JPH065397Y2 - Stave cooler - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a stave cooler used for cooling a furnace wall of a blast furnace.

[Conventional technology]

For example, in order to cool the furnace wall of the blast furnace, a stave cooler is placed between the iron shell and the refractory brick, and the cooling water is caused to flow through the cooling water pipe that has been cast into the stave cooler. It is prevented from being transmitted. This stave cooler is attached, for example, by the method described in Japanese Utility Model Publication No. 55-13960.

The conventional stave cooler has a structure as shown in FIG. That is, the protection pipe 2 is inserted into the cooling water pipe 1 and is cast around the stave cooler body 3. The stave cooler body 3 is arranged between the furnace inner wall 4 and the iron shell 5 which are constructed of refractory bricks or the like. At this time, the irregular refractory 6 is filled between the stave cooler body 3 and the iron shell 5, and the stave cooler body 3 is fixed to the iron sheath 5 by the bolts 7 via the irregular refractory 6.

As the irregular refractory material 6, castable refractory materials are generally used. The irregular refractory 6 is hardened within a few days after being filled between the stave cooler body 3 and the iron skin 5. Even if the stave cooler body 3 is heated by the high heat inside the furnace, the heat insulation prevents the heat from being transmitted to the iron shell 5. Further, the protection pipe 2 prevents an accident such as water leakage due to the cooling water pipe 1 coming into direct contact with other members.

[Problems to be solved by the device]

As shown in FIG. 4, the protective tube 2 has a base end portion 2a that is cast around the stave cooler body 3 and is shaped like a bosh.
It is designed so that the protective tube 2 does not fall out of the stave cooler body 3 when axial pulling and bending forces are applied to the. In order to form this morning glory-like base end portion 2a, the conventional protection tube 2 is formed thinner toward the base end side. A hot water retaining ring 8 is interposed between the protection pipe 2 and the cooling water pipe 1, and the cast iron forming the stave cooler main body 3 is cast and integrated.

However, during this casting, the protection tube 2 is not completely fused to the stave cooler body 3, and breakage inside the stave cooler body 3 or embrittlement due to carburization occurs. Then, when the stave cooler is used while being mounted in the blast furnace, the stave cooler body 3 is thermally expanded by the high temperature gas in the furnace, and the protective tube 2 is stressed. At this time, the protection tube 2
In some cases, the embrittled portion generated during casting becomes a starting point of crack generation and may not withstand external force up to the strength of the base material and may fall off with a force equal to or lower than the strength of the base material. As a result, problems such as damage to the cooling water pipe 1 and water leakage occur.

Therefore, according to the present invention, the stave cooler main body and the protective pipe are mechanically protected by keeping the base end of the protective pipe cast around the stave cooler main body thick and applying a coating for preventing carburization. It is an object of the present invention to provide a stave cooler having excellent durability, suppressing carburizing and brittleness, and having excellent durability.

[Means for Solving the Problems]

In order to achieve the object, the stave cooler of the present invention comprises a cooling water pipe encased in the stave cooler body and a protective pipe surrounding the cooling water pipe and encircled in the stave cooler body. It is characterized in that the base end portion of the protective tube cast around the stave cooler body has the same thickness as the portion protruding from the stave cooler body, and is coated to prevent carburization.

Here, the base end portion of the protective tube may be formed in a morning glory shape. Alternatively, it is also possible to form a base end portion in which a flange is attached to the pipe wall extending in the pipe axial direction of the protective pipe, and the flange is arranged radially outward.

[Action]

In this stave cooler, the protection tube is fixed to the stave cooler body by mechanical entanglement, not by metallurgical connection. Then, in order to have sufficient strength for mechanical entanglement, the base end portion of the protective tube embedded in the stave cooler body is made thicker than the conventional one. Further, a coating for preventing carburization is applied to the base end portion of the protective tube so that a reaction such as carburization does not occur with the cast iron forming the stave cooler body. This allows
The protection tube is prevented from breaking and falling off, and it becomes a stave cooler with excellent durability. Incidentally, as the carburizing inhibitor used here, marshallite (SiO ₂ ), zircon (ZrO ₂ ),
There are silicon carbide (SiC) and the like.

〔Example〕

Hereinafter, the features of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 shows a stave cooler according to the present invention. In FIG. 1, components corresponding to the members shown in FIG. 3 are designated by the same reference numerals, and the description thereof is omitted.

Base end of protective tube 2 that is cast around stave cooler body 3
2a has the same wall thickness (6 mm) as the portion protruding from the stave cooler body 3 and is shaped like a bosh. Then, silica flour kneaded with water glass was sprayed onto the base end 2a, and a ceramic coating 9 having a thickness of 0.5 mm was applied. After fitting this protection pipe 2 into the cooling water pipe 1 and incorporating it into a mold made of foundry sand, approximately 12
Inject molten cast iron at 50 ℃.

In this way, the protective tube 2 cast around the stave cooler main body 3 withstands a force of 90% or more against an axial tensile load of 34 tons of the base material strength of the protective tube, and breaks, drops, etc. The defect did not occur.

On the other hand, as shown in FIG. 4, when the protective tube 2 thinned toward the base end side is cast around the stave cooler main body 3 as it is, the protective tube has a base material strength of 40%. When the force of% was applied, it fell off the stave cooler body 3 at the root part.

FIG. 2 is a diagram for explaining the second embodiment. In the case of the present embodiment, the tube wall of the protection tube 2 is straightened in the tube axis direction, and the flange 10 is attached near the tip of the stave cooler body 3 side. As in the case of FIG. 1, a ceramic coating 9 is provided around the protective tube 2 in order to prevent reaction with the cast iron forming the stave cooler body 3 and carburization. A compressible material such as asbestos tape 11 may be provided around the protective tube 2 to reduce stress applied to the protective tube 2 due to thermal deformation of the stave cooler body 3.

Here, since the protective tube 2 is formed with substantially the same wall thickness over its entire length, the strength of the base material is utilized to prevent breakage. Further, when a force outward in the pipe axis direction is applied to the protective tube 2 cast in the stave cooler body 3, the flange 10 serves as an anchor to prevent the protective tube 2 from falling off.

[Effect of device]

As described above, in the present invention, since the ceramic pipe is cast by placing the ceramics coating between the protective pipe and the stave cooler body, when a reaction that causes a material change such as carburization occurs during the spinning process. It does not occur in protective tubes. Further, since the base end side of the protective tube has a sufficient thickness, the strength of the base material is utilized, and defects such as breakage and falling are prevented. Thus, according to the present invention, a durable stave cooler can be obtained.

[Brief description of drawings]

FIG. 1 shows a stave cooler according to a first embodiment of the present invention, and FIG. 2 shows a stave cooler according to a second embodiment of the present invention. On the other hand, FIG. 3 and FIG. 4 are diagrams for explaining a conventional stave cooler and its problems, respectively. 1: Cooling water pipe, 2: Protective pipe 2a: Proximal end of protective pipe, 3: Stave cooler body 4: Inner wall of furnace 5, Iron shell 6: Unshaped refractory, 7: Bolt 8: Hot water retaining ring 9: Ceramics coating 10: Flange, 11 ... Asbestos tape

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Creator Takahiro Hiroyuki 59, 46 Nakahara, Tobata-ku, Kitakyushu, Fukuoka 59 59 Nippon Steel Co., Ltd. Machinery & Plant Division (72) Inventor Masaaki Morotomi Kitakyushu, Fukuoka 59 Nittetsu Plant Design Co., Ltd., 46 Nakahara, Tobata-ku, Yokohama

Claims (2)

[Scope of utility model registration request] 1. A protection tube which is provided in a stave cooler body, comprising a cooling water pipe cast in the stave cooler body, and a protection tube which surrounds the cooling water pipe and is cast in the stave cooler body. The stave cooler is characterized in that the base end portion thereof has a thickness similar to that of the portion projecting from the stave cooler body and is shaped like a bosh, and is coated to prevent carburization. 2. A protective pipe that is provided in a stave cooler body, comprising a cooling water pipe that is cast in the stave cooler body, and a protective pipe that surrounds the cooling water pipe and that is cast in the stave cooler body. Is equipped with a base end portion in which a flange is attached to a pipe wall extending in the pipe axial direction outward in the radial direction,
A stave cooler characterized in that the base end is coated to prevent carburization.