JPH0651790U - Electric arc furnace with a furnace lid steel slag fall prevention tool - Google Patents

Abstract

(57) [Abstract] [Purpose] Thick slag adhered to the boundary between the furnace lid and furnace wall of an arc furnace for melting and refining steel or ferroalloy falls to the outside of the furnace when the furnace lid is swung up and down. The purpose of the present invention is to improve the safety and maintainability by solving the problems that damage the equipment attached to the arc furnace and the equipment in the vicinity of the arc furnace, and that require a large number of man-hours to remove the slag that has fallen and accumulated. In an arc furnace for smelting and refining steel or alloy iron, a plurality of steel slag adhering studs are provided on the upper end surface of the water cooling jacket of the furnace wall of the main body of the arc furnace. With arc furnace.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an arc furnace for smelting and refining steel or ferroalloy, and more specifically, slag that is thickly adhered to the boundary between the furnace lid and the furnace wall falls outside the furnace when the furnace lid is turned up and down and turns. The present invention relates to an arc furnace structure that can improve safety and maintainability by solving problems such as damage to incidental equipment and equipment near the arc furnace, and the problem of requiring a large number of man-hours for removing slag that has fallen and accumulated.

[0002]

[Prior art]

 Except for old-type or small-scale arc furnaces for melting and refining steel or ferroalloys, the arc furnace main body and the arc furnace are used to load raw materials such as scrap into the furnace with good work efficiency. The furnace lid generally has an openable structure. The outer shell of the arc furnace body and furnace lid is made of shaped steel or steel plate, and the inside of the furnace wall and the furnace lid, which are inside the arc furnace body, are lined with refractory bricks or a water cooling jacket to heat the inside of the furnace. Is shut off.

During the melting or refining work, steel slag containing molten steel splash (hereinafter also referred to as slag) is scattered by an arc and adheres to the inside of the furnace wall and the furnace lid. In particular, it adheres thickly to the boundary between the furnace wall and furnace lid. When the furnace lid was opened from the main body of the furnace by the furnace lid elevating and swiveling device for the next process, such as the completion of the melting and refining or melting work, and the charging of raw materials, it adhered thickly to the boundary between the furnace wall and the furnace lid. The slag is attached to the outer periphery of the lower surface of the furnace lid in a suspended manner. When the furnace lid is swung and moved, the vibration causes the slag that was attached in a suspended manner to the outer peripheral portion of the lower surface of the furnace lid to fall out of the main body of the arc furnace. A large number of man-hours are required for cleaning and cleaning the slag that has been damaged or dropped.

The structure of the conventional arc furnace relating to the present invention is shown in FIGS. 3 (a) and 3 (b). A refractory brick or a water cooling jacket 14 is lined inside the arc furnace shell 1 and the furnace lid 2 to shut off the heat in the furnace. However, in recent arc furnaces, a water cooling jacket 14 is used to insulate the inner upper part of the arc furnace 1 (upper part than the upper surface of the molten steel 12) (hereinafter referred to as the furnace wall 13) and the furnace lid 2. There are many examples. The water-cooled jacket 14 is provided with steel slag adhering studs 15 and 17 made of heat-resistant cast steel to facilitate adhering the slag 16 scattered by the arc to a certain extent during the melting or refining work. Utilizing the heat insulation effect of itself, it helps prevent wear of the water cooling jacket.

That is, as shown in FIGS. 3 (a) and 3 (b), a prismatic steel slag adhering stud 15 is provided on the side surface of the water cooling jacket 14 of the furnace wall 13 on the lower surface of the water cooling jacket 14 of the furnace lid 2. Are provided with chin-shaped steel slag adhering studs 17 scattered all over the furnace wall 13 and the water cooling jacket 14 of the furnace lid 2.

However, when the furnace lid 2 is moved in the XY direction shown in FIG. 3 (b) by the furnace lid elevating and swiveling device to finish the melting and refining or the melting work and to charge the raw materials, the slag 16 is removed. It is icicle-shaped and attached to the outer peripheral portion of the lower surface of the furnace lid 2, and is lifted up. That is, the slag 16 adhered to the boundary between the furnace lid 2 and the furnace wall 13 thicker than other portions does not remain on the furnace wall 13 side but adheres to the furnace lid 2 side and is lifted.

The lifted slag 16 breaks and drops around the location indicated by the broken line A-AA due to the vibration of movement, and the dropped slag 16H damages the arc furnace incidental equipment or equipment near the arc furnace as it is. Also, the falling slag 16H accumulates on the work floor, and a large number of man-hours are required for its removal and cleaning work.

[0008]

[Problems to be solved by the device]

 The slag that is thickly adhered to the boundary between the furnace lid and the wall of the arc furnace that melts or refines iron or steel alloys falls outside the furnace when the furnace lid is swung up and down, and the arc furnace auxiliary equipment or arc It is to improve the safety and maintainability by solving the problem that damages the equipment near the furnace and requires a large number of man-hours to remove and clean the dropped slag.

[0009]

[Means for Solving the Problems]

 Means for solving the problems is to prevent steel slag adhering to the furnace lid from dropping in the arc furnace when the furnace lid of the arc furnace is opened from the main body of the arc furnace. Therefore, a plurality of steel slag adhering studs are provided on the upper end surface of the water cooling jacket of the arc furnace furnace wall.

[0010] The inventors of the present invention, when hoisting the furnace lid as described above, pursue the cause that the slag does not remain on the furnace wall side and adheres to the furnace lid side and is lifted up. The structure of the above-mentioned furnace lid and furnace wall was investigated. However, it was found that the former slag properties could not be changed during melting and refining. Therefore, we mainly conducted investigations and experiments on the latter furnace structure in order to pursue the above causes.

The means for solving the problems of the present invention will be briefly described. When the furnace lid is lifted, the slag should be separated at the boundary between the furnace lid and the furnace wall. Therefore, paying attention to this point, various experiments were conducted on the structure of the furnace lid and the furnace wall, and the conditions for equipping the steel slag adhesion studs, and in particular, the observation of the condition of the steel slag adhesion on the furnace wall was performed in detail. .

As a result, conventionally, as shown in FIG. 3, the upper surface of the furnace bezel and the upper end surface of the water cooling jacket on the upper part of the furnace wall are at the same height, and there is a hindrance when the furnace lid moves up and down. No steel slag adhering studs were provided on the upper end face of the jacket. Therefore, when the slag thickly adhered to the boundary between the furnace wall and the furnace lid is lifted, the slag does not separate at the boundary between the furnace lid and the furnace wall and sticks to the outer periphery of the lower surface of the furnace lid in a suspended manner. It turned out to be.

Therefore, in consideration of positioning the upper end surface of the water cooling jacket below the upper surface of the furnace bezel by a size necessary to have the steel slag adhering studs, as shown in FIG. By adding multiple steel slag adhesion studs to the upper end surface of the wall water cooling jacket, the slag can be reliably separated at the boundary between the furnace lid and the furnace wall when the furnace lid is lifted. It was successfully put to practical use as in the example.

[0014]

[Action]

 In the arc furnace of the present invention configured as described above, a plurality of steel slag adhering studs are additionally provided on the upper end surface of the water cooling jacket of the arc furnace, so that the boundary between the furnace wall and the furnace lid is thickened. As a result of the adhered slag being strongly adhered to the upper part of the water cooling jacket on the furnace wall, the slag will be reliably separated at the boundary between the furnace lid and the furnace wall when the furnace lid moves up and down. It will not fall outside the furnace.

[0015]

【Example】

 An embodiment of the present invention will be described below. The present embodiment is an example in which the present invention is applied to an arc furnace for steelmaking. The nominal capacity of the steelmaking arc furnace of this example is 80 tons.

FIG. 1 is a front view of an arc furnace for steelmaking of the present embodiment, in which 1 is a shell, 2 is a furnace lid, 3 is an electrode, 4 is an electrode supporting arm, 5 is a cable, and 6 is a furnace lid lift. The swivel, and 7 is the work floor.

FIG. 2 (a) is a partial cross-sectional view of a portion of the arc furnace for steelmaking of the present embodiment related to the present invention, in which the water cooling jacket 14 at the uppermost stage of the furnace wall 13 is located above the upper surface of the furnace bezel 8. The end surface is lowered by about 40 mm, which indicates that the upper end surface of the water cooling jacket 14 is additionally provided with a plurality of additional steel slag adhering studs 15T. As a result of the additional steel slag adhering stud 15T, the slag 16 adheres to the upper part of the water cooling jacket 14 more strongly than before, and when the furnace lid 2 is lifted upward, it breaks and separates around the broken line portion of B-BB. Therefore, the slag 16 is no longer lifted while being attached to the outer peripheral portion of the lower surface of the furnace lid 2 in a suspended shape (icicle shape).

FIG. 2B is a perspective view showing the positional relationship between the furnace shell bezel 8 and the upper end surface of the uppermost water-cooling jacket 14 of the furnace wall 13 and the condition of the additional steel slag adhering studs 15T. is there. As described above, in providing the additional steel slag adhesion studs 15T, various experiments were conducted on the shape, the mounting location, the mounting interval and the arrangement of the additional steel slag adhesion studs 15T, and the results are shown in FIGS. 2 (a) and 2 (b). The mounting method was the most effective. By the way, the additional steel slag adhering stud 15T in this embodiment has a mushroom shape similar to the stud 17 on the lower surface of the water cooling jacket of the furnace lid, and the mounting interval is about 10 cm, and the upper end surface of the water cooling jacket 14 has a staggered arrangement. did.

[0019]

[Effect of device]

 The present invention provides an arc furnace for melting and refining steel or ferroalloy iron, wherein a plurality of steel slag adhering studs are additionally provided on the upper end surface of the water cooling jacket of the furnace wall of the arc furnace. The thick slag that adheres to the boundary between the lid and the furnace wall drops when the furnace lid moves up and down from the main body of the arc furnace, damaging the equipment attached to the arc furnace or equipment near the arc furnace, and dropping. It is possible to solve the problem that a large number of man-hours are required for removing and cleaning slag, and improve safety and maintainability.

[Brief description of drawings]

FIG. 1 is a schematic front external view of an arc furnace for steelmaking of this example.

FIG. 2 (a) is a partial cross-sectional view showing the positional relationship between the furnace bezel according to the present invention and the upper end surface of the water cooling jacket at the uppermost stage of the furnace wall, and the positional condition in which an additional steel slag adhering stud is additionally provided. is there. (B) is a perspective view showing the above (a) diagram in an easily understandable manner.

FIG. 3 is a partial cross-sectional view of a steelmaking arc furnace for explaining a conventional technique according to the present invention.

[Explanation of reference symbols] 1 furnace shell 2 furnace lid 3 electrode 4 electrode support arm 5 cable 6 furnace lid lifting and swiveling device 7 working floor 8 furnace shell bezel 12 molten steel 13 furnace wall 14 water cooling jacket 15 steel slag adhesion stud (square pillar) 15T Additional steel slag adhesion studs 16 Slag 16H Drop slag 17 Steel slag adhesion studs (mushroom shape)

Claims (1)

[Scope of utility model registration request] 1. An arc furnace for melting and refining iron or steel alloys, wherein a plurality of steel slag adhering studs are provided on an upper end surface of a water cooling jacket of a furnace wall of the arc furnace main body, and a slag dropping on a furnace lid is performed. Electric arc furnace with protection.