JP2646177B2 - Thermal spray repair equipment and thermal spray repair method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for repairing a refractory lining of a molten metal processing vessel (including a kiln and a degassing furnace) composed of multiple furnace walls having different inclination angles.

[0002]

2. Description of the Related Art Among molten metal containers, a vacuum degassing furnace, for example, is constituted by multifaceted furnace walls having different inclination angles, and the opening to the outside of the furnace is narrower than the furnace volume. The method of repairing the damaged part of the furnace wall from outside differs depending on the part. The press-fitting repair is performed on the horizontal furnace wall of the lower tank near the opening, and the spray repair is performed on the inner and outer peripheral portions of the immersion pipe.

However, in press-fitting repair, it takes a long time for repair, and the operation is interrupted during that time. In the case of spray repair, frequent repair is required because the construction body has low durability, and repair is hardly performed because the required parts cannot be repaired and the repair effect is low.

[0004] In recent years, thermal spray repair for obtaining a highly durable construction has come into practical use. In thermal spray repair, in particular, the distance between the thermal spray burner and the damaged furnace wall and the spray angle are important conditions for obtaining a highly durable construction body. Therefore, in practical use, as shown in JP-A-3-59390, It is necessary to take measures such as bending the thermal spray burner remotely.

[0005] Fig. 2 shows a conventional thermal spraying operation of, for example, a DH vacuum degassing furnace lined refractory material in a molten metal container composed of multiple furnace walls having different inclination angles.
Damaged portions of the DH degassing furnace can be roughly classified into an inner peripheral portion A of the immersion tube 3 and the reflux tube 4, a lower tank B near the immersion tube 3, and a lower tank laying portion C. In the conventional case, a spraying burner 5 having a bending mechanism (Japanese Patent Laid-Open No. 3-59390) is installed on a lance drive 6 which can be driven up and down and rotatably. It is installed.

The spraying cart 7 is installed on a rail laid below the DH1 so as to be movable left and right, and moves to a position where the spraying burner 5 can be inserted into the DH1 immersion tube 3 during repair. Then, by operating the lance driving device 6, the spraying burner 5 is moved up and down in an upright state and rotated to repair the inner peripheral damaged portion A of the immersion tube 3 and the reflux tube 4.

After repairing the damaged portion A, the thermal spray burner 5 is bent by remote control from outside the furnace, and the thermal spray burner 5 is moved upward and downward by operating the lance driving device 6 to rotate the lower tank side wall portion B. To repair.

However, the repair of the damaged portion C of the lower tank laying cannot be carried out effectively because the distance from the thermal spray burner is too large to obtain a highly durable construction. Therefore, conventional press-fitting repair is applied to the damaged portion C, but the repair takes a long time, and there is a problem that the operation cannot be performed during that time. Also, prepare a spray burner with a different spraying direction,
Although there is a method of replacement, it takes time for replacement, so it is necessary to divide the repair time, and effective repair may not be performed sufficiently.

As described above, it is difficult to perform the thermal spray repair of the entire required repair area with one thermal spray burner, and it has not been possible to obtain a sufficient effect in extending the furnace life and reducing the cost of the furnace material.

[0010]

In the conventional repair of a refractory damaged in a vacuum degassing furnace, it takes a long time to repair a molten metal vessel composed of multiple furnace walls having different inclination angles. Therefore, there were problems such as (1) interrupting the operation, (2) low durability of the construction body, and (3) limited repaired parts, which prevented effective repair. Further, even with a thermal spray repair that can provide a highly durable construction, it is difficult to repair the entire range of the lining refractory with one thermal spray burner.

According to the present invention, the aspect of the repairing part (repairing part position,
It is intended to provide a repairing means which can easily cope with the case where the depth, angle, etc. are various.

[0012]

Means for Solving the Problems A first invention of the present invention is:
A thermal spray repairing apparatus characterized in that a plurality of thermal spray burners having different injection directions of a flame and a powdery refractory material are provided so as to be movable forward and backward and rotatable by respective drive mechanisms.

[0013] The second invention is the first invention,
Spray burners having a plurality of angles and dimensions are prepared as necessary, and can be freely replaced with a spray burner suitable for the mode of the repaired part.

According to a third aspect of the present invention, there is provided a spraying direction suitable for spraying a damaged portion in a case where a multifaceted furnace wall having a different inclination angle is subjected to thermal spray repair using the thermal spraying apparatus of the first and second aspects. A spraying repair method characterized by selecting a spraying burner having the following formulas, sequentially inserting the burner into the furnace, and continuously repairing the damaged portion of the furnace wall by spraying.

[0015]

By using the present invention, it is possible to repair by spraying to obtain a highly durable construction body, and to easily repair the entire range of refractories lining a molten metal vessel composed of multiple furnace walls having different inclination angles. Became. As a result, the interruption of the operation due to the repair and the large-scale repair due to the low durability become unnecessary, the furnace life is extended, and the cost of the furnace material can be reduced.

[0016]

FIG. 1 shows the state of thermal spray repair when the present invention is used for repairing a refractory lining in a DH vacuum degassing furnace. In this thermal spray repair device, a plurality of thermal spray burners 5 and a lance drive 6 are mounted on a thermal spray carriage 7.

At first, the damaged parts A and B are repaired by the thermal spray burner 5 as in the conventional method. At the time of repair, after the thermal spray burner 5 escapes from the furnace, the thermal spray carriage 7 on the rail is moved rightward to a position where the thermal spray burner 9 can be inserted through the inward direction of the immersion tube 3.

Subsequently, the lance driving device 6 is operated to insert the thermal spray burner 5 into the lower tank. The thermal spray burner 9 is set so that the thermal spraying angle with respect to the damaged portion C is set to an appropriate condition for obtaining a highly durable thermal spraying body, and when passing through the immersion pipe 3 and the reflux pipe 4, the thermal spray burner 9 does not interfere with the thermal spray burner 9. To stand upright. The damaged part C is repaired after the spraying burner 9 is bent by remote control in the lower tank.

According to the present invention, a highly durable spray can be applied continuously to all of the damaged portions A, B, and C. Further, other parts can be repaired by mounting a spraying burner with a proper spraying direction on the spraying carriage together with a lance drive. Further, when repairing a portion where the thermal spraying frequency is low, the repair may be performed by replacing the thermal spraying burner with a proper thermal spraying direction without mounting the thermal spraying truck.

[0020]

According to the present invention, of a molten metal vessel having a plurality of furnace walls having different inclination angles, for example, repair of the entire range of a DH vacuum degassing furnace lining refractory can be easily and accurately performed.

That is, in the conventional method, since the proper thermal spraying cannot be performed, the press-fitting repair and the like are performed in parallel. However, according to the present invention, all the damaged portions can be repaired easily. As a result, the repair time was shorter than that of the conventional method, and the productivity was improved. In addition, since the sprayed body can be sprayed under appropriate conditions, the construction body has high durability, and the life of the furnace has been extended, and the cost of the furnace material has been significantly reduced accordingly.
Table 1 shows a comparison table of the furnace life and furnace material cost in the conventional method and the present invention described above.

[Table 1]

[Brief description of the drawings]

FIG. 1 is a schematic explanatory view showing a state of thermal spray repair of DH in an embodiment of the present invention.

FIG. 2 is a schematic explanatory view showing a state of thermal spray repair of DH by a conventional method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 DH 2 Lower tank 3 Immersion pipe 4 Reflux pipe 5 Spray burner (bending type) 6 Lance drive machine 7 Spray trolley 9 Spray burner (spray direction change type) A Damaged part (immersion pipe) B Damaged part (return pipe) C Damage Department (lay)

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Kosuke Yamashita 1-1, Hibata-cho, Tobata-ku, Kitakyushu-shi, Fukuoka Nippon Steel Corporation Yawata Works (56) References U) Tokiko Sho 60-53271 (JP, B2)

Claims (3)

(57) [Claims] 1. A repair of a thermal spraying apparatus comprising a plurality of spraying burners having different injection directions of a flame and a powdery refractory material provided on a bogie so as to be movable forward and backward and rotatable by respective driving mechanisms. apparatus. 2. A thermal spray repairing apparatus according to claim 1, wherein the thermal spray burner has a detachable tip and can be replaced with a thermal spray burner having a desired angle and dimensions. 3. A multi-face furnace wall having a different inclination angle.
Or, when performing thermal spray repair using the thermal spraying device according to claim 2, according to thermal spray repair means of the damaged portion,
A method for repairing a thermal spray, comprising selecting a thermal spray burner having an injection direction suitable for spraying the damaged portion, sequentially inserting the burner into a furnace, and continuously spraying the damaged portion of the furnace wall.