JPS6010089B2 - How to repair heating furnace skid metal - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a skid metal (
This relates to a method for repairing continuous type skid buttons to continuous type skid rails in a heating furnace.

Because skid metal is exposed to the high-temperature atmosphere inside the heating furnace and comes into contact with the heated material, it is common to install an expensive heat-resistant alloy member by welding it to the skid pipe. The lifespan is extremely short compared to external heat-resistant material coatings. In particular, the high-temperature section inside the heating furnace wears out quickly and needs to be replaced and repaired frequently.

To replace and repair worn skid metal, it is common to remove the skid metal from the skid pipe at the welded part and replace it with a new skid metal, but it is difficult to remove it at the L weld, so it is difficult to replace it. Heat treatment is required to remove residual stress formed by welding heat.
This is difficult to implement in a narrow furnace. Therefore, a skid beam with worn skid metal is taken out of the furnace for a predetermined length (several meters), the skid metal is replaced over a long period of time, and then heat treatment is performed.

However, this method tends to leave defects in the skid pipe during removal and installation, so the entire skid pipe taken out of the furnace is replaced with a new one, It is uneconomical because it wastes manufactured skid metal, skid pipe, and coated refractory materials.

In this way, with conventional methods, it is difficult to repair only the worn skid metal part inside the heating furnace, so repairs are extensive because the long skid beam must be taken out of the furnace, thereby avoiding long-term interruptions in operation. This reduces productivity.

The present invention was developed in view of the above situation, and its gist is that in the repair of skid metal in a power-o-thermal furnace, it is necessary to repair the damaged skid metal at a position away from the welded part of the worn skid metal and the skid pipe in the heating furnace. This method of repairing a heating furnace skid metal is characterized in that after cutting the worn skid metal from the middle, a new skid metal member is added by a welding process.

In the present invention, in order to prevent welding heat from being transmitted to the skid pipe during repair as much as possible and to reduce port contact residual stress due to thermal distortion, the worn skid metal can be cut even at a location away from the welded area between the skid pipe and the worn skid metal. After that, a new skid metal member made of the same material with the height adjusted is welded to the cut location.

By doing this, only the worn skid metal inside the furnace can be repaired in a short time without having to remove the largest skid beam as in the past, which shortens the construction period and contributes to improved productivity.

Next, the present invention will be explained with reference to drawings of embodiments. Figure 8 shows a new skid beam.

This skid beam...well, even in the well-known skid button type, the koto is the skid button, the Akira is the skid pipe, and the turtle is the coated refractory. Supports heated steel materials (slabs, etc.).

The skid beam army is also appropriately supported by supports (not shown). Depending on the furnace capacity of the skid button chick heating furnace shown in this example, ``Usually hundreds to 1,000 or more are used ~ Various heat-resistant alloys are used depending on the temperature conditions of each zone of preheating and scorching heat in the furnace. .

As this skid button honey is used for a long time, it wears out as shown by the broken line 5 in FIG.

FIG. 2 shows a skit beam repaired in a furnace using the repair method of the present invention.

To explain the construction order, first remove the upper half of the fireproof Isogiri 4, then attach the skid button from the skid pipe 3 to the welded part of the skid button at a predetermined distance.
A hole was drilled at a distance of 2Q to 3 sections apart, and the plasma arc was drawn out and cut in a short period of time.After that, the skid button 2j with its groove adjusted was added by welding.

The fireproof covering was then restored and construction completed. This construction was carried out with the Inada water still flowing through the skid pipe 3 inside the furnace.

Even after welding, there was no problem with the operation even though the moat was started without locking the moat. In this way, according to the present invention, only the skid metal that is worn out inside the heating furnace can be repaired in a short period of time. This has the effect of reducing waste compared to removing the pile and repairing the outside of the furnace or replacing it with a new one.

[Brief explanation of drawings]

FIG. 9 is a partially cross-sectional perspective view for explaining the structure of a skid beam. FIG. 9 is a partially cross-sectional perspective view of a skid beam repaired by the method of the present invention. Ryu side cape skid beam "grave... skid metal and Tosen side skid pipe (skid button t turtle side... coated refractories also rumored... welded parts included... scream cutting position calendar 8, f, and 2)

Claims (1)

[Claims] 1. In the repair of heating furnace skid metal, the worn skid metal is cut in the middle at a position away from the weld between the skid metal and the skid pipe in the heating furnace, and then a new skid metal member is added by welding. Repair method.