JP2554502Y2 - Ladle refining snorkel - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ladle refining snorkel used for cutting slag when a heating agent is added to molten steel in a ladle to add oxygen to the molten steel and raise the temperature of the molten steel.

[0002]

2. Description of the Related Art When ladle refining is performed, it is necessary to compensate for the molten steel temperature. As a method of compensating for the molten steel temperature, a heating agent such as Al or Si is added to the molten steel stored in the ladle, oxygen gas is blown from the bottom of the ladle while an inert gas is blown, and the molten steel is stirred to melt the molten steel temperature. (JP-A-54-149313, JP-A-59-89708)
No., JP-A-61-235506), a linear metal or alloy which is stoichiometrically equivalent to or more than oxygen supply from a top blowing lance while stirring molten steel by introducing an inert gas from the bottom. And the molten metal is melted at the lower end of the lance by contact with the molten steel to raise the temperature of the molten steel.
4-29163) has been proposed. The methods disclosed in JP-A-54-149313, JP-A-59-89708, JP-A-61-235506 and JP-B-54-29163 disclose that the stirring of molten steel is all carried out at the bottom of the ladle. Since the inert gas is blown from the installed porous plug, the refractory erosion of the porous plug and the repair man-hour due to clogging of the porous plug, etc. are increased, and the inert gas flow rate is increased and the stirring is performed. I can't increase my power. For this reason, it was not possible to increase the heat transfer rate by increasing the acid supply rate by bottom-blowing agitation using a porous plug.

As a method for solving the above problem, FIG.
As shown in FIG. 7, an inert gas is blown into a molten steel 32 in a ladle 31 by a bubbling lance 33 to stir the molten steel 32, and a snorkel 34 is immersed in the slag 35.
, A heating agent is added to the molten steel bath surface in the snorkel 34, and oxygen blowing is performed by an upper blowing lance 36. For example, in a method of heating a molten steel in a ladle by adding an exothermic agent to molten steel housed in a ladle and blowing oxygen gas while blowing inert gas to stir the molten steel, the molten steel was deeply immersed in the molten steel in the ladle. The molten steel is stirred by blowing an inert gas with a bubbling lance, and a snorkel having a smaller diameter than the molten steel bath surface exposed by the plume generated at that time is immersed to cut slag, and then heat is generated in the molten steel bath surface in the snorkel. A method in which an oxygen blowing agent is added and oxygen blowing is performed using an upper blowing lance (Japanese Patent Application Laid-Open No. 64-56816), a method in which a snorkel is immersed in molten steel in a ladle and gas is agitated by a immersion lance. And a snorkel with a double cylindrical structure, the inner cylinder of which is shorter than the outer cylinder.When the molten steel is heated, the inner and outer cylinders of the snorkel are immersed in the molten steel to cut off the slag in the inner cylinder. Oxygen gas is blown from the upper blowing lance to the molten steel bath surface, and the snorkel is raised during desulfurization to cover the molten steel bath surface with the lower end of the inner cylinder away from the bath surface. ,
A method of refining while the outer cylinder is immersed in molten steel (JP-A-64-65226). A molten metal is charged into a ladle and a snorkel having an opening at the lower end is placed in the molten metal. While immersing and further reducing the pressure inside the snorkel, a gas is blown into the molten metal from near the lower end of the snorkel or from a position below the lower end, and the gas floats in the molten metal in the snorkel and melts. There is a method of stirring and refluxing a metal (JP-A-3-6317).

The above-mentioned JP-A-64-56816, JP-A-64-65226, and JP-A-3-6317.
The method of using a snorkel disclosed in Japanese Patent Application Publication No. H10-27146 can solve the problem of bottom-blowing agitation by the porous plug.However, when the snorkel is immersed in molten steel and agitated, the molten steel is scattered and the ingot of the metal is formed on the inner surface of the snorkel. Adhesion occurs, which hinders processing, and has the disadvantage of requiring snorkel repair. As shown in FIG. 4 and FIG. 5, as a method for repairing the snorkel after the ladle refining process, the snorkel 34 is removed from the ladle refining apparatus, and then the snorkel 34 is placed on the repair work table 37 and the carolose pipe is removed. 3 using a jet lance 38, etc.
4. Oxygen is blown onto the metal 39 attached to the inner surface to dissolve and remove the metal.

[0005]

The method of dissolving and removing the ingot by spraying oxygen onto the ingot attached to the inner surface of the snorkel using the above-mentioned caro rice pipe, jet lance, etc. is about 2 to 4 hours. Not only is required, but also it is difficult to completely remove the metal that has adhered to the inner surface.

An object of the present invention is to provide a ladle refining snorkel that can quickly and completely remove metal adhered to the inner surface of a snorkel after a ladle refining process.

[0007]

Means for Solving the Problems The present inventors conducted various tests and studies to achieve the above object. As a result, the ladle refining snorkel inner surface is provided with a taper in the metal adhesion portion,
After coating the tapered portion with an easily peelable spraying material, the tapered portion is restored with a silica board, asbestos, rock wool, a wire mesh, or the like, so that the metal adhered to the inner surface of the snorkel is easily peeled off. It has been confirmed that the material can be easily peeled off from the sprayed material, and the present invention has been achieved.

That is, in the present invention, the molten steel is stirred by blowing an inert gas with a bubbling lance deeply immersed in the molten steel in the ladle, an exothermic agent is added to the molten steel bath surface, and oxygen blowing is performed by the upper blowing lance. In the snorkel used for slag cutting at the time of performing, after providing a taper in the base metal attached portion on the inner surface of the snorkel, coating the tapered portion with a spraying material that is easily peelable, silica board, asbestos, rock wool,
A ladle refining snorkel characterized by having a tapered portion restored with a wire mesh or the like.

[0009]

In the present invention, a taper is provided on a portion of the inner surface of the snorkel where the metal is adhered, and the tapered portion is coated with an easily peelable spraying material.
Since the tapered portion was restored with rock wool, a wire mesh, or the like, when the steel plate was immersed in the molten steel in the ladle to perform the ladle refining process, the scattered metal adhered to the restored tapered portion on the inner surface of the snorkel. Therefore, the ingot that has adhered to the restored tapered portion easily peels off from the easily peelable spray material portion, and the ingot that has adhered can be completely removed in a short time. In addition, the snorkel from which the adhered metal has been removed can be reused by coating the tapered portion again with an easily peelable spraying material, and then restoring the tapered portion with a silica board, asbestos, rock wool, wire mesh, or the like. Repair work can be greatly reduced.

[0010] To remove the sliver attached to the tapered portion on the inner surface of the snorkel, remove the snorkel from the ladle refining device, and use a separately provided inner slab removal tool to remove the shard from the tapered portion. After peeling from the part, the sliver is removed by a crane on the repair work bench.
After removing the ingot, recoat the tapered part on the repair work bench again with a sprayable spraying material, then restore the tapered part with silica board, asbestos, rock wool, wire mesh, etc., and reuse it Can be offered. As the easily peelable spraying material used in the present invention, a silica-based spraying material is suitable. The wire mesh used for restoring the taper on the coating of the easy-to-peel spray material is for reinforcement.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 The details of the present invention will be described below with reference to FIGS. FIG. 1 is a side sectional view of the ladle refining snorkel of the present invention, FIG. 2 is an enlarged cross-sectional view of the restored tapered portion of the ladle refining snorkel of the present invention, and FIG. (A) is a side cross-sectional view when the adhered slab is peeled off by the slab removing tool, and (b) is a side cross-sectional view when the adhered slab is removed on the repair work table. 1 and 2, 1 is a snorkel body for ladle refining,
Reference numeral 2 denotes a taper provided on the base metal attachment portion of the snorkel main body 1. The tapered portion is coated with a silica-based easy-to-peel spraying material 3, and then restored by a wire mesh 4 and a heat-resistant castable 5, and the molten steel in the ladle is removed. When the smelting process is performed by immersing the metal in the ladle, the scattered metal is attached to the restoration portion 6 on the inner surface of the snorkel main body 1.

With the above construction, when the snorkel of the present invention is immersed in molten steel in a ladle (not shown) and subjected to ladle refining processing, the scattered metal adheres to the restoration portion 6 on the inner surface of the snorkel main body 1. Therefore, the adhered metal 7 can be easily peeled off from the easy-to-peel spraying material 3 of the restoring section 6, and the adhered metal 7 can be completely removed in a short time. As shown in FIG. 3, the attached metal 7 is removed by lifting the snorkel body 1 from a ladle refining device (not shown) by using a crane 11 or the like, and inserting the snorkel body 1 into the projection 13 of the metal removal tool 12. Then, the projection 13 comes into contact with the lower end of the adhered metal 7, and the adhered metal 7 is separated from the easily peelable spray material 3 portion of the restoration unit 6. Next, the snorkel main body 1 is placed on the repair work table 14, and the adhered metal 7 that has been peeled off from the easily peelable spray material 3 of the restoring section 6 is lifted off by a crane 15 or the like. Further, the snorkel body 1 from which the adhered metal 7 has been removed can be reused by coating the tapered portion again with the easily peelable spray material 3 and then restoring and repairing the tapered portion with the wire mesh 4 and the heat-resistant castable 5. Repair work for the main body 1 can be greatly reduced.

Example 2 C melted in a 160 Ton converter: 0.02 to 1.00%
After the molten steel was processed by the ladle refining device using the snorkel of the present invention of the first embodiment, the snorkel body was removed from the ladle refining device, and the deposited metal was easily peeled off by using a metal removal tool. Peel off from the spraying material part, remove the adhered flakes from the easy-to-peel spraying material part on the repair work table, coat the tapered part again with the easy-to-peeling spraying material, and then use a wire mesh and heat-resistant castable. When the tapered portion was repaired and repaired, the time required to remove and repair the adhered metal was reduced by 1 / compared to the case where a conventional snorkel was used to remove and repair the adhered metal by the method of removing metal as shown in FIG.
2, and the adhered metal could be completely removed.

[0014]

[Effects of the Invention] As described above, the snorkel for ladle refining of the present invention requires one time for removing and repairing adhered metal.
/ 2 as well as completely removing the ingot that has adhered to the inner surface of the snorkel.

[Brief description of the drawings]

FIG. 1 is a side sectional view of a ladle refining snorkel of the present invention.

FIG. 2 is an enlarged cross-sectional view of the restored tapered portion of the ladle refining snorkel of the present invention.

FIG. 3 shows the situation of removal of the deposited metal of the present invention.
(A) is a side sectional view at the time of peeling of the adhered slab with the slab removing tool, and (b) is a side sectional view at the time of removing the adhered slab on the repair work table.

FIG. 4 is a side sectional view of a conventional ladle refining snorkel.

FIG. 5 is a side sectional view showing a conventional state of removing adhered metal.

FIG. 6 is a side sectional view of a ladle refining apparatus using a snorkel.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 Snorkel main body 2 Taper 3 Easy-to-peel spraying material 4 Wire mesh 5 Heat-resistant castable 6 Restoring part 7 Bonded slab 11, 15 Crane 12 Slab removing tool 13 Projection part 14, 37 Repair work table 31 Ladle 32 Molten steel 33 Bubbling lance 34 Snorkel 35 Slug 36 Upper lance 38 Jet lance 39 Bullion

Claims (1)

(57) [Scope of request for utility model registration] 1. An inert gas is blown into a ladle with a bubbling lance deeply immersed in molten steel to stir the molten steel, a heating agent is added to the molten steel bath surface, and oxygen blowing is performed by an upper blowing lance. In the snorkel used for slag cutting, a taper is provided on the base metal attachment portion on the inner surface of the snorkel, and the tapered portion is coated with an easily peelable spraying material, and then the tapered portion is formed with a silica board, asbestos, rock wool, a wire mesh, or the like. A ladle refining snorkel that has been restored and repaired.