JP2018192523A - Slag-removal equipment - Google Patents

Abstract

To provide a slag-removal equipment capable of properly preventing erosion of a raking plate by properly setting a refractory coverage range for the raking plate and of preventing a weight increase of the raking plate.SOLUTION: A slag-removal equipment 1 is attached at a tip of a raking arm 18 with a raking plate 30 that rakes out a slag S floating in a surface of a molten metal M within a molten-metal vessel 50, which the raking plate 30 is configured by a quadrangular plate extending in longitudinal and vertical directions. The raking plate 30 is provided with a refractory 34 covering a front face 30a and a rear face 30b, a left side face 30e and a right side face 30f, and a lower end surface 30d in a lower part of the raking plate 30. The coverage range R of the refractory 34 over the raking plate 30 is 30 mm or greater and 300 mm or smaller from a bottom edge of the raking plate 30.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a hair removal device that scrapes and removes slag floating on the surface of a molten metal poured into a molten metal container from a blast furnace or the like.

  The surface of the hot metal (molten metal) in the hot metal ladle (molten metal container) after being discharged from the blast furnace and desulfurized is covered with slag. It is necessary to scrape and remove the slag that floats over the surface of the hot metal, and the slag removal operation is one of the operations indispensable in the steelmaking and steelmaking processes. In the slag removal work, it is common to use a slag remover called a slag dragger.

Conventionally, for example, a device disclosed in Patent Document 1 is known as this type of debridement device.
The removal apparatus shown in Patent Document 1 includes a slag dragger having a scraping plate provided at the tip of a scraping arm, a hot water level sensor for measuring the height of the molten metal, and a consumption amount of the scraping plate. It comprises a consumption amount measuring mechanism for measuring, and a control device for controlling the height of the scraping plate with respect to the height of the molten metal surface based on the measured value of the consumption amount of the scraping plate. Then, after scraping for a predetermined stroke, the consumption amount of the scraping plate is measured using the consumption amount measuring mechanism, and the difference from the reference length of the scraping plate before consumption is corrected to scrape the surface relative to the height of the molten metal surface. The front end position of the plate is controlled to an appropriate position so that the scraped plate is always immersed in the slag at a constant immersion depth.
According to the removal apparatus shown in Patent Document 1, even if the scraping plate is consumed, the scraping plate can follow the height of the hot water surface by the consumed amount, and the efficiency and automation of the slag scraping can be controlled under the operating conditions. The effect is that it can be achieved regardless.

Moreover, what is shown, for example in patent document 2 is also known as another example of the conventional exclusion method.
The evacuation method shown in Patent Document 2 arranges a plurality of scraping plates with arms on the left and right with overlapping portions in front and back, and moves the scraping plates to the left and right within the range where the overlapping portions remain to match the container shape. Thus, the entire length of the row of scraping plates is expanded and contracted to scrape the molten iron in the container.
According to the evacuation method shown in Patent Document 2, by preventing the slag from falling, it is possible to prevent a significant reduction in efficiency and to significantly reduce the time required for removal.

  However, in the removal apparatus shown in these patent documents 1 and the removal method shown in patent documents 2, it cannot avoid that a scraping board is exposed to high temperature molten metal, and melts. In the case of the removal device shown in Patent Document 1, even if the scraping plate is melted, the scraping plate can follow the height of the molten metal surface by the amount of the melted damage. The scraping plate must be replaced manually, which does not lead to a fundamental reduction in personnel. Further, in the case of the evacuation method shown in Patent Document 2, when the scraping of the scraping plate occurs, it takes a long time to replace the scraping plate, which leads to a reduction in operating rate.

On the other hand, as a means for preventing the scraped plate from being worn, for example, a castable coating device for a desulfurization plate of a slag dragger shown in Patent Document 3 is known.
In the castable coating apparatus shown in Patent Document 3, refractory castables are applied to both front and back surfaces of the lower half of the slag dragger desulfurization plate to prevent the desulfurization plate from being melted.

JP-A-9-243273 JP 2000-227282 A Japanese Patent Publication No.57-58993

However, the castable coating apparatus for the slag dragger desulfurization plate shown in Patent Document 3 has the following problems.
That is, in the castable coating apparatus shown in Patent Document 3, the refractory castable is applied to both front and back surfaces of the lower half of the slag dragger desulfurization plate. Has not been considered. For this reason, when scraping out the slag on the surface of the molten metal at the lower end side of the desulfurization plate, the coating range of the refractory castable desulfurization plate is too small and the molten metal directly contacts the desulfurization plate and melts down. There is a possibility that the weight of the desulfurization plate is too heavy because the refractory castable is covered in an excessive range.

  In the case of the castable coating apparatus shown in Patent Document 3, since the fire-resistant castable is coated on both the front and back surfaces of the lower half of the slag dragger desulfurization plate, there is a concern that the coating range of the fire-resistant castable desulfurization plate is too small. May be small, but the possibility that the desulfurization plate is too heavy cannot be avoided. If the weight of the desulfurization plate is too heavy, the scraping arm of the slag dragger to which the desulfurization plate is attached bends more than necessary, or it is necessary to make the scraping arm robust in order to avoid the bending.

  Therefore, the present invention has been made to solve this problem. The purpose of the present invention is to appropriately set the coating range of the refractory scraping plate to prevent the scraping plate from being melted and to prevent the scraping plate from being damaged. An object of the present invention is to provide a hair removal device capable of preventing an increase in weight.

  In order to achieve the above object, a scissoring apparatus according to one aspect of the present invention is provided with a scraping plate that scrapes off the slag floating on the surface of the molten metal in the molten metal container at the tip of the scraping arm. A stripping device having a quadrilateral shape extending in a vertical direction and a vertical direction, wherein the scraping plate is provided with a refractory covering the front and back surfaces, the left and right side surfaces, and the bottom surface of the scraping plate, The gist of the covering range of the scraping plate is from 30 mm to 300 mm from the lower end of the scraping plate.

  According to the scissoring apparatus according to the present invention, there is provided a scissoring apparatus that can appropriately set the covering range of the refractory material to the scraping plate to prevent the scraping plate from being melted and prevent the scraping plate from becoming heavy. it can.

It is a schematic block diagram of the hair removal apparatus which concerns on one Embodiment of this invention. It is a front view which shows the scraping board in the dehairing apparatus shown in FIG. It is sectional drawing which follows the 3-3 line in FIG. The scraper plate was designated as Invention Example 1 (with refractory), Invention Example 2 (with refractory (SiC added)), Comparative Example 1 (without refractory), and Comparative Example 2 (outside the refractory coating range). It is a graph which shows the lifetime of the scraping board in the case of.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. It should be noted that the drawings are schematic, and the dimensional relationship between elements, the ratio of elements, and the like may differ from actual ones. Even between the drawings, there are cases in which parts having different dimensional relationships and ratios are included.

  1 removes the slag S floating on the surface of the molten iron (molten metal) M in the hot metal ladle (molten metal container) 50 after being discharged from the blast furnace and desulfurized. The traveling frame 10 capable of traveling forward and backward indicated by arrow A, the turning frame 11 capable of turning by the turning motor 12 on the traveling frame 10, and the slide motor 15 on the turning frame 11 in the front-rear direction. A slidable slide frame 13 and a scraping arm 18 that moves up and down like a seesaw via a saddle 16 on the slide frame 13 are provided. In FIG. 1, reference numeral 14 is a heat insulating plate attached to the tip of the slide frame 13, 19 is a hydraulic unit, 20 is a driver's cab, 21 is a drive for a swing motor 12, a slide motor 15 and a raking arm cylinder 17 described later. The control panel 60 is a crane for the hot metal ladle 50.

When the slide frame 13 is slid forward on the revolving frame 11 by the slide motor 15 as indicated by the arrow A, the tip (front end) of the scraping arm 18 is at the back side (front side) in the hot metal ladle 50 as shown in FIG. When the slide frame 13 is slid rearwardly as indicated by the arrow B by the slide motor 15 on the revolving frame 11, the tip moves to the front side (rear side) of the hot metal ladle 50 and is formed in the hot metal ladle 50. The slag S is scraped out from the opening 50a.
Further, between the saddle 16 and the rear end of the scraping arm 18, there is provided a scraping arm cylinder 17 that expands and contracts upward as indicated by arrow C and downward as indicated by arrow D, and the scraping arm cylinder 17 is indicated by arrow C. When extended upward, the scraping arm 18 rotates downward and its tip is positioned downward as shown in FIG. 1. When the scraping arm cylinder 17 contracts downward as indicated by arrow D, the scraping arm 18 rotates upward. The tip is positioned above.

  A scraping plate 30 that scrapes the slag S floating on the surface of the hot metal M in the hot metal ladle 50 is attached to the tip of the scraping arm 18. 2 and 3, the scraping plate 30 is a rectangular flat plate having a predetermined thickness t in the front-rear direction, a height h1 and a width w extending in the left-right direction and the vertical direction, (Front surface) 30a, rear surface (back surface) 30b, upper end surface 30c, lower end surface 30d, left side surface 30e, and right side surface 30f. Here, the thickness t of the scraping plate 30 is preferably 10 mm or more and 50 mm or less. If the plate thickness t is smaller than 10 mm, the writing plate 30 is not strong enough and the scraping plate 30 may be bent during processing. On the other hand, if the plate thickness t is larger than 50 mm, the scraped plate 30 is increased in weight. In the present embodiment, the height h1 of the scraping plate 30 is 400 mm, and the width w is 540 mm.

A plate member 32 is fixed to the upper end surface 30 c of the scraping plate 30, and a mounting portion 33 to the scraping arm 18 is provided on the upper end surface of the plate member 32. The scraping plate 30 is attached to the scraping arm 18 by attaching the mounting portion 33 to the tip (front end) of the scraping arm 18 with the rear surface 30b of the scraping plate 30 facing rearward of the depigmenting device 1 and the front surface 30a facing forward. It is done.
A pair of horizontal plates 31 extending in the vertical direction are fixed in the vicinity of the left and right side surfaces 30e, 30f of the rear surface 30b of the scraping plate 30. These horizontal plates 31 have a function of preventing the slag S from deviating from the left and right sides of the scraping plate 30 when scraping the slag S by the scraping plate 30. In the present embodiment, the height h2 of each horizontal plate 31 from the rear surface 30b of the scraping plate 30 is 50 mm, and the width b is 25 mm.

The scraper plate 30 is provided with a refractory 34 that covers the lower front surface 30a and rear surface 30b, the left side surface 30e and the right side surface 30f, and the lower end surface 30d of the scraper plate 30.
The covering range of the refractory 34 on the scraping plate 30 is indicated by a symbol R in FIG. 2, and is 30 mm or more and 300 mm or less from the lower end of the scraping plate 30. Thereby, the covering range R with respect to the scraping plate 30 of the refractory 34 can be set appropriately to prevent the scraping plate 30 from being melted properly and to prevent the scraping plate 30 from being increased in weight. When the covering range R is smaller than 30 mm from the lower end of the scraping plate 30, when the scraping plate 30 scrapes the slag S, the scraping plate 30 may directly come into contact with the hot metal. There is a risk of damage. On the other hand, when the covering range R is larger than 300 mm from the lower end of the scraping plate 30, the scraping plate 30 is increased in weight.

Further, the protrusion height T of the refractory 34 downward from the lower end of the scraping plate 30 is 70 mm in the present embodiment, but is preferably 20 mm or more and 150 mm or less. When the protrusion height T is smaller than 20 mm from the lower end of the scraping plate 30, there is a disadvantage that the refractory is not fixed sufficiently by the stud pin and the refractory falls off. On the other hand, when the protrusion height T is larger than 150 mm from the lower end of the scraping plate 30, the scraping plate 30 is increased in weight.
Moreover, although the width W of the left-right direction of the refractory 34 is 600 mm in this embodiment, it is preferable that it is 500 mm or more and 800 mm or less. If the width W is smaller than 500 mm, there is a disadvantage that it takes time to complete the scraping. On the other hand, if the width W is greater than 800 mm, the scraping plate 30 is increased in weight.

Furthermore, the thickness L in the front-rear direction of the refractory 34 is 150 mm in this embodiment, but is preferably 100 mm or more and 150 mm or less. If the thickness L is smaller than 100 mm, the scraping plate is not strong enough and the scraping plate is bent during processing. On the other hand, when the thickness L is larger than 150 mm, the scraped plate 30 is increased in weight.
The chemical components of the refractory 34 will be described. The refractory 34 contains Al ₂ O _{3 in an amount} of 30 wt% to 70 wt% and SiO ₂ in an amount of 20 wt% to 60 wt%. Thereby, the melt resistance of the refractory 34 is improved, the mechanical strength is increased, and the cost can be reduced. When the content of Al ₂ O ₃ is less than 30 wt%, there is a disadvantage that the corrosion resistance and spalling resistance are lowered. On the other hand, when the content of Al ₂ O ₃ is larger than 70 wt%, there is a disadvantage that the slag penetration resistance is lowered.

Moreover, the refractory 34 contains 0 wt% or more and 15 wt% or less of SiC. Since the spalling resistance is improved by containing SiC, the refractory 34 is preferably contained rather than containing SiC. When the spalling resistance of the refractory 34 is improved, for example, durability when the refractory 34 collides with the hot metal ladle 50 during the slag S scraping operation is improved. On the other hand, when the content of SiC is more than 15 wt%, there is a disadvantage that it is easily eroded by hot metal.
When constructing the refractory 34 on the scraping plate 30, a plurality of stud pins 35 are fixed to the lower portion (refractory construction place) of the scraping plate 30, and the raw material of the refractory 34 is poured into the mold, After the refractory 34 is cured, the mold may be removed.

Next, a method for scraping out the slag floating on the surface of the hot metal M in the hot metal ladle 50 by the demetalizer 1 will be described.
First, as shown in FIG. 1, the hot metal ladle 50 is tilted by the crane 60 so that the slag S can be scraped out by the scraping arm 18.
Next, the demolition device 1 is moved to a predetermined position, and the turning position of the revolving frame 11 is adjusted so that the scraping arm 18 faces the hot metal ladle 50 by controlling the driving of the revolving motor 12.
Thereafter, the drive of the slide motor 15 is controlled so that the slide frame 13 is slid forward as indicated by the arrow A, the tip of the scraping arm 18 is moved to the back side (front side) in the hot metal ladle 50, and the scraping arm cylinder 17 is moved. Is extended upward as indicated by arrow C, and the lower end of the scraping plate 30 attached to the tip of the scraping arm 18 is inserted into the hot metal M. At this time, the scraper plate 30 is provided with a refractory 34 that covers the lower front surface 30a and rear surface 30b, the left side surface 30e and the right side surface 30f, and the lower end surface 30d of the scraper plate 30. There is no direct contact with the scraping plate 30.

The covering range R of the refractory 34 with respect to the scraping plate 30 is 30 mm or more from the lower end of the scraping plate 30, so the risk that the hot metal M directly contacts the scraping plate 30 is extremely low. Can be prevented appropriately. Further, since the covering range R of the refractory 34 with respect to the scraping plate 30 is 300 mm or less from the lower end of the scraping plate 30, an increase in the weight of the scraping plate 30 can be prevented.
Then, the drive of the slide motor 15 is controlled to slide the slide frame 13 backward as indicated by arrow B, and the scraping plate 30 attached to the tip of the scraping arm 18 is moved to the front side (rear side) in the hot metal ladle 50. The slag S floating on the surface of the hot metal M is scraped out from the opening 50 a of the hot metal pan 50.
Thereafter, the scraping arm cylinder 17 is contracted downward as indicated by an arrow D, and the lower end of the scraping plate 30 attached to the tip of the scraping arm 18 is taken out from the hot metal M.
When the scraping operation of the slag S is repeated as many times as necessary, the operation is finished.

As mentioned above, although embodiment of this invention has been described, this invention is not limited to this, A various change and improvement can be performed.
For example, the slag S scraped out by the demetallizer 1 is not intended for only those floating on the surface of the molten iron M in the hot metal ladle 50, but other molten metals such as those floating on the molten steel in the molten steel pan. The target is one that floats on the surface of the molten metal in the container.
The scraping plate 30 is not limited to a rectangular flat plate, and may be another rectangular flat plate such as a square flat plate.

Next, in order to verify the effect of the present invention, a life test of the scraped plate was performed.
The scraping plate of Comparative Example 1 to be tested is a scraping plate having a configuration shown in FIGS. 2 and 3 in which no refractory is applied. That is, the scraping plate of Comparative Example 1 is as follows.
A rectangular flat plate having a plate thickness t = 25 mm, a vertical height h1 = 400 mm, and a horizontal width w = 540 mm, and each horizontal plate has a height h2 = 50 mm from the rear surface of the scraped plate and a width b. = 25mm

Moreover, as a scraping plate of the comparative example 2 used as a test object, although it is a scraping plate of the structure shown in FIG.2 and FIG.3, let the covering range R of a refractory be a 20 mm scraping plate which is less than the range of this invention. However, SiC is not added as a chemical component of the refractory. That is, the scraping plate of Comparative Example 2 is as follows.
Covering range R of the refractory scraping plate R = 20 mm, projecting height T = 70 mm downward from the lower end of the refractory scraping plate 30, refractory height H 130 mm, refractory width W = 600 mm , Thickness L = 150mm in the front-rear direction of the refractory
Refractory Al ₂ O ₃ content 48 wt%, SiO ₂ content 40 wt%

Further, the scraping plate of Invention Example 1 to be tested is a scraping plate having the structure shown in FIGS. 2 and 3, and SiC is not added as a chemical component of the refractory. That is, the scraping plate of Example 1 of the present invention is as follows.
A rectangular flat plate having a plate thickness t = 25 mm, a vertical height h1 = 400 mm, and a horizontal width w = 540 mm, and each horizontal plate has a height h2 = 50 mm from the rear surface of the scraped plate and a width b. = 25 mm, Refractory scraping plate covering range R = 60 mm, refractory scraping plate 30 projecting height T from bottom to bottom T = 70 mm, refractory height H 130 mm, refractory left and right direction Width W = 600mm, refractory thickness L = 150mm
Refractory Al ₂ O ₃ content 48 wt%, SiO ₂ content 40 wt%

Furthermore, the scraper plate of Invention Example 2 to be tested is a scraper plate having the structure shown in FIGS. 2 and 3, and SiC is added as a chemical component of the refractory. That is, the scraping plate of Example 2 of the present invention is as follows.
A rectangular flat plate having a plate thickness t = 25 mm, a vertical height h1 = 400 mm, and a horizontal width w = 540 mm, and each horizontal plate has a height h2 = 50 mm from the rear surface of the scraped plate and a width b. = 25 mm, Refractory scraping plate covering range R = 60 mm, refractory scraping plate 30 projecting height T from bottom to bottom T = 70 mm, refractory height H 130 mm, refractory left and right direction Width W = 600mm, refractory thickness L = 150mm
Refractory Al ₂ O ₃ content 45 wt%, SiO ₂ content 43 wt%, SiC content 9 wt%

The test results are as shown in FIG. That is, in the case of the scraping plate of Comparative Example 1, the life of the slag removal work (number of hot metal pans for removing the slag) is five times per sheet, whereas the scraping plate of the present invention example 1 is used. The slag removal work can be performed 50 times per sheet, and in the case of the scraping plate of Example 2 of the present invention, the slag removal work can be performed 90 times per sheet.
That is, when a refractory was applied to the scraped plate, its life was 10 times longer, and when SiC was added to the refractory, its life was 1.8 times longer than when no refractory was added. .
However, even when the refractory material is applied to the scraper plate, in the case of Comparative Example 2 in which the refractory covering range R is lower than the range of the present invention, the hot metal contacts the scraper plate directly. The slag removal work per 8 times had reached the end of its life, and the life was short.

DESCRIPTION OF SYMBOLS 1 Derailment device 10 Traveling frame 11 Swing frame 12 Swing motor 13 Slide frame 14 Heat shield 15 Slide motor 16 Saddle 17 Scraping arm cylinder 18 Scraping arm 19 Hydraulic unit 20 Operating room 21 Control panel 30 Scraping plate 30a Front (surface)
30b Rear side (back side)
30c Upper end surface 30d Lower end surface 30e Left side surface 30f Right side surface 31 Horizontal plate 32 Plate material 33 Mounting portion 34 Refractory 35 Stud pin 50 Hot metal ladle (molten metal container)
50a Opening 60 Crane M Hot metal (molten metal)
R Coverage range S Slag

Claims (2)

A scraping plate for scraping slag floating on the surface of the molten metal in the molten metal container is attached to the tip of the scraping arm, and the scraping plate has a quadrilateral shape extending in the left-right direction and the vertical direction,
The scraper plate is provided with a refractory covering the front and back surfaces of the lower portion of the scraper plate, the left and right side surfaces, and the lower end surface, and the covering range of the refractory to the scraper plate is 30 mm or more and 300 mm from the lower end of the scraper plate. A device for removing hair characterized by the following. _2. The removal according to claim 1, wherein the refractory contains Al ₂ O ₃ of 30 wt% or more and 70 wt% or less, SiO ₂ of 20 wt% or more and 60 wt% or less, and SiC of 0 wt% or more and 15 wt% or less. apparatus.

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