TWI642788B - Cooling plate for furnace body protection - Google Patents

Abstract

An object of the present invention is to provide a cooling plate for furnace body protection as a cooling plate for furnace body protection provided on the inner wall of a furnace body such as a blast furnace, which can reduce the probability of leakage of cooling water, thereby preventing damage to the cooling plate and achieving a long Lifespan. Such a cooling plate for furnace body protection has a structure in which a steel pipe 3 is inserted into a groove 2 provided in the furnace outer surface 1a or the furnace inner surface 1b of a copper cooling plate body 1, and the cooling plate body 1 The groove 2 and the pipe 3 are joined by hard solder 4 to form a cooling plate body cooling water passage in the cooling plate body 1.

Description

Cooling plate for furnace body protection

The present invention relates to a stave for furnace body protection for protecting a furnace wall exposed to a high temperature such as a blast furnace.

Conventionally, in order to protect the furnace body of the blast furnace from being damaged by the heat load in the furnace, a furnace body cooling device (hereinafter referred to as a cooling plate) is used. The cooling plate for furnace body protection is made of cast iron, rolled copper, cast copper, etc., and has a cooling water path in the cooling plate body. In recent years, in order to cope with the high heat load of the blast furnace body, a cooling plate with higher cooling capacity is required, and as a result, the adoption of copper cooling plates with high thermal conductivity has gradually increased.

In such a cooling plate for furnace body protection, the cooling water passage formed in the cooling plate body differs according to the design idea or which material is used. That is, depending on the material, cast iron is generally used to internally cool the steel pipes. For rolled copper, water channels (drill holes) are generally formed by machining. For cast copper, casting is generally used. Form a waterway.

Hereinafter, the cooling plate for furnace body protection including rolled copper will be described. Since the cooling plate for furnace body protection including rolled copper is manufactured by machining, the dimensional accuracy of the water channel is good. There is almost no need to worry about defects such as "nest" during casting, so the number of adoptions is relatively large.

7 (a) and 7 (b) are respectively a front view and a cross-sectional view taken along line A-A showing the structure of an example of a conventional cooling plate for furnace body protection including rolled copper. In the example shown in FIGS. 7 (a) and 7 (b), a plurality of water channels 52 (here, three) are provided in the cooling plate body 51 including rolled copper. Each water channel 52 is formed in the cooling plate body 51 by machining (drilling). The water channel 52 includes: a water channel body 52a penetrating the longitudinal direction of the cooling plate body 51; and a water supply / drainage passage 52b-1 and a water supply / drainage passage 52b-2 for connecting the water supply / drainage piping 53-1 and the water supply / drainage piping 53-2 communicates and is orthogonal to the waterway body 52a. Both ends of the waterway body 52a are sealed by welding the sealing member 54-1 and the sealing member 54-2. In the water supply / drainage passage 52b-1 and the water supply / drainage passage 52b-2, the water supply / drainage piping 53-1 and the water supply / drainage piping 53-2 including steel pipes or copper pipes are fixed by welding, respectively. The cooling plate body 51 is provided with a plurality of bolts (here, four bolts) 55.

As shown in FIG. 8 as an example thereof, the cooling plate for furnace body protection of the above-described structure is fixed to the iron sheet 61 of the blast furnace body by screwing using bolts 55 and nuts 56. The water supply and drainage piping 53-1 and the water supply and drainage piping 53-2 of the cooling plate body 51 penetrate the holes formed in the iron sheet 61 of the blast furnace body to supply and drain water from the outside of the furnace body.

Almost all of the causes of damage to the copper cooling plate due to the repeated thermal load in the blast furnace are water leaks from the cooling system. In recent years, due to the increase in the injection of pulverized coal, the heat load on the furnace body has risen significantly, and the cooling plate breakage occurred at an early stage compared to the life expectancy and expectation in the design stage. Therefore, the water immersion in the furnace caused by the damage of the cooling plate will greatly hinder the stable operation of the blast furnace. Therefore, when water leakage is confirmed during the operation, stop measures for cooling water circulating in the water path of the cooling plate are implemented. As the cooling water stops, the copper cooling plate will be exposed to the high temperature in the furnace and the environment caused by the abrasion of the raw materials, so that the cooling plate body itself will disappear in a short period of time. Due to the disappearance of the copper cooling plate (the disappearance of the cooling function), this time, the iron skin of the blast furnace body will be directly exposed to high temperature, which will cause the iron skin to crack or thermally deform, and the blast furnace operation will continue to be difficult.

The water leakage of the copper cooling plate can be found by mixing the gas in the blast furnace into the cooling water, and the location of the water leakage is estimated as follows based on the investigation results. (1) Deformation caused by high heat load, water leakage caused by cracking at the welded joint of the water supply and drainage water pipe of the cooling plate body and the water supply and drainage pipe; (2) Deformation caused by high heat load, in order to borrow the cooling plate body Water leakage caused by cracks in the welded part of the sealing member used to close the unnecessary opening when the water channel is formed by machining; and (3) The cooling water channel is open due to the wear caused by the raw materials in the furnace due to the low mechanical strength and hardness And caused water leakage. Therefore, for long-term stable operation of the blast furnace, it is necessary to solve the water leakage of the copper cooling plate and to prolong the service life.

In the rolled copper cooling plate, since the cooling water channel is formed in the cooling plate body itself, it has higher cooling capacity than water cooling of the cast piping used in the cast iron cooling plate. However, in the rolled copper cooling plate, the cooling water channel is often damaged due to the damage of the cooling plate body, thereby causing the early disappearance of the cooling plate body. Therefore, the rolled copper cooling plate eventually becomes short-lived. On the other hand, in the cooling plate made of cast iron, the cooling passage includes casting piping and is independent of the cooling plate body. Therefore, the damage of the cooling plate body has little influence on the cooling passage, but in the casting pipe, the heat transfer rate is lowered due to the boundary layer between the pipe and the cooling plate body, so the cooling capacity is not high.

As a solution to the above-mentioned problem, those who seek to prolong the life of copper cooling plates are known to have a structure in which a groove is made by machining or the like on the outside of the furnace of the copper cooling plate, and steel pipes are inserted into the groove. And bolts are used to fix the steel plate (Patent Document 1). Prior Art Literature Patent Literature

Patent Document 1: Japanese Patent Laid-Open No. 2002-146418

[Problems to be Solved by the Invention] However, the copper cooling plate of the structure disclosed in Patent Document 1 has the following disadvantages. That is, the connection between the copper cooling plate and the steel plate for fixing the pipe in the groove is performed by means of bolts, so it cannot be joined to the end of the steel pipe. Therefore, due to the difference in the thermal expansion coefficients of the copper cooling plate and the steel plate (copper: about 1.6 × 10 ^-5 / ° C, iron: about 1.0 × 10 ^-5 / ° C), the steel plate is deformed due to thermal load, and the opening of the steel plate is opened. Then, the raw material intrudes into it, the thermal load rises, and eventually the bolt breaks. As a result, the steel plate is detached from the copper cooling plate, and the function of the cooling plate is also lost while the piping maintenance function is lost. By using steel plates on the outside of the furnace, the cost is suppressed, but at the same time, the cooling capacity of the iron skin and refractory of the blast furnace body also decreases.

An object of the present invention is to provide a cooling plate for furnace body protection as a cooling plate provided on an inner wall of a furnace body or the like, which can reduce the probability of leakage of cooling water, thereby preventing damage to the cooling plate and achieving a long life. [Means to solve the problem]

In order to solve the aforementioned problems associated with the prior art and to achieve the above-mentioned purpose, intensive research was conducted. As a result, the inventors and others finally developed the novel cooling plate for furnace body protection described below. That is, the present invention is a cooling plate for furnace body protection, which is characterized by having a structure in which a steel pipe is placed in a groove provided on the furnace outer surface or furnace inner surface of a copper cooling plate body, and The groove of the cooling plate body and the piping are joined by hard solder, thereby forming a cooling water path for the cooling plate body in the cooling plate body.

In addition, in the cooling plate for furnace body protection of the present invention configured as described above, the following structure may be considered as a better solution, namely: (1) The groove is covered by welding The hard solder is formed with a cover; (2) At one end and the other end of the piping, a piping inlet and a piping outlet are integrally formed with the piping, the piping inlet and the piping outlet are When the piping is installed in the groove, it protrudes from the outer surface of the furnace of the cooling plate body; (3) A protection pipe is provided on the outer periphery of the piping inlet and piping outlet; (4) In the groove A first intermediate member is provided between the surface and the hard solder; and (5) A second intermediate member is provided between the hard solder and the outer surface of the pipe. [Effect of invention]

According to the cooling plate for furnace body protection of the present invention, for example, the cooling water for a copper cooling plate body such as rolled copper is composed of steel piping, and the copper cooling plate body and piping are joined and embedded with hard solder, thereby obtaining A cooling plate that can withstand high heat loads and has a long life. Moreover, even if the cooling plate body is deformed, the welded portion does not directly contact the water channel, so there is no need to worry about water leakage from the welded portion used in each part of the conventional water channel. Furthermore, by filling the gap between the cooling plate body and the cooling pipe with hard solder, the cooling capacity of the cooling plate body can be improved.

1 (a) to 1 (d) are respectively a front view, a rear view, a cross-sectional view taken along line A-A and a cross-sectional view taken along line B-B showing an example of the structure of an example of the cooling plate for furnace body protection of the present invention. An example of the cooling plate for furnace body protection of the present invention shown in FIGS. 1 (a) to 1 (d) has the following structure: As shown in FIGS. 1 (a) and 1 (b), it is made of copper In the groove 2 (here three) formed on the furnace outer surface 1a of the cooling plate body 1, the steel piping 3 is inserted as shown in FIG. 1 (c) and FIG. 1 (d), and the cooling plate The groove 2 of the main body 1 and the piping 3 are joined by hard solder 4, thereby forming a cooling water passage for cooling the main body of the cooling plate including the piping 3 in the cooling plate main body 1.

In addition, in another example of the cooling plate for furnace body protection of the present invention shown in FIGS. 2 (a) to 2 (d), it may have the following structure: As shown in FIGS. 2 (a) and 2 (b) As shown in the figure, a groove 2 (here three) is provided on the furnace inner surface 1b of the copper cooling plate body 1, and further, a pipe outlet hole 7-1 and an outlet hole 7-2 are provided on the furnace outer surface 1a, in which As shown in FIG. 2 (c) and FIG. 2 (d), the steel piping 3 is installed, and the groove 2 of the cooling plate body 1 and the piping 3 are joined by hard solder 4 to form in the cooling plate body 1 Cooling plate body including piping 3 is used for cooling water passage.

FIGS. 3 (a) to 3 (c) are steps along FIGS. 1 (a) and 1 (b) for explaining each step in an example of the manufacturing method of the cooling plate for furnace body protection of the present invention. AA line diagram. An example of the manufacturing method of the cooling plate for furnace body protection of the present invention will be described with reference to FIGS. 3 (a) to 3 (c). First, as shown in FIG. The cooling plate body 1 made of copper and the piping 3 made of steel. The groove 2 can be formed by machining the furnace outer surface 1 a of the copper cooling plate body 1 using an end mill or the like. The cross-sectional shape of the groove 2 may be a U-shape, but any shape may be used as long as it can fit into the pipe 3. For the steel pipe 3, a pipe inlet 3-1 and a pipe outlet 3-2 are formed integrally with the pipe 3 at one end and the other end of the pipe 3, and the pipe inlet 3-1 and the pipe outlet 3- 2 When the piping 3 is installed in the tank 2, it protrudes from the furnace outer surface 1a of the cooling plate body 1. The pipe inlet portion 3-1 and the pipe outlet portion 3-2 can be formed by bending the both ends of the pipe 3 of one structure using a bending machine or the like. In addition, for the pipe inlet 3-1 and the pipe outlet 3-2, protective pipes (not shown) may be provided around them.

Next, as shown in FIG. 3 (b), the piping 3 is inserted into the tank 2 such that the piping inlet portion 3-1 and the piping outlet portion 3-2 protrude from the furnace outer surface 1a. Then, as shown in FIG. 3 (c), the hard solder 4 heated to a predetermined temperature to be molten flows into the groove 2 of the cooling plate body 1 and the piping 3, and then cooled to solidify the hard solder 4. Thereby, as the cooling plate for furnace body protection of the present invention, the following structure can be obtained: the groove 2 of the cooling plate body 1 and the piping 3 are joined by the brazing material 4 to form the cooling plate body 1 including the cooling plate The water path of the piping 3 for body cooling.

Furthermore, as another example, FIGS. 4 (a) to 4 (c) are respectively along the steps of FIG. 2 (a) for explaining each step in the manufacturing method of another example of the cooling plate for furnace body protection of the present invention. And the diagram of line AA in FIG. 2 (b). A method for manufacturing another example of the cooling plate for furnace body protection of the present invention will be described with reference to FIGS. 4 (a) to 4 (c). First, as shown in FIG. 4 (a), a copper cooling plate body 1 and steel are prepared The pipe 3 made of copper is formed with grooves 2 on the furnace inner surface 1b, and the furnace outer surface 1a is formed with a pipe inlet 3-1 and a pipe outlet 3-2 protruding from the furnace outer surface 1a Exit hole 7-1 and exit hole 7-2. The groove 2 can be formed by machining the furnace inner surface 1b of the copper cooling plate body 1 using an end mill or the like. In addition, the outlet hole 7-1 and the outlet hole 7-2 can be formed by performing machining from the bottom of the groove 2 or the furnace outer surface 1a using a drill or the like.

Next, as shown in FIG. 4 (b), the piping 3 protrudes from the furnace outer surface 1a through the outlet hole 7-1 and the outlet hole 7-2 through the pipe inlet 3-1 and the pipe outlet 3-2 Load into slot 2. Then, as shown in FIG. 4 (c), the hard solder 4 heated to a predetermined temperature to become molten flows into the groove 2 of the cooling plate body 1 and the piping 3, and then, the hard solder 4 is cooled to solidify. Thereby, as the cooling plate for furnace body protection of the present invention, the following structure can be obtained: the groove 2 of the cooling plate body 1 and the piping 3 are joined by the brazing material 4 to form the cooling plate body 1 including the cooling plate The water path of the piping 3 for body cooling.

In the cooling plate for furnace body protection of the present invention having the above-mentioned structure, the furnace outer surface 1a or the furnace inner surface 1b of the copper cooling plate body 1 made of rolled copper is dug into a U-shaped groove by machining or the like 2. Put the steel pipe 3 into the U-shaped groove 2. By using copper having a higher thermal conductivity than cast iron as the cooling plate body 1 and using the steel piping 3 to make the cooling water channel independent, it is possible to prevent the cooling plate body from being damaged by the cooling water channel and the like as described above The damage of 1 or the early disappearance of the cooling plate body 1. The U-shaped groove 2 machined on the furnace outer surface 1 a or the furnace inner surface 1 b of the copper cooling plate body 1 serves as a cooling water path for the cooling plate body 1. The steel pipe 3 is previously formed into a predetermined shape (a shape corresponding to the layout of the U-shaped groove 2), and is inserted into the U-shaped groove 2 of the copper cooling plate body 1 in cross section. In the state where the piping 3 is installed, the cooling plate body 1 and the piping 3 are joined by the hard solder 4.

For the temperature of the copper cooling plate body 1 exposed to the actual equipment, the inventors and the like implemented the actual equipment (in the operation of the blast furnace) for a long period of time (10 second interval data, two years) with the cooling water flowing. According to the temperature measurement, it is found that the main body of the cooling plate will only rise up to about 400 ℃. From this, it is thought that as long as the cooling plate body 1 and the piping 3 are joined with a hard solder whose melting temperature is defined as 450 ° C. or higher (BAg specified in Japanese Industrial Standards (JIS) Z 3261, etc.), a copper cooling plate The body 1 and the piping 3 will not be separated, thus completing the present invention. Assuming that the temperature of the cooling plate body 1 reaches 400 ° C. or higher, it is only necessary to consider the state where the cooling water is stopped. The plate body 1 itself disappears due to the thermal load in the furnace and the wear caused by the raw materials. In addition, if the melting temperature of the hard solder is too high, the cooling plate body may be deformed during joining. Therefore, the melting temperature of the hard solder is preferably 450 ° C. or higher and 1083 ° C. or lower.

In the cooling plate for furnace body protection of the present invention described above, in Patent Document 1 which discloses a method of holding piping by bolting of a steel plate, the failure of the cooling plate body made of copper and the steel plate cannot prevent Since the problem of piping is maintained, the cooling plate body 1 can be expected to have a longer life. Furthermore, although a gap is formed between the U-shaped groove 2 and the pipe 3, the alloy for "brazing" is flowed into the gap, etc., and the cooling plate body 1 and the pipe 3 are closely joined, so the cooling plate body can be improved The heat transfer rate between 1 and the pipe 3 increases the cooling capacity of the cooling plate body 1 by the water passage including the pipe 3. Moreover, in general, when the piping 3 is welded, a heat-affected portion is locally formed, which may cause the piping 3 to crack and cause water leakage due to the thermal load in use. However, as a feature of brazing, it is not necessary to use the mother The material can be joined by melting, so there is no cracking caused by local heat affected parts. During brazing, although the temperature may be raised to near the phase transition point (approximately 750 ° C) of the steel pipe 3, since it is not melted and is not localized, there is no cracking caused by the heat affected part produce. Furthermore, the hard solder absorbs the difference in thermal expansion between the copper of the cooling plate body and the steel of the piping, and also has the effect of reducing stress concentration.

Furthermore, by adopting the structure as described above, it is possible to eliminate the welded joint between the water supply and discharge inlet and the piping, which is a weak point of the rolled copper cooling plate, which is a cause of water leakage in the past. In addition, the cooling piping is made of steel with a high-temperature hardness higher than copper, and is independent of the copper cooling plate body such as rolled copper, thereby reducing the opening of the cooling path due to thermal deformation or wear of the copper cooling plate body Probability of holes and water leakage. As a result, the cooling capacity of the copper cooling plate of the present invention is higher than that of the conventional cast iron cooling plate, and the damage of the cooling water channel is less than that of the conventional copper cooling plate. Therefore, it is possible to configure a cooling plate for furnace body protection that achieves a longer life.

5 (a) and 5 (b) are cross-sectional views taken along line BB of FIG. 1 (a) and along the diagram, respectively, according to another preferred example structure of the cooling plate for furnace body protection of the present invention. Fig. 2 (a) and Fig. 2 (b) are cross-sectional views taken along the line BB. In the preferred example shown in FIG. 5 (a) in which the groove 2 is provided on the outer surface 1a of the cooling plate body 1, the copper cooling plate body 1 and the piping 3 are joined by hard solder 4, in order to further prevent After falling off, the cover 5 is welded to the U-shaped groove 2, and the end of the cover 5 and the end of the groove 2 of the cooling plate body 1 are joined and attached by the welding portion 6. Furthermore, as in the preferred example shown in FIG. 5 (b), when the groove 2 is provided on the furnace inner surface 1 b of the cooling plate body 1, the cover 5 may be similarly joined by the welding portion 6. The material of the cover 5 is preferably made of the same copper as the main body of the cooling plate, but a cover made of other materials can also be used.

FIGS. 6 (a) and 6 (b) are views showing the structure of still another preferred example of the furnace body protection cooling plate of the present invention as a cross-sectional view taken along line B-B of FIG. 1 (a). In the example shown in FIG. 6 (a), the first intermediate member 6-1 is provided between the surface of the groove 2 and the hard solder 4. Furthermore, in the example shown in FIG. 6 (b), the second intermediate member 6-2 is provided between the hard solder 4 and the outer surface of the pipe 3. As the first intermediate member 6-1 and the second intermediate member 6-2, as long as a material having an appropriate thermal conductivity is used according to the design level of the cooling capacity of the cooling plate, the first intermediate member 6-1 and the piping 3 are installed in the first After the intermediate member 6-1 or the second intermediate member 6-2, brazing can be used for joining. By adjusting the thermal conductivity or thickness of the intermediate member, the cooling capacity of the cooling plate can be adjusted to meet the target. In order to adjust the thermal conductivity of the entire cooling plate and exert the effect of adjusting the cooling capacity, as the intermediate member, a member having at least a thermal conductivity different from any of the cooling plate body 1, piping 3, and hard solder 4 may be used. Furthermore, by adjusting physical properties other than the thermal conductivity of the intermediate member, the function of the cooling plate other than the thermal conductivity can also be changed. In addition, in the preferred examples of FIGS. 6 (a) and 6 (b), the example in which the groove 2 is formed on the furnace outer surface 1 a is described, but in the example in which the groove 2 is formed on the furnace inner surface 1 b, Of course, the effect of the first intermediate member 6-1 or the second intermediate member 6-2 can also be obtained. [Industry availability]

In the cooling plate for furnace body protection of the present invention, the cooling water of the copper cooling plate body is composed of steel pipes, and the copper cooling plate body and the pipes are joined and embedded with hard solder, thereby obtaining high heat load that can also withstand On the other hand, the cooling plate for furnace body protection that has been extended for a long time is an effective method for protecting the inside of the furnace wall exposed to high temperatures in heating furnaces other than the blast furnace.

1. 51‧‧‧cooling plate body

1a‧‧‧Outer surface of furnace

1b‧‧‧Inner surface of furnace

2‧‧‧slot

3‧‧‧Piping

3-1‧‧‧Piping entrance

3-2‧‧‧Pipeline Export Department

4‧‧‧ Hard solder

5‧‧‧ cover

6‧‧‧welding department

6-1‧‧‧The first intermediate member

6-2‧‧‧The second intermediate member

7-1, 7-2‧‧‧‧Exit hole

52‧‧‧Waterway

52a‧‧‧Waterway body

52b-1, 52b-2 ‧‧‧ Water supply and drainage channels

53-1, 53-2‧‧‧ Plumbing for water supply and drainage

54-1, 54-2‧‧‧Sealing member

55‧‧‧bolt

56‧‧‧Nut

61‧‧‧Iron

1 (a) to 1 (d) are respectively a front view, a rear view, a cross-sectional view taken along line A-A and a cross-sectional view taken along line B-B showing an example of the structure of an example of the cooling plate for furnace body protection of the present invention. 2 (a) to 2 (d) are respectively a front view, a rear view, a cross-sectional view along line AA and a cross-sectional view along line BB showing another example of the structure of the cooling plate for furnace body protection of the present invention. . FIGS. 3 (a) to 3 (c) are steps along FIGS. 1 (a) and 1 (b) for explaining each step in an example of the manufacturing method of the cooling plate for furnace body protection of the present invention. AA line diagram. FIGS. 4 (a) to 4 (c) are steps along FIG. 2 (a) and FIG. 2 (b) for explaining each step in another example of the manufacturing method of the cooling plate for furnace body protection of the present invention. AA line diagram. 5 (a) and 5 (b) are cross-sectional views taken along line BB of FIG. 1 (a) and FIG. 1 (b), respectively, taking the structure of another example of the cooling plate for furnace body protection of the present invention, and The figure shown in the cross-sectional view along the line BB of FIGS. 2 (a) and 2 (b). 6 (a) and 6 (b) are cross-sectional views taken along the line BB of FIGS. 1 (a) and 1 (b), respectively, showing another example of the structure of the cooling plate for furnace body protection of the present invention. Figure. 7 (a) and 7 (b) are respectively a front view and a cross-sectional view taken along line A-A showing the structure of an example of a conventional cooling plate for furnace body protection including rolled copper. FIG. 8 is a diagram for explaining an example of attaching the cooling plate for furnace body protection of the present invention to a blast furnace body.

Claims (9)

A cooling plate for furnace body protection is characterized by having the following structure: a steel piping is inserted into a groove provided on the furnace outer surface or furnace inner surface of a copper cooling plate body, and the cooling plate body is inserted The groove and the piping are joined with hard solder to form a cooling plate body cooling water passage in the cooling plate body, and the melting temperature of the hard solder is 450 ° C or more and 1083 ° C or less. The cooling plate for furnace body protection as described in item 1 of the scope of patent application, wherein a cover is formed on the groove so as to cover the hard solder by welding. The cooling plate for furnace body protection according to item 1 of the patent application scope, wherein a pipe inlet and a pipe outlet are formed integrally with the pipe at one end and the other end of the pipe, and the pipe inlet and The pipe outlet part protrudes from the outer surface of the furnace of the cooling plate body when the pipe is installed in the groove. The cooling plate for furnace body protection according to item 2 of the patent application scope, wherein a pipe inlet and a pipe outlet are formed integrally with the pipe at one end and the other end of the pipe, and the pipe inlet and The pipe outlet part protrudes from the outer surface of the furnace of the cooling plate body when the pipe is installed in the groove. The cooling plate for furnace body protection as described in item 3 of the patent application scope, wherein a protection tube is provided on the outer circumference of each of the piping inlet portion and the piping outlet portion. The cooling plate for furnace body protection as described in item 4 of the patent application scope, wherein a protection tube is provided on the outer circumference of each of the piping inlet portion and the piping outlet portion. The cooling plate for furnace body protection according to any one of claims 1 to 6, wherein a first intermediate member is provided between the surface of the groove and the hard solder. The cooling plate for furnace body protection according to any one of claims 1 to 6, wherein a second intermediate member is provided between the hard solder and the outer surface of the piping. The cooling plate for furnace body protection as described in item 7 of the patent application scope, wherein a second intermediate member is provided between the hard solder and the outer surface of the piping.