JPH04118158A - Method for repairing submerged nozzle - Google Patents

Abstract

PURPOSE:To drastically improve workability and to save labor of the work by sticking repairing material under plastic condition onto outer peripheral damaged part in a submerged nozzle while holding the repairing material with a covering body surrounding the above outer peripheral damaged part. CONSTITUTION:Onto the outer peripheral damaged part 2b in the submerged nozzle 2, the repairing material 2' under plastic condition is stuck while holding the material 2' with the covering body 1 surrounding the above outer peripheral damaged part. Holding of the repairing material with the covering body is desirable to execute with hanging tool of projections 1c, hook, etc., arranged to the covering body. The repairing material may be used as it is or as the one packed into cloth bag, 'Teflon(R)' bag, plastic bag, vinyl bag, etc. Further, at the time of surrounding the covering body to the outer peripheral damaged part, the repairing material is desirable to pressurize, and by executing such way, the sufficient sticking strength of repairing material can be obtd. By this method, the workability is drastically improved and the repairing not only at the room temp., but also at the high temp. can be executed in a short time.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for repairing a submerged nozzle used in continuous casting.

[Prior art] When injecting molten steel from a tundish into a mold, a submerged nozzle inserts its lower end into the molten steel in the mold in order to prevent the molten steel from oxidizing or dropping in temperature, or to prevent mold powder from getting involved. It is used by dipping, and its outer periphery is usually severely eroded by mold powder, slag, etc. that come into contact with it.

Conventionally, in order to repair damage caused by erosion of mold powder or the like on a submerged nozzle, a repair method has been attempted in which a repair material in a plastic state is directly applied to the damaged outer periphery of the submerged nozzle, which has reached room temperature.

[Problems to be Solved by the Invention] However, in the above-mentioned conventional immersion nozzle repair method, the adhesive strength of the repair material itself is weak, so the repair material may drip or peel off before it adheres to the damaged area. Repairs could not be made.

In particular, in hot repairs, such as repairs at temperatures above 600°C, the applied repair material may burn locally or foam and scatter, resulting in it not adhering and peeling off from one end where it is applied. It was impossible to repair the work, as it only contaminated the area around the work area.

Therefore, an object of the present invention is to provide a method for repairing a submerged nozzle that enables not only repair at room temperature but also repair in hot conditions.

[Means for Solving the Problems] In order to solve the above-mentioned problems, the method for repairing a collapsed nozzle of the present invention includes surrounding the damaged outer periphery of a submerged nozzle with a repair material in a flexible state. This is a method of holding and attaching the material using a covering body.

[Function] In the above means, the wrapping body prevents the repair material from hanging down or peeling off.

It is preferable that the repair material is held by the envelope using a locking device such as a protrusion or a hook provided on the envelope.

The repair material may be used as is, or may be packed in a cloth bag, Teflon bag, plastic bag, plastic bag, or the like.

Further, when enclosing the outer peripheral damaged portion with the envelope, it is preferable to pressurize the repair material, and by doing so, the adhesion strength of the repair material can be made sufficient.

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

Example 1 General structural rolled steel material (JIS G3101, symbol 5S
As shown in Fig. 1, a semi-cylindrical main body 1a has flanges 1b extending inward at both ends, and a large number of V-shaped protrusions on the inside of the main body 1a. A pair of envelopes 1 were manufactured, each having an IC and connecting members 1d made of wires with one end welded to the upper and lower sides of the main bodies 1a in order to connect the main bodies 1a to each other. The inner diameter of the flange 1b of the envelope 1 is the same as that of the immersion nozzle 2 that requires repair.
It is preferable that the outer diameter of the nozzle body 2a (see FIG. 2) be appropriately larger.

On the other hand, ZrO265% by weight, C15% by weight, 5iC15
% by weight, for 100 parts by weight of mixed raw materials containing 5% by weight of Si,
Repair material 2 was prepared by adding and mixing 15 parts by weight of sodium silicate solution.
' (see FIG. 2) was prepared and loaded inside each envelope 1 to obtain a repaired body. The repair material 2' was loaded into the envelope 1 by protruding it from the flange 1b as appropriate so as to fill the damaged area 2b of the immersion nozzle 2 on the outer periphery (see FIG. 2).

Then, as shown in FIG.
00°C or higher) is applied to the outer peripheral damaged part 2b of the immersion nozzle 2 so as to surround it, and the main bodies 18 are fastened together using the connecting tool 1d, and the repair material a protruding from the gap between the flange 1b and the nozzle main body 2a, etc. ′ was scraped off and repaired.

In FIG. 2, 2C is a nozzle hole, and 2d is a discharge port.

In the repaired immersion nozzle, the repair material was fired during subsequent use and became integrated with the nozzle body 2a, and there was no problem in use.

Example 2 Exband metal (JIS G3351. Symbol XS
, product number 31), and as shown in Fig. 3, bend the - side and insert the bent part 3, which will serve as a retaining allowance for the repair material to be described later.
8, and also had protrusions (not shown) formed by cutting the mesh at required locations and bending them inward.

On the other hand, as in Example 1, a mixed raw material 10 containing 65% by weight of ZrO2, 15% by weight of C, 15% by weight of 5iC, and 5% by weight of Si was prepared.
A repair material was prepared by adding and mixing 15 parts by weight of a sodium silicate solution to 0 parts by weight, and this was packed in a Teflon sheet bag to obtain a bagged repair material 4.

Next, the bagged repair material 4 is locked inside the envelope 3 to form a repair body, and then the repair body is wrapped around the damaged outer periphery of the still-hot immersion nozzle (not shown), and repaired with an appropriate fixing device, for example, a wire. The body was fixed to the nozzle body and the excess repair material was scraped off to repair it.

In this repaired immersion nozzle, as in Example 1, the repair material became integrated with the nozzle body by firing during use, and there was no problem.

In addition, in each of the above embodiments, the case where the envelope 1.3 is approximately the same size as the outer peripheral damaged part 2b of the immersion nozzle 2 has been described, but the present invention is not limited to this, and it is possible to hold the repair material. It may be of any size, and may be larger or smaller than the outer peripheral damaged portion 2b depending on the structure of the envelope 1.3 and the condition of the repair material.

Further, the bag for the bagging repair material 4 is not limited to a Teflon sheet bag, but may be a cloth bag, a plastic bag, a vinyl bag, or other bags.

Furthermore, bagging may be done at the work site or may be done in advance.

[Effects of the Invention] As described above, according to the present invention, the casing prevents the repair material from hanging down or peeling off, so the repair material does not scatter and pollute the workplace as in the past, and work efficiency is improved. It is possible to significantly improve the performance and save labor, and it is also possible to perform not only repairs at room temperature but also hot repairs in a short time and accurately.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing an example of an envelope used in carrying out the method for repairing a submerged nozzle according to the present invention, FIG. 2 is a cross-sectional view of a submerged nozzle hot repaired by the above method, and FIG. 3 is a It is a perspective view showing the other side of the envelope etc. used for carrying out a method. 1... Encapsulation body 1a... Main body 1b...
Flange IC...Protrusion 1d...Connector 2a...Nozzle body 3...Encasing body 4...Bag repair material 2...Immersion nozzle 2b-...Outer periphery damaged part 3a... bending part

Claims (1)

[Claims] (1) A method for repairing an immersed nozzle, which comprises attaching a repair material in a plastic state to the damaged outer periphery of the immersed nozzle while being held by an envelope that surrounds the damaged outer periphery.