JPS61107090A - Method of repairing cooling pipe for furnace body - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention [Industrial Field of Application] The present invention provides a furnace body cooling pipe, for example, a shaft 1 of a blast furnace.
Partly related to methods for repairing cooling pipes of cooling panels, electric furnace cooling plates, etc.

[Conventional technology] For example, when a blast furnace continues to operate for a long period of time,
The furnace wall refractories are eroded, and eventually holes are formed in the cooling pipes that protect the furnace walls, leading to damage.

In this case, as shown in Figure 2, is the cooling pipe buried in the refractory 1 of the furnace wall? There is hole 3! SF+<, cooling water leaks into the furnace from there, making safe operation difficult.The first method is to cut off the cooling pipe 2 at section B, and insert the monolithic refractories 4 into the pipe 2 from both ends. By pouring into the water and covering it with blind plate 5! /.

A method is adopted to destroy the functionality of the cooling pipe 2. 6
is iron skin. The damaged pipe 2 will be replaced with a new pipe at a later date, along with the fireworks on the furnace wall of the same gate, due to long-term repairs.

Alternatively, as shown in Figure 3, as a second method, cooling @7A
, 7B are newly inserted to compensate for the decrease in cooling function. W is cooling water.

Furthermore, Japanese Patent Application Laid-Open No. 58-19416 proposes, as a third method, to repair the damaged portion by spraying a coating material from the inner surface of the cooling pipe. In addition, JP-A-5
Publication No. 7-19309 also proposes, as a fourth method, passing a flexible tube through the damaged pipe and passing cooling water through it.

[Problems to be Solved by the Invention] However, in the first method, there is no cooling effect at all due to the cooling pipe, and in the second method, part A cannot be cooled. Furthermore, using the second method to drill holes in the steel shell and install a cooling plate is not economical and requires a lot of construction work. The third method has low repair reliability, and there is a risk of peeling of the coating material and re-damage.

In the fourth method, since there is a gap between the cooling pipe and the tube, heat conductivity is poor and there is almost no cooling effect.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a repair method that is easy to work with, is economical, and has an excellent cooling effect.

[Means for solving the problem] In order to solve the above-mentioned problem, the present invention inserts a flexible and heat-resistant repair tube into the damaged cooling pipe from outside the furnace body, and leads both ends of the tube to the outside of the furnace body. In this state, a monolithic refractory is press-fitted from outside the furnace body into the gap between the pipe and the tube, and then hardened once, and then cooled by passing water through the tube.

The present invention has some similarities with the fourth method, but differs greatly in that a monolithic refractory is press-fitted into the gap between the pipe and the tube.

[Operation] The purpose of the present invention is to make use of damaged cooling pipes as much as possible. For this purpose, a tube is passed through the damaged cooling pipe and used as a cooling tube for repair. At this time, even if water is poured into the tube as described in method 1-4, there is an air gap between the tube and the cooling pipe.
It has poor heat conductivity and has almost no cooling effect. Therefore, a monolithic refractory with good thermal conductivity is press-fitted into the gap, and the inside of the furnace is efficiently cooled using this refractory as a heat transfer body. Further, since the press-fitted refractory is poured out into the inner surface of the furnace through the damaged hole, it also covers and protects the hole, so that the progression of damage can be prevented.

[Specific Examples of the Invention] The present invention will be further explained in detail below using a specific example shown in FIG.

If a hole 3 is made in the cooling pipe 2, the cooling water supply systems 8A and 8B are separated from each other at part B, and the water in the cooling pipe 2 is drained. Next, a flexible and heat-resistant repair tube 9, such as a thin-walled stainless steel bellows tube, is inserted from the cut end of the cooling pipe 1, and the other end is led out of the furnace body. Subsequently, a blind plate 1O is provided between the cut ends and the repair tube 9.

Thereafter, a refractory M having good thermal conductivity, such as carbon-containing mortar that hardens at a relatively low temperature, is press-fitted into the gap between the cooling pipe 2 and the repair tube 9 through the injection port 11 formed in the cooling pipe 2 . At the time of this press-fitting, a plurality of injection ports ll may be formed as shown in the figure, or one of them may be used as an exhaust port.

Along with the press-fitting, a part of the refractory M is poured out from the hole 3,
Since the damaged brick portion is covered and the hole 3 is closed, the progression of damage is prevented.

If there is a risk of the repair tube 9 being crushed by the pressure during press-fitting, it is preferable to fill the repair tube 9 with a pressure rotating body to counteract the press-fitting pressure. Once the press-fitting is completed, it is possible to wait for the natural hardening of the refractory M, but in order to develop strength early, it is preferable to blow hot air such as exhaust gas from a burner etc. into the repair tube 9.

Thereafter, a water supply pipe 12A and a drain pipe 12B are connected to both ends of the repair tube 9, and cooling water W is passed through the repair tube 9. By this water flow, cooling heat is transferred to the monolithic refractory M.
Heat is transferred to the inner surface of the furnace wall through the heat, protecting the furnace wall. Therefore, the entire refractory 1 is cooled.

[Example 1] Repair was carried out in the manner shown in FIG. 1 and described above. The monolithic refractory used had AkOz: 60 wt%, C:
10%, MgO: 20%, Na, ○(S)
After press-fitting with a mortar containing an iO□)-based binder, hot air was supplied for 3 hours. Subsequently, cooling water was supplied and a repair room was created, and after a long period of operation, the cooling capacity was almost the same as before the damage, and there was no new damage.

[Effect of the invention 1 As described in 1-1 below, according to the present invention, cooling can be performed over the same area as before damage, and the cooling performance is excellent.
Furthermore, enforcement becomes easier. moreover.

The monolithic refractory fills the damaged part and prevents the damage from progressing.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view of an embodiment of the method of the present invention f; FIGS. 2 and 3 are longitudinal sectional views of a conventional example. 1. Refractory 2. Cooling pipe 3
,,,,Damaged hole 6,,,,Steel skin 9,,,
, Repair tube 11 , , , Worker M , , Monolithic refractory W , Cooling water patent applicant Sumitomo Metal Industries, Ltd. 1 Figure 1

Claims (1)

[Claims] (1) Insert a flexible, heat-resistant repair tube into the damaged cooling pipe from outside the furnace body, and with both ends led out of the furnace body, insert a monolithic refractory into the gap between the pipe and the tube from outside the furnace body. A method for repairing a furnace cooling pipe, which comprises press-filling, hardening, and cooling by passing water through the tube.