JP2017197818A - Gas blowing plug - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent breakage of a gas blowing plug in the vicinity of a junction area between a bottom-part steel plate and a side-part steel plate, when being pulled out.SOLUTION: A monolithic refractory part 12 is provided in a part of the inner side of a bottom-part steel plate 14 of a gas blowing plug, and a single or a plurality of bottom-part projection 19 including a face 19a that is in a non-parallel direction with respect to a vertical-axis direction of the gas blowing plug is placed in the monolithic refractory part 12 by being connected to the bottom-part steel plate 14.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a structure of a gas blowing plug used for blowing gas from the bottom in a molten steel ladle (molten steel container) such as a converter or an electric furnace.

  In the removal after use of such a gas blowing plug, a method is adopted in which a pulling device is connected to a gas introduction pipe connected to the bottom of the plug and pulled downward to be pulled out. However, at the time of this drawing, the gas introduction pipe itself or its surroundings may be destroyed, and most of the gas blowing plug main body part may remain in the ladle.

  As a countermeasure, for example, Patent Document 1 is characterized in that an extraction auxiliary jig is provided below a porous plug as a gas blowing plug separately from a gas introduction pipe also serving as an extraction jig. A porous plug is disclosed.

Microfilm of Japanese Utility Model No. Sho 63-119583 (Japanese Utility Model Laid-Open No. 2-42754)

  In the above-mentioned Patent Document 1, the force applied to the gas introduction pipe is reduced by the mechanical force of the extraction auxiliary jig installed in the lower part of the porous plug. Destruction can be avoided. However, at the time of drawing, not only the gas introduction pipe itself or its surroundings are destroyed, but also, for example, as shown in FIG. 6, the bottom iron plate 14 and side iron plate 15 of the porous plug welded with the gas introduction pipe 17 The vicinity of the joint (welded portion 16) may be destroyed, and the portion above the bottom may remain in the ladle. Such a form of destruction cannot be solved by the installation of the auxiliary jig for extraction in Patent Document 1.

  Therefore, the problem to be solved by the present invention is to prevent the vicinity of the joint portion between the bottom iron plate and the side iron plate of the gas blowing plug from being broken at the time of drawing.

According to the present invention, the following gas blowing plugs 1 to 4 are provided.
1. A gas blowing plug having an outer surface covered with an iron plate and connected to a gas introduction pipe at the bottom, the gas blowing plug having an irregular refractory portion on a part of an inner side of the bottom iron plate, the irregular refractory A gas blowing plug in which one or a plurality of bottom protrusions including a surface in a direction non-parallel to the longitudinal direction of the gas blowing plug are connected to the bottom iron plate.
2. At least one of the bottom protrusions continuously extends upward from the bottom iron plate so as to surround the gas inlet port connected to the gas introduction pipe, and all of the inner peripheral surface and the outer peripheral side thereof. The gas blowing plug according to 1 above, wherein either or both of the surfaces are in close contact with the irregular refractory portion.
3. The gas according to 1 or 2 above, wherein one or a plurality of side protrusions extending from the side iron plate of the gas blowing plug toward the center of the gas blowing plug are disposed in the amorphous refractory portion. Plug for blowing.
4). One or a plurality of connecting portions for connecting the bottom iron plate and the side iron plate inside the irregular refractory portion are installed in the irregular refractory portion. Plug for gas injection.

  According to the present invention, the bottom projecting portion can distribute the force at the time of drawing also to the irregular refractory part in the gas blowing plug, and the bottom iron plate and the side iron plate of the gas blowing plug at the time of drawing. It is possible to prevent the vicinity of the joint portion with the breakage. This also makes it possible to pull out the entire porous plug almost certainly. Furthermore, it is possible to prevent the amorphous refractory portion in the gas blowing plug from being broken or falling off the side iron plate, and the entire gas blowing plug can be pulled out more reliably.

It is an image figure which shows the installation state of the plug for gas blowing which concerns on one Embodiment of this invention in a cross section. It is an image figure which shows the AA end surface of FIG. It is an image figure which shows the plug for gas blowing which concerns on other embodiment of this invention in a cross section. It is an image figure which shows the BB end surface of FIG. It is an image figure which shows the plug for gas blowing which concerns on other embodiment of this invention in a cross section. Same as above. Same as above. It is an image figure which shows the conventional plug for gas blowing in a cross section, (a) is an installation state, (b) shows the example of the destruction state between the bottom iron plate and side iron plate at the time of pulling out a porous plug.

  Embodiments of the present invention will be described below with reference to the drawings.

(Embodiment 1)
FIG. 1 is an image view showing a cross-sectional view of a gas blowing plug according to an embodiment of the present invention, and FIG. 2 is an image view showing an AA end face of FIG.

  As shown in FIG. 1, a porous plug 10 as a gas blowing plug is used by fitting a tuyere brick 30 at the bottom of a molten steel ladle.

  The porous plug 10 is provided with a porous brick 11 at the center in the longitudinal axis direction, and an irregular refractory portion 12 is installed so as to surround the side portion of the porous brick 11, and the porous brick 11 and the irregular refractory portion. 12 constitutes the plug body 13. The plug body 13 has a cylindrical bottom portion and a tapered upper portion (conical frustum shape), and the outer surface of the plug body 13 (at least the bottom portion and the side portion in contact with the outer periphery of the bottom portion) is covered with an iron plate. That is, the bottom portion of the plug body 13 is covered with the bottom iron plate 14, and the side portion of the plug body 13 (at least the side portion contacting the outer periphery of the bottom portion) is covered with the side iron plate 15. Are joined by a weld 16. Further, a gas introduction pipe 17 is connected to the center of the bottom iron plate 14, and the gas introduced from the gas introduction pipe 17 passes through the porous brick 11 from the gas introduction port 18, and the porous brick 11. It is blown into the molten steel in the molten steel ladle from the upper end surface. As described above, the porous plug 10 is provided with the porous brick 11 for gas blowing, and the irregular refractory portion 12 is installed so as to surround the side portion thereof, so that the irregular shape is formed in a part of the inside of the bottom iron plate 14. The structure has a refractory portion 12.

  In such a basic structure, the porous plug 10 of the present invention connects the bottom protrusion 19 including a surface non-parallel to the longitudinal direction of the porous plug in the irregular refractory portion 12 to the bottom iron plate 14. One or a plurality are installed. In the present embodiment, the bottom protrusion 19 has a T-shaped cross section, and the upper side of the T-shape is a surface 19a that is not parallel to the longitudinal direction of the porous plug. Thus, the bottom protrusion 19 installed by connecting (welding) to the bottom iron plate 14 includes the surface 19a in the non-parallel direction, so that the downward pulling force can be dispersed in the amorphous refractory portion 12. Therefore, it is possible to prevent the vicinity of the joint portion (welded portion 16) between the bottom iron plate 14 and the side iron plate 15 of the porous plug 10 from being broken during pulling.

  One or a plurality of such bottom protrusions may be installed at any location in the circumferential direction or the radial direction within the irregular refractory portion 12, but at least one of the bottom protrusions is As in the bottom protrusion 19 of the embodiment, either or both of all the surfaces on the inner peripheral side and all the outer peripheral sides are continuously extended upward from the bottom iron plate so as to surround the gas inlet 18. Is preferably in close contact with the amorphous refractory portion 12. More specifically, the bottom protrusion 19 of the present embodiment has a continuous structure with no gap at the boundary with the bottom iron plate 14 over the entire circumference in the circumferential direction so as to surround the gas inlet port 18. All surfaces on the inner peripheral side and the outer peripheral side are in close contact with the amorphous refractory portion 12. By adopting such a structure, the bottom iron plate 14 is firmly bonded to and closely adhered to the amorphous refractory portion 12, so that gas leakage can also be prevented.

(Embodiment 2)
FIG. 3 is an image view showing a cross-section of a gas blowing plug according to another embodiment of the present invention, and FIG. 4 is an image view showing a BB end face of FIG. In the present embodiment, one or a plurality of side protrusions 20 extending from the side iron plate 14 in the center direction of the horus plug are installed in the indeterminate refractory portion 12. Four side protrusions 20 are installed (welded). Specifically, these four side protrusions 20 are installed at equal intervals in the circumferential direction at the upper part (tapered portion) of the side protrusion 20.

  Since the side iron plate 15 and the irregular refractory part 12 are integrated by installing the side protrusion 20 in this way, only the irregular refractory part 12 (plug main body 13) together with the bottom iron plate 14 when being pulled out. It is possible to prevent the occurrence of a situation in which the side iron plate 15 remains due to falling off.

  In addition, although one side part protrusion part may be sufficient, in order to disperse | distribute a force equally to the whole, it is preferable to disperse | distribute three or more places and to install equally.

(Embodiment 3)
5A to 5C are image views showing in cross section a gas blowing plug according to still another embodiment of the present invention. In the present embodiment, one or a plurality of connecting portions 21 for connecting the bottom iron plate 14 and the side iron plate 15 inside the irregular refractory portion 12 are installed in the irregular refractory portion 12. .

Specifically, in the example of FIG. 5A, the connecting portion 21 is formed by connecting the non-parallel surface 19a and the side iron plate 15 with a bar or a rib member using the bottom protrusion 19. Yes.
In the example of FIG. 5B, the connection part 21 is comprised by utilizing the bottom part protrusion part 19 and the side part protrusion part 20, and connecting these with a bar material or a rib material.
In addition, the location by the side iron plate 15 side of the side protrusion 20 and the connection part 21 shown to FIG. 5B connected with these by the bar material or the rib material is an inclined part (tapered part) of the side iron plate 15. It is more preferable. The reason is that by pulling the inclined portion of the side iron plate 15 downward, the inclined portion of the side iron plate is slightly deformed inward, and is easily separated from the outer tuyere and mortar.
In the example of FIG. 5C, the connecting portion 21 is configured by directly connecting the side protruding portion 20 and the bottom iron plate 14 (the connecting portion 21 is configured without using the bottom protruding portion 19). .

  By installing the connecting portion 21 in this way, the downward pulling force can be directly distributed to the side iron plate 15, and the force is concentrated on the boundary (welded portion 16) between the bottom iron plate 14 and the side iron plate 15. You can avoid that. In addition, although one connection part may be sufficient, in order to disperse | distribute force equally to the whole, it is preferable to disperse | distribute three or more places and to install equally. Moreover, you may comprise a connection part by the continuous plate-shaped surface for the perimeter.

  In the above embodiment, the porous plug 10 using the porous brick 11 is used as one form of the gas blowing plug. However, the present invention can also be applied to a gas blowing plug other than the porous plug. For example, it can be applied to a multi-hole plug provided with a plurality of gas blowing pipes in the vertical direction instead of the porous brick 11.

10 Porous plug (gas injection plug)
DESCRIPTION OF SYMBOLS 11 Porous brick 12 Amorphous refractory part 13 Plug main body 14 Bottom iron plate 15 Side iron plate 16 Welding part 17 Gas introduction pipe 18 Gas introduction port 19 Bottom part projection part 19a Non-parallel direction surface 20 Side part projection part 21 Connection part 30 Tuyere brick

Claims (4)

  A gas blowing plug having an outer surface covered with an iron plate and connected to a gas introduction pipe at the bottom, the gas blowing plug having an irregular refractory portion on a part of an inner side of the bottom iron plate, the irregular refractory A gas blowing plug in which one or a plurality of bottom protrusions including a surface in a direction non-parallel to the longitudinal direction of the gas blowing plug are connected to the bottom iron plate.   At least one of the bottom protrusions continuously extends upward from the bottom iron plate so as to surround the gas inlet port connected to the gas introduction pipe, and all of the inner peripheral surface and the outer peripheral side thereof. The gas blowing plug according to claim 1, wherein either or both of the surfaces are in close contact with the irregular refractory portion.   The side protrusion part extended in the gas blowing plug center direction from the side part iron plate of the gas blowing plug was installed in the said irregular refractory part, or one or more of Claim 1 or Claim 2 installed. Plug for gas injection.   The connection part which connects the said bottom part iron plate and a side part iron plate inside the said irregular-shaped refractory part has installed one or more in the said irregular-shaped refractory part. A plug for gas injection according to the above.

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