐火レンガ6,6・・と、外側耐火レンガ6,6・・の下端際を支えるためのレンガ下部支持体11と、外側耐火レンガ6,6・・の上端際を支えるためのレンガ上部支持体8とを備えているとともに、そのレンガ上部支持体8の上側が、不定形耐火物(アルミナ系キャスタブル)15によって覆われている。したがって、浸漬管1においては、レンガ上部支持体8が飛散したスプラッシュ(溶鋼の飛沫)を浴びたりせず、輻射熱等の影響を受けにくい上、スラグの除去作業の際に、その衝撃がレンガ上部支持体8に伝わりにくいので、レンガ上部支持体8の設置部分が損傷しにくい。したがって、浸漬管1によれば、耐用寿命を長くすることができる上、頻繁なメンテナンスが不要となるので、維持費用を低く抑えることができる。
<Effect of immersion tube>
As described above, the immersion tube 1 includes an iron core metal 3 formed in a cylindrical shape and an inner refractory layer 2 (that is, upper refractory bricks 2a, 2a ... And lower stage) provided inside the core metal 3. (2b, 2b ...), a plurality of outer refractory bricks 6, 6 ... arranged in a circumferential shape on the outside of the core metal 3, and to support the lower end edge of the outer refractory bricks 6, 6 ... A brick lower support 11 and a brick upper support 8 for supporting the upper ends of the outer refractory bricks 6, 6 ... Are provided, and the upper side of the brick upper support 8 is an amorphous refractory (alumina). System castable) 15 covered. Therefore, in the immersion pipe 1, the brick upper support 8 is not exposed to scattered splashes (splashes of molten steel) and is not easily affected by radiant heat or the like, and the impact is applied to the upper part of the brick during the slag removal work. Since it is difficult to transmit to the support 8, the installation portion of the brick upper support 8 is not easily damaged. Therefore, according to the immersion tube 1, the service life can be extended and frequent maintenance is not required, so that the maintenance cost can be kept low.
 また、浸漬管1は、レンガ上部支持体8が外下がりに傾斜した円環状に設けられたものであるため、使用時に外側耐火レンガ6,6・・に放射方向に拡散しようとする熱膨張応力が加わった場合でも、その熱膨張応力を効果的に抑えて、外側耐火レンガ6,6・・の脱落を防止することができる。 Further, since the immersion tube 1 is provided with the brick upper support 8 in an annular shape inclined outward, the thermal expansion stress that tends to diffuse in the radial direction to the outer refractory bricks 6, 6 ... Even when the above is added, the thermal expansion stress can be effectively suppressed and the outer refractory bricks 6, 6 ... Can be prevented from falling off.
 さらに、浸漬管1は、レンガ上部支持体8の先端に、外側耐火レンガ6,6・・の側面を係止するための係止片17が鉛直下向きに連設されているとともに、その係止片17の外側の部分が不定形耐火物(アルミナ系キャスタブル)15によって覆われているため、使用時に係止片17が飛散したスプラッシュを浴びたりしない上、輻射熱等の影響を受けにくいため、係止片17が外側耐火レンガ6,6・・の側面を係止し続けることができる。したがって、浸漬管1によれば、外側耐火レンガ6,6・・の脱落を長期間に亘って効果的に防止することができる。 Further, in the immersion pipe 1, a locking piece 17 for locking the side surfaces of the outer refractory bricks 6, 6 ... Is connected vertically downward to the tip of the brick upper support 8 and the locking thereof. Since the outer part of the piece 17 is covered with an amorphous refractory (alumina-based castable) 15, the locking piece 17 is not exposed to scattered splashes during use and is not easily affected by radiant heat. The piece 17 can continue to lock the sides of the outer refractory bricks 6, 6, ... Therefore, according to the immersion pipe 1, it is possible to effectively prevent the outer refractory bricks 6, 6, ... From falling off over a long period of time.
 加えて、浸漬管1は、レンガ上部支持体8の上面に、不定形耐火物15の脱落を防止するためのスタッド14a,14a・・が突設されているため、レンガ上部支持体8の上側を覆った不定形耐火物15が脱落しにくいので、きわめて長期間に亘って高い精度でレンガ上部支持体8の設置部分の損傷を防止することができる。 In addition, since the immersion pipe 1 has studs 14a, 14a ... Protruding on the upper surface of the brick upper support 8 to prevent the amorphous refractory 15 from falling off, the upper side of the brick upper support 8 is provided. Since the amorphous refractory 15 that covers the brick is hard to fall off, it is possible to prevent damage to the installation portion of the brick upper support 8 with high accuracy for an extremely long period of time.
<浸漬管の変更例>
 本発明に係る浸漬管は、上記した実施形態の態様に何ら限定されるものではなく、芯金、レンガ上部支持体、レンガ下部支持体、水平補強体、内側耐火物層、外側耐火レンガ等の材質、形状、構造、大きさ等の構成を、本発明の趣旨を逸脱しない範囲で、必要に応じて適宜変更することができる。
<Example of changing the immersion tube>
The immersion pipe according to the present invention is not limited to the embodiment described above, and includes a core metal, a brick upper support, a brick lower support, a horizontal reinforcing body, an inner refractory layer, an outer refractory brick, and the like. The composition of the material, shape, structure, size, etc. can be appropriately changed as necessary without departing from the spirit of the present invention.
 たとえば、本発明に係る浸漬管は、上記実施形態の如く、レンガ上部支持体の上側を覆う不定形耐火物(すなわち、上部耐火物を構成する不定形耐火物)がアルミナ系キャスタブルであるものに限定されず、レンガ上部支持体の上側を覆う不定形耐火物をアルミナ-マグネシア系キャスタブル等のアルミナ系キャスタブル以外の素材に変更することも可能である。なお、上記実施形態の如く、レンガ上部支持体の上側を覆う不定形耐火物をアルミナ系キャスタブル等の高強度の素材とした場合には、レンガ上部支持体の変形・溶融をより高い精度で防止することが可能となる、というメリットがある。 For example, in the immersion pipe according to the present invention, as in the above embodiment, the amorphous refractory covering the upper side of the brick upper support (that is, the amorphous refractory constituting the upper refractory) is an alumina-based castable. It is also possible to change the amorphous refractory covering the upper side of the brick upper support to a material other than the alumina-based castable such as the alumina-magnesia-based castable. When the amorphous refractory covering the upper side of the brick upper support is made of a high-strength material such as an alumina-based castable as in the above embodiment, the brick upper support is prevented from being deformed and melted with higher accuracy. There is a merit that it becomes possible to do.
 また、本発明に係る浸漬管は、上記実施形態の如く、下部耐火物を構成する不定形耐火物がアルミナ-マグネシア系キャスタブルであるものに限定されず、下部耐火物を構成する不定形耐火物をアルミナ系キャスタブル等の別の素材に変更することも可能である。なお、上記実施形態の如く、下部耐火物を構成する不定形耐火物をアルミナ-マグネシア系キャスタブル等の耐スポーリング性が高い素材とした場合には、芯金の下部の変形をより高い精度で防止することが可能となる、というメリットがある。 Further, the immersion pipe according to the present invention is not limited to the amorphous refractory constituting the lower refractory being an alumina-magnesia castable as in the above embodiment, and the amorphous refractory constituting the lower refractory. Can be changed to another material such as alumina-based castable. When the amorphous refractory constituting the lower refractory is made of a material having high spalling resistance such as an alumina-magnesia castable as in the above embodiment, the deformation of the lower part of the core metal is performed with higher accuracy. There is an advantage that it can be prevented.
 さらに、本発明に係る浸漬管は、上記実施形態の如く、内側耐火物層がマグネシア-クロム質材からなるものに限定されず、操業条件等に応じて、内側耐火物層をマグネシア-カーボン質材等のマグネシア-クロム質材以外の素材からなるもの等に変更することも可能である。 Further, the immersion pipe according to the present invention is not limited to the one in which the inner refractory layer is made of magnesia-chromium material as in the above embodiment, and the inner refractory layer is made of magnesia-carbon material depending on the operating conditions and the like. It is also possible to change to a material other than magnesia-chromic material such as wood.
 また、本発明に係る浸漬管は、上記実施形態の如く、レンガ上部支持体が傾斜状支持部を水平補強体に固着させたもの(溶接したもの)に限定されず、傾斜状支持部が芯金に直接的に固着させたもの等に変更することも可能である。なお、上記実施形態の如く、レンガ上部支持体の傾斜状支持部を水平補強体に固着させたものとした場合には、上部補強体を構成する不定形耐火物の脱落をより効果的に防止することが可能となる上、浸漬管の上部から伝わる熱を水平補強体が効果的に遮断するため、傾斜状支持部の変形・溶融をより高い精度で防止することが可能となる。さらに、レンガ上部支持体の上面と水平補強体の下面とを連結するように補強支持体を設ける場合には、当該補強支持体は、上記実施形態の如く、鉛直な棒状体(円柱状体)に限定されず、一定厚みの円筒状(扁平な円筒状)に一体的に形成されたもの、あるいは、レンガ上部支持体の周状の上面に沿って所定の間隔(等間隔あるいは非等間隔)で設置(溶接)される複数の三角形状(外向きに次第に幅広になる三角形状)や台形状(外向きに次第に幅広になる台形状)等の板体等でも良い。 Further, the immersion pipe according to the present invention is not limited to the one in which the brick upper support has the inclined support portion fixed to the horizontal reinforcing body (welded) as in the above embodiment, and the inclined support portion is the core. It is also possible to change to something that is directly fixed to gold. When the inclined support portion of the brick upper support is fixed to the horizontal reinforcing body as in the above embodiment, the amorphous refractory constituting the upper reinforcing body is more effectively prevented from falling off. In addition, since the horizontal reinforcing body effectively blocks the heat transferred from the upper part of the immersion tube, it is possible to prevent deformation and melting of the inclined support portion with higher accuracy. Further, when a reinforcing support is provided so as to connect the upper surface of the brick upper support and the lower surface of the horizontal reinforcing body, the reinforcing support is a vertical rod-shaped body (cylindrical body) as in the above embodiment. It is not limited to the above, but is integrally formed in a cylindrical shape (flat cylindrical shape) having a constant thickness, or at predetermined intervals (equal intervals or non-equal intervals) along the circumferential upper surface of the brick upper support. It may be a plate such as a plurality of triangular shapes (triangular shapes that gradually widen outward) or trapezoidal shapes (trapezoidal shapes that gradually widen outward) that are installed (welded) in.
 さらに、本発明に係る浸漬管を、上記実施形態の如く、レンガ上部支持体の係止片の外側および/または下側を不定形耐火物で覆ったものとする場合には、係止片の外側および/または下側を覆う不定形耐火物の厚みを、必要に応じて適宜変更することができ、その厚みを5~15mmの範囲に調整した場合には、不必要に多くの不定形耐火物を用いることなく、係止片の変形・溶融を効果的に防止することが可能となる。 Further, when the immersion pipe according to the present invention is covered with an amorphous refractory on the outside and / or the lower side of the locking piece of the brick upper support as in the above embodiment, the locking piece The thickness of the amorphous refractory covering the outside and / or the underside can be changed as needed, and when the thickness is adjusted to the range of 5 to 15 mm, an unnecessarily large amount of amorphous refractory It is possible to effectively prevent deformation and melting of the locking piece without using an object.
 加えて、本発明に係る浸漬管は、上記実施形態の如く、金属製の棒状体をV字状に屈曲させたスタッドを芯金、レンガ上部支持体、レンガ下部支持体、落下抑止体等に突設したものに限定されず、スタッドの形状を、板状の折り返しやY字状の屈曲等に変更することも可能である。また、本発明に係る浸漬管は、熱負荷によって芯金の下端際が開く事態を防止するために、下端際の外周に金属からなる帯状あるいは棒状で単一あるいは複数の環状体を巻回させたもの等に変更することも可能である。 In addition, in the immersion pipe according to the present invention, as in the above embodiment, a stud obtained by bending a metal rod-shaped body into a V shape is used as a core metal, a brick upper support, a brick lower support, a fall prevention body, or the like. The shape of the stud is not limited to the protruding one, and it is possible to change the shape of the stud to a plate-shaped folded back, a Y-shaped bent, or the like. Further, in the dipping tube according to the present invention, in order to prevent the lower end edge of the core metal from opening due to a heat load, a single or a plurality of annular bodies made of metal in a band shape or a rod shape are wound around the outer periphery of the lower end edge. It is also possible to change it to something else.
 また、本発明に係る浸漬管は、上記実施形態の如く、レンガ上部支持体の傾斜支持部が水平面に対して45°の角度を成したもの(すなわち、各外側耐火レンガの上側の傾斜面が水平面に対して45°の角度を成したもの)に限定されず、レンガ上部支持体の傾斜支持部の傾斜角度(すなわち、各外側耐火レンガの上側の傾斜面がの傾斜角度)を、概ね0~60°の範囲内で必要に応じて適宜変更することができる。加えて、本発明に係る浸漬管は、上記実施形態の如く、下部耐火物の外周面と外側耐火レンガの外周面とが面一になっているものに限定されず、下部耐火物と外側耐火レンガの境界から溶鋼が浸入するのを防止する目的で外側耐火レンガの下側(下部)を下部耐火物で覆ったもの等に変更することも可能である。 Further, in the immersion pipe according to the present invention, as in the above embodiment, the inclined support portion of the brick upper support has an angle of 45 ° with respect to the horizontal plane (that is, the inclined surface on the upper side of each outer fireproof brick is formed. Not limited to an angle of 45 ° with respect to the horizontal plane), the inclination angle of the inclined support portion of the brick upper support (that is, the inclination angle of the upper inclined surface of each outer fireproof brick) is approximately 0. It can be changed as needed within the range of ~ 60 °. In addition, the immersion pipe according to the present invention is not limited to the one in which the outer peripheral surface of the lower refractory and the outer peripheral surface of the outer refractory brick are flush with each other as in the above embodiment, and the lower refractory and the outer refractory are not limited to the same. It is also possible to change the lower side (lower part) of the outer refractory brick to one covered with a lower refractory material for the purpose of preventing molten steel from infiltrating from the boundary of the brick.
 本発明に係る浸漬管は、上記の如く優れた効果を奏するものであるので、溶鋼を二次精錬する際に真空脱ガス装置に装着して上昇管あるいは下降管として機能させる部材等として好適に用いることができる。 Since the immersion pipe according to the present invention exerts an excellent effect as described above, it is suitable as a member or the like which is attached to a vacuum degassing device to function as an ascending pipe or a descending pipe when secondary refining molten steel. Can be used.
 1(1a,1b)・・浸漬管
 2・・内側耐火物層
 2a・・上段耐火レンガ
 2b・・下段耐火レンガ
 3・・芯金
 4・・内側不定形耐火物
 6・・外側耐火レンガ
 8・・レンガ上部支持体
 9・・水平補強体
 11・・レンガ下部支持体
 14・・スタッド
 15・・上部耐火物
 M・・真空脱ガス装置
1 (1a, 1b) ・ ・ Immersion pipe 2 ・ ・ Inner refractory layer 2a ・ ・ Upper refractory brick 2b ・ ・ Lower refractory brick 3 ・ ・ Core metal 4 ・ ・ Inner irregular refractory 6 ・ ・ Outer refractory brick 8 ・・ Brick upper support 9 ・ ・ Horizontal reinforcement 11 ・ ・ Brick lower support 14 ・ ・ Stud 15 ・ ・ Upper refractory M ・ ・ Vacuum degassing device

Claims (3)

  1.  溶鋼真空脱ガス装置に上昇管あるいは下降管として用いられる溶鋼処理用の浸漬管であって、
     円筒状に形成された鉄製の芯金と、
     その芯金の内側に設けられた内側耐火物層と、
     前記芯金の外側に円周状に配置された複数の外側耐火レンガと、
     前記芯金の下端際に設けられた前記外側耐火レンガの下端際を支えるためのレンガ下部支持体と、
     前記芯金の上端際に設けられた前記外側耐火レンガの上端際を支えるためのレンガ上部支持体とを備えているとともに、
     前記レンガ上部支持体が、外下がりに傾斜した円環状に設けられたものであり、そのレンガ上部支持体の上側が、不定形耐火物によって覆われており、かつ、
     前記レンガ上部支持体の先端に、前記外側耐火レンガの側面を係止するための係止片が鉛直下向きに連設されているとともに、その係止片の外側の部分が不定形耐火物によって覆われていることを特徴とする浸漬管。
    An immersion pipe for molten steel processing used as an ascending pipe or a descending pipe in a molten steel vacuum degassing device.
    A cylindrical iron core and
    The inner refractory layer provided inside the core metal,
    A plurality of outer refractory bricks arranged in a circumferential shape on the outer side of the core metal,
    A brick lower support for supporting the lower end of the outer refractory brick provided near the lower end of the core metal, and a brick lower support.
    It is provided with a brick upper support for supporting the upper end of the outer refractory brick provided near the upper end of the core metal, and is provided.
    The brick upper support is provided in an annular shape that is inclined downward, and the upper side of the brick upper support is covered with an amorphous refractory and that the brick upper support is covered with an amorphous refractory.
    A locking piece for locking the side surface of the outer refractory brick is connected vertically downward to the tip of the brick upper support, and the outer portion of the locking piece is covered with an amorphous refractory. Immersion tube characterized by being bricked.
  2.  前記レンガ上部支持体の上面に、不定形耐火物の脱落を防止するためのスタッドが突設されていることを特徴とする請求項1に記載の浸漬管。 The immersion pipe according to claim 1, wherein a stud for preventing the irregular refractory from falling off is provided on the upper surface of the brick upper support.
  3.  前記芯金が、フランジレスタイプのものであることを特徴とする請求項1、または2に記載の浸漬管。 The immersion tube according to claim 1 or 2, wherein the core metal is of a flangeless type.
PCT/JP2019/046462 2019-11-27 2019-11-27 Dip tube for molten steel processing WO2021106120A1 (en)

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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5024421A (en) * 1990-05-08 1991-06-18 Usx Corporation Interlocking snorkel refractory
JPH0539522A (en) * 1991-08-02 1993-02-19 Toshiba Ceramics Co Ltd Lance pipe for injecting gas
JPH0734119A (en) * 1993-07-19 1995-02-03 Daido Steel Co Ltd Immersion pipe for vacuum degassing device
JP2012167868A (en) * 2011-02-15 2012-09-06 Tokyo Yogyo Co Ltd Stirring device
JP2013234346A (en) * 2012-05-08 2013-11-21 Tokyo Yogyo Co Ltd Dip tube or lower tank of vacuum degassing device

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5024421A (en) * 1990-05-08 1991-06-18 Usx Corporation Interlocking snorkel refractory
JPH0539522A (en) * 1991-08-02 1993-02-19 Toshiba Ceramics Co Ltd Lance pipe for injecting gas
JPH0734119A (en) * 1993-07-19 1995-02-03 Daido Steel Co Ltd Immersion pipe for vacuum degassing device
JP2012167868A (en) * 2011-02-15 2012-09-06 Tokyo Yogyo Co Ltd Stirring device
JP2013234346A (en) * 2012-05-08 2013-11-21 Tokyo Yogyo Co Ltd Dip tube or lower tank of vacuum degassing device

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