JPH01162709A - Method for changing stave cooler in blast furnace - Google Patents

Abstract

PURPOSE:To accurately fit a stave cooler at the prescribed position by arranging hole having larger diameter than bolt for fitting the cooler at furnace wall at the time of changing the stave cooler in a blast furnace and inserting the fitting bolt for fitting a sleeve of new cooler hanging down form the furnace opening part from outside into the above hole. CONSTITUTION:At the time of changing to the new stave cooler because of breakage of the stave cooler for cooling belly part in the blast furnace, after reducing the raw material stock line level below the cooler changing part, the broken cooler is dropped down in the furnace. The penetrated hole 4 for the fitting bolt 3 of the stave cooler 2 is beforehand bored at accurate changing position for the cooler on an iron shell 1. The sleeve 5 is fitted from the outside for the fitting bolt 3 to the new stave cooler 2 for changing and hung down into the furnace from the furnace top part. The cooler 2 is drawn with a wire 7 hung to cooling pipe 6 in the cooler 2 near the iron shell 1 side, and after inserting the sleeve 5 into the penetrated hole 4, the sleeve 5 is taken out and nut 11 is screw-fastened into the bolt 3 and the stave cooler 2 can be accurately fitted at the prescribed position on the iron shell 1.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to a method of replacing a blast furnace stave cooler.

(Prior Art) In a stave cooling type blast furnace, the refractory wall is damaged due to the heat in the furnace and the shadow of the charged raw material during blast furnace operation, and the stave cooler is exposed and damaged.

If the stave cooler is damaged and its cooling capacity is reduced or lost, the temperature of the steel shell to which the stave cooler is attached increases, causing cracks or buckling.

Furthermore, accidents such as gas leakage in the furnace or blowing out of raw materials in the furnace may occur, leading to a shutdown of the operation.

Therefore, if the stave cooler is damaged, it must be replaced, but replacing the fireproof wall or stave cooler after shutting down the blast furnace requires a long period of shutdown and a large amount of money, so it is necessary to replace the stave cooler due to local wear and tear. Large-scale replacement or repair work is disadvantageous in terms of production and cost.

However, conventional stave coolers have been replaced by scraping out the ore and coke remaining in the blast furnace after completely shutting down the blast furnace, and then temporarily erecting scaffolding inside the furnace. This method is carried out during blast furnace renovation work, and has the disadvantage of requiring long-term suspension and large amounts of expense.

Therefore, in recent years, consideration has been given to extending the lifespan of blast furnaces and replacing stave coolers without shutting down the blast furnace.

The method is to reduce the ore stock line to a predetermined height, drop the damaged stave cooler to be replaced into the furnace, and then insert the new stave cooler into the furnace through the manhole at the top of the blast furnace and hang it. After lowering it, it is pulled to the iron skin side and fixed.

(Problem to be solved by the invention) By the way, a large number of stave coolers are installed in the furnace, but the gap between these stave coolers is 30 to 4 mm.
It has 0 fins. This is because if the gap is opened more than necessary, it may cause red heat to occur in the steel shell.

Therefore, the above-mentioned method of loading a new stave cooler into the furnace through the manhole at the top of the furnace, suspending it, pulling it toward the steel shell side, and fixing it, does not require the above-mentioned 3 steps.
It is difficult to adjust the position of the stave cooler so that the gap is between 0 and 401 m.

The present invention provides a method for replacing a blast furnace stave cooler that can solve these problems.

(Means for Solving the Problems) The present invention is a stave cooling type blast furnace, and after reducing the ore stock line to a predetermined position, the stave cooler is charged into the furnace through a manhole at the top of the blast furnace, and then lowered. In the stave cooler replacement method, in which the stave cooler is pulled and fixed to the steel shell side, a through hole with a diameter larger than the diameter of the stave cooler mounting bolt is accurately opened in advance at a predetermined position of the steel shell, and on the other hand, the stave cooler mounting bolt is A sleeve whose distal end has a smaller diameter than the proximal end and whose proximal end has a slightly smaller diameter than the diameter of the through hole is fitted over almost the entire length of the mounting bolt, and in this state the stave cooler is inserted into the furnace. The gist of this method is to load and lower the stave cooler, insert the sleeve together into the previously opened through hole, and then remove the sleeve and attach the stave cooler to the steel shell.

(Function) Since the blast furnace stave cooler replacement method according to the present invention is as described above, the stave cooler can be installed in an accurate position, and the stave cooler installation bolts can be protected.

(Example) The method of the present invention will be explained below based on the accompanying drawings.

In the drawings, reference numeral 1 denotes a steel shell, and through holes 4 for mounting bolts 3 of the stave cooler 2 are accurately opened in advance at predetermined positions on the steel shell 1 where the stave cooler 2 is to be mounted. Furthermore, in the present invention, the diameter of the through hole 4 is made larger than the diameter of the mounting bolt 3.

Therefore, when replacing the stave cooler 2, the sleeve 5 is externally fitted onto the mounting bolt 3 of the stave cooler 2, and the sleeve 5 is inserted into the furnace through a manhole (not disclosed) opened at the top of the blast furnace and suspended. It's coming down.

By the way, the sleeve 5 has a smaller diameter on the distal end side than on the proximal side, and the diameter on the proximal side is slightly smaller than the diameter of the through hole 4, and its length is such that the mounting bolt 3 is exposed from the stave cooler 2. The length of the sleeve is slightly shorter than the total length of the sleeve, and it is fitted onto the mounting bolt 3 using sleeve fixing hardware, which will be described later.

Therefore, the stave cooler 2 is inserted into the furnace through the manhole and suspended, and the stave cooling pipe 6 is connected to the stave cooling pipe 6 by means of a wire 7, which is opened in the steel shell 1 through an opening 8 for mounting the stave cooling pipe 6. If the sleeve 5 is pulled toward the steel shell 1 side, the diameter of the distal end of the sleeve 5 is smaller than that of the proximal end, and the diameter of the proximal end is also slightly smaller than the diameter of the through hole 4, so the mounting bolt can be easily removed. 3 is inserted into the through hole 4 along with the sleeve 5. Then, after removing the sleeve fixing hardware 9 screwed onto the tip of the mounting bolt 3 and removing the sleeve 5 in the same manner, a guide hardware 10 as shown in FIG. 2 is inserted between the mounting bolt 3 and the through hole 4, for example. The stave cooler 2 is attached to the steel shell 1 by screwing the nuts 1) onto the mounting bolts 3.

Note that 12 in FIG. 1 indicates a hanging wire of the stave cooler 2.

By the way, the diameter of the proximal end is φ95mm, and the length is 150v.
g. A sleeve 5 with a distal end diameter of φ75 iris, a length of 2251 mm, and a transition length of 100 mm from the distal end side to the proximal diameter is attached to the mounting bolt 3 using the sleeve fixing hardware 9. The stave cooler 2, which is fitted externally, is charged and suspended through a manhole made at the top of the furnace, and then the stave cooler 2, which is fitted externally, is charged and lowered through a φ1) 0 mm through-hole that has been pre-drilled at a predetermined position (with an error of ±3 mm) in the steel shell 1. After that, remove the sleeve fixing hardware 9 and the sleeve 5, insert the guide hardware 10 shown in FIG. When I installed it on the steel shell 1, the installation accuracy was within ±51.

(Effects of the Invention) As explained above, in the blast furnace stave cooler replacement method according to the present invention, in a stave cooling type blast furnace, after the ore stock line is reduced to a predetermined position, the stave cooler is replaced from the manhole at the top of the blast furnace. In the stave cooler replacement method, which involves charging the steel into the furnace, lowering it, and pulling it toward the steel shell side and fixing it, a through hole with a diameter larger than the diameter of the stave cooler mounting bolt is prepared in advance at a predetermined position of the steel shell. On the other hand, over the mounting bolt of the stave cooler, a sleeve whose distal end side has a smaller diameter than the proximal end side and whose proximal end diameter is slightly smaller than the diameter of the through hole is fitted over approximately the entire length of the mounting bolt,
In this condition, the stave cooler is charged and suspended into the furnace, and the sleeve is inserted into the previously opened through hole.Then, the sleeve is removed and the stave cooler is attached to the steel shell, so the installation position of the stave cooler is It is accurate and protects the stave cooler mounting bolts. Therefore, according to the method of the present invention, even if multiple stave coolers are replaced, there will be no uninstallable locations due to poor installation accuracy, and at the same time, the joint dimensions between stave coolers can be installed within the required dimension range, and the joint dimensions This has extremely great effects, such as completely eliminating red-hot accidents caused by excessive gaps.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of the main part when replacing the product using the method of the present invention, and FIG. 2 is an explanatory diagram of the main part when it is installed using the method of the present invention. 1 is the iron skin, 2 is the stave cooler, 3 is the mounting bolt, 4
is a through hole, and 5 is a sleeve.

Claims (1)

[Claims] (1) In a stave cooling type blast furnace, after the ore stock line has been reduced to a predetermined position, the stave cooler is inserted into the furnace through the manhole at the top of the blast furnace, lowered, and pulled to the steel shell side and fixed. In the alternative method,
A through hole with a diameter larger than the diameter of the stave cooler mounting bolt is prepared in advance at a predetermined position in the steel shell, and the diameter of the stave cooler mounting bolt is smaller on the distal end than on the proximal end. A sleeve whose diameter is slightly smaller than the diameter of the through hole is fitted over approximately the entire length of the mounting bolt, and in this state, the stave cooler is charged and suspended into the furnace, and the sleeve is inserted into the previously opened through hole. A method for replacing a blast furnace stave cooler, which is characterized in that the sleeve is then removed and the stave cooler is attached to the iron shell.