WO2018116784A1

WO2018116784A1 - Plate for sliding nozzle device

Info

Publication number: WO2018116784A1
Application number: PCT/JP2017/043170
Authority: WO
Inventors: 岡田　剛; 康平谷; 英俊神尾; 善太王丸; 昭二規工川; 幸司瓦田
Original assignee: 黒崎播磨株式会社
Priority date: 2016-12-21
Filing date: 2017-11-30
Publication date: 2018-06-28
Also published as: TWI655980B; TW201829091A; JP7017935B2; JPWO2018116784A1

Abstract

The purpose of the present invention is to suppress or reduce occurrences of ingot insertion between sliding surfaces of a plate in a form not caused by some damage to this sliding surface of the plate or occurrences of gaps accompanying the same. Thus, in the present invention, a sheet shaped heat resistant material 3 is provided in part or the entire area in the vicinity of dowel parts (2a, 2b) at the periphery of an inner hole in the surface ("rear surface" in the following) on the side opposite to the sliding surface, so as to protrude in the direction of thickness of the plate more than other flat surface parts of the rear surface; or a plate main body has a region with a thickness thicker than other regions of the plate is provided, and the sheet-shaped heat resistant material is provided; or the area with a thickness greater than other areas of the plate main body is in contact with at least part of a metal frame for a sliding nozzle device securing the rear surface side of the plate.

Description

Plate for sliding nozzle device

The present invention relates to a plate structure used in a sliding nozzle device for controlling a flow rate when discharging molten metal from a molten metal container.

The plate for the sliding nozzle device (hereinafter also simply referred to as “plate”) is a plate-like structure having an inner hole for discharging molten metal. In addition, the sliding nozzle device controls the flow rate of the molten metal by sliding the two or three independent plates relative to each other and changing the area of the opening portion where the inner holes of the plates overlap. .

The plate is exposed to high temperatures above the melting point of the molten metal in the vicinity of its inner hole, and since it is used repeatedly, it is severe for refractory materials, such as undergoing a large temperature change between the high temperature range and the atmospheric temperature range. Used in conditions. In addition, the plate is fixed to the metal frame of the sliding nozzle device, so that no molten metal leakage (hereinafter referred to as “bare metal” or “leakage steel”) occurs between the sliding surfaces of the plates. Is subjected to a high pressure in the direction in which the plates are pressed together (hereinafter also referred to as “longitudinal direction”) (hereinafter, this pressure is also referred to as “surface pressure”).
With respect to this surface pressure, for example, in Patent Document 1, a back cushion material (cushion material + cushioning material + (Including metal sheets or multilayer metal sheets) is shown to be larger than the plate outline, that is, attached to the entire back surface of the plate.

Such a plate may have various cracks, damage to the sliding surface, opening between the sliding surfaces, etc. during or after use, reducing the durability of the plate and inserting metal between the sliding surfaces. The problem is occurring. Above all, the problem of inserting metal between sliding surfaces is a serious problem with the potential to lead to a large-scale steel leakage accident.
The metal insert between the sliding surfaces is pointed out as a result of gaps between the sliding surfaces due to damage caused by wear, chemical erosion, oxidation, etc. of the sliding surfaces due to swelling or chipping of the inner hole edge. Has been.

As one of countermeasures against damage between such sliding surfaces, for example, in Patent Document 2, there is no swelling or chipping of the edge portion of the inner hole, which is caused by thermal expansion accompanying molten steel passing through the inner hole. It is proposed to provide a concave surface with a depth of 0.1% to 2% of the thickness of the plate brick so as to surround the nozzle hole (inner hole) at the edge of the inner hole on the sliding surface side of the plate brick. ing. By this concave surface, it is said that the compressive stress due to the warpage of the plate brick caused by thermal expansion is relieved, and the wear of the sliding surface stroke part and the chipping of the nozzle hole edge part can be reduced.
Patent Document 3 proposes a plate refractory formed by molding a composition mainly composed of silicon iron nitride 0.1 to 50 wt%, the balance being a refractory material and a carbon material. This silicon iron nitride is said to improve the oxidation resistance of the plate and reduce damage to the sliding surface due to oxidation.

In addition to such a surface pressure, the plate is also fastened and fixed from a direction perpendicular to the longitudinal direction (hereinafter also referred to as “lateral direction”). This lateral fixing is generally performed by pressing the vicinity of the four corners of the plate plane shape diagonally. However, if this lateral position is shifted between two or three plates, chipping is likely to occur at the shifted portion of the inner hole edge of each plate, which may cause damage between the sliding surfaces. Become.
As a measure for preventing this deviation, Patent Document 4 discloses that a frame (main body) is formed in the vicinity of the discharge port on the back side of the plate (corresponding to the “inner hole” in the present invention). This corresponds to the “gold frame” in the present invention), and is centered (ie, placed at an accurate position) by being fitted into a recess formed.
The convex portion of Patent Document 4 is formed by bending a rib, and does not exert pressure (surface pressure) in the longitudinal direction (surface pressure application side).

JP-A-2-169175 Japanese Patent Laid-Open No. 11-57989 Japanese Patent Laid-Open No. 2-108456 Japanese Patent No. 4446598

The causes and countermeasures shown in these patent documents have been confirmed to be effective individually in some actual operations. However, as a result of detailed examinations by the present inventors, there is a case in which the metal insertion phenomenon between the sliding surfaces of the plate is not necessarily caused by any damage to the sliding surface or the occurrence of a gap associated therewith. all right. In other words, it has been found that there is a form that cannot be solved by the countermeasures of the above-mentioned patent document, which mainly causes damage to the sliding surface, as a bullion insertion phenomenon between the sliding surfaces.

The problem to be solved by the present invention is to suppress or reduce the occurrence of metal squeezing between the sliding surfaces of the plates in a form that does not depend on any damage to the sliding surfaces or the occurrence of gaps associated therewith.

The present invention is a plate for a sliding nozzle device described in 1 to 5 below.
1.
The length of the surface opposite to the sliding surface (hereinafter referred to as “rear surface”) is twice the length from the short side end to the center of the inner hole starting from the short side end. A sheet-like heat-resistant material that protrudes in the thickness direction of the plate from the other flat part of the back surface in part or all of the area near the dowel part around the inner hole that is within the range to the shank side position Is installed, or the plate body has a thicker area than other areas,
The area where the sheet-like heat-resistant material is installed or the thickness of the plate body is thicker than other areas is in contact with at least a part of the metal frame of the sliding nozzle device for fixing the back side of the plate. The sliding nozzle device plate.
2.
The plate is one or both of an upper plate mounted in contact with the fixed metal frame on the molten steel container side of the sliding nozzle device and a lower plate mounted in contact with the lower slide metal frame. The plate for a sliding nozzle apparatus as described.
3.
The sheet-like heat-resistant material is either a sheet obtained by molding a fibrous inorganic material or a plate-like metallic material, or a multilayer structure thereof, according to either 1 or 2 above. Plate for sliding nozzle device.
4).
The thickness of the plate body thicker than the other region or the thickness of the sheet-like heat-resistant material protruding in the thickness direction of the plate from the other region is 0.1 mm or more and 1.6 mm or less. 4. The sliding nozzle device plate according to any one of 1 to 3 above.
5).
The sheet-like heat-resistant material is either a sheet formed mainly from a fibrous inorganic material, a plate-like metallic material, or the surface of another sheet-like heat-resistant material that is a multilayer structure thereof. 5. The sliding nozzle device plate according to any one of 1 to 4, which is installed.

The details will be described below.

In Patent Document 2, since the inner hole surface through which the molten steel passes has the highest temperature and the expansion of the plate increases, the inner surface of the sliding surface of the plate tends to protrude (phenomenon). It tries to suppress the phenomenon by denting the vicinity. However, although such a phenomenon may actually be observed, the end of the upper and lower plates may come into strong contact with each other, and the sliding surface near the center (near the inner hole) may open. They discovered. Which of these phenomena occurs, and the extent to which, in particular, the degree of fixation in the sliding direction (longitudinal direction) of the plate, the length and thickness of the sliding direction (longitudinal direction) of the plate, the physical properties of the plate, the plate It can be considered that a plurality of elements such as the fixed structure such as the upper and lower nozzles are related to each other. However, when the vicinity of the center is warped, it tends to occur so that the opening near the inner hole is maximized.
As described above, between the sliding surfaces of the plates, a pressure perpendicular to the sliding surface, that is, a so-called surface pressure is applied. However, in general, cushioning materials and iron plates are often installed on the back of the plate to disperse the surface pressure for the purpose of preventing cracks, etc., and these cushioning materials and iron plates are used during hot use. Due to various factors such as shrinkage and deformation, dimensional fluctuation in the direction of surface pressure is likely to occur, which also contributes to warpage in the longitudinal direction of the plate.

According to the present invention, the flat portion near the dowel portion on the back surface of the plate protrudes in a direction perpendicular to the sliding surface with respect to the sliding surface more than the other flat portions, so that the sliding at least near the inner hole is achieved. Correct the opening of the surface, that is, reduce the gap. As a specific configuration for this correction, in the present invention, a part or all of the area near the dowel around the inner hole protrudes in the plate thickness direction (vertical direction) from the other flat part of the back surface. As described above, a sheet-like heat-resistant material is installed, or the thickness of the plate body in the region is made thicker than other regions.
Further, the sheet-like heat-resistant material is installed, or the region where the thickness of the plate body is thicker than other regions is a fixed metal frame above the sliding nozzle device for fixing the back side of the upper plate, And at least a part of one or both of the lower slide metal frames that fix the back side of the lower plate. By contacting in this way, the gap between the metal frame and the sheet-like heat-resistant material surface on the back side of the plate in the direction perpendicular to the sliding surface or the surface of the plate body thicker than other regions Or the pressure-bonding force is transmitted more strongly than the region other than the vicinity of the dowel portion.

According to the present invention, it is possible to suppress or reduce the occurrence of metal squeezing between the sliding surfaces of the plates in a form that does not depend on any damage to the sliding surfaces or the occurrence of gaps associated therewith.

It is an example of the plate of this invention, Comprising: It is an image figure which shows the case where a sheet-like heat-resistant material is affixed on the whole object area | region of the dowel part vicinity, (a) is a plane image, (b) is a cross-sectional image. It is a plane image at the time of thickening the plate main body of the same area | region as FIG. 1A. When a pair of sheet-like heat-resistant materials are attached to the center of the inner hole and symmetrical to the direction perpendicular to the sliding direction, or when the plate body is thickened (at least according to the outer shape of the end of the plate in the width direction) This is a planar image of a case where a sheet-like heat-resistant material is attached to a region covering the inner hole width in the plate width direction or the plate body is thickened. It is a planar image when a pair of sheet-like heat-resistant materials are affixed to the center of the inner hole and symmetrical to the sliding direction, or when the plate body is thickened. Is a planar image when a sheet-like heat-resistant material is pasted around the dowel, or when the plate body is thickened. It is an image figure which shows the example of the conventional plate, (a) is a plane image, (b) is a cross-sectional image. It is an image figure which shows the example of the state (The state seen from the sliding surface side which opened the slide metal frame) which set the plate to the sliding nozzle apparatus. In the experiment which investigated the surface pressure by a sensor sheet | seat and the pressure distribution between plate sliding surfaces of the experiment example A, it is an image figure which shows the set place of a sensor sheet | seat. The experimental result of the said experimental example A is shown, (a) is the measurement result which looked at the pressure distribution detected with the said sensor sheet | seat from the sliding surface of the plate, (b) is every measuring point of the number in said (a). It is a graph which shows the magnitude | size of the surface pressure of and the relationship between a pressure. It is an image figure which shows the example of the crack which generate | occur | produces when a sheet-like heat-resistant material is installed too thickly. In the experiment in which the pressure distribution between the plate sliding surfaces by pressure sensitive paper was examined in Experimental Example B, (a) is an image diagram showing the setting location of the pressure sensitive paper, and (b) is a diagram showing the surface pressure distribution appearing on the pressure sensitive paper (Photo).

¡Since the metal insert between the sliding surfaces of the plate is generated around the inner hole of the plate, it is important to suppress the generation of gaps around the inner hole. The pressure that presses the sliding surface around the inner hole in the vertical direction has been found by experiments of the present inventors to be low even if the vertical pressure (surface pressure) applied to the entire plate is increased. did.

Therefore, in the present invention, in order to concentrate pressure (surface pressure) around the inner hole, as a first means, other planes on the back surface are provided in a part or all of the vicinity of the dowel portion on the back surface of the plate. A sheet-like heat-resistant material is installed so as to protrude in the thickness direction of the plate from the portion. More specifically, the sheet-like heat-resistant material includes a metal frame for mounting the plate (a fixed metal frame (reference numeral 10 in FIG. 3) in the case of the upper plate, and a slide metal frame (reference numeral 11 in FIG. 3) in the case of the lower plate. )) Is installed at a position where it can contact at least a part of the surface and transmit the pressure in the direction perpendicular to the sliding surface. That is, the sheet-like heat insulating material is installed so as to transmit the crimping force between the metal frame more strongly than the region other than the vicinity of the dowel portion. The sheet-like heat-resistant material only needs to have heat resistance enough to maintain shape retention at the temperature during use.

Here, “the dowel portion” means a convex portion around the inner hole (for example, a portion 2a in FIG. 1A) and other nozzles such as an upper nozzle and a lower nozzle fitted on the convex portion on the back surface of the plate. This refers to a portion that is combined with a portion that contacts (for example, the portion 2b in FIG. 1A).

Further, the region in the vicinity of the dowel portion is twice the length from the short side end portion to the center of the inner hole (Ls in FIG. 1A (a)) where the plate sliding direction starts from the short side end portion. In the range up to the long side position, the plate width direction is in the entire range of the sliding direction side range, that is, the hatched portion in FIG. 1A (a).

In the region near the dowel, the maximum region in the plate sliding direction is, for example, in the sliding nozzle device composed of two upper and lower plates, the longest portion on the long side of the overlapping portion during casting is the short length of the opposite plate. Depending on the side edge. In other words, there is a case where there is no opposite plate in the long side region beyond the short side end in the sliding direction. This is to avoid the fact that it acts in the direction of opening the sliding surface on the opposite side of the moving direction. The short side means the short side with reference to the inner hole of the plate, and the long side means the long side with reference to the inner hole of the plate (see FIG. 1A (a)).

The sheet-like heat-resistant material is installed in at least a part of the region in the vicinity of the dowel part (part or all of the region in the vicinity of the dowel part).
For example, (1) You may install symmetrically (two places) only in the direction perpendicular to the sliding direction, that is, near both ends of the plate on the imaginary line passing through the center of the inner hole in the plate width direction (see FIG. 1C). Moreover, (2) You may install symmetrically (two places) only near the plate both ends on the imaginary line which passes an inner hole center in a plate sliding direction (refer FIG. 1D).
In addition, this area includes (3) a ring-shaped area around the dowel section (see FIGS. 1E and 7), and (4) covering at least the inner hole width in the plate width direction in accordance with the outer shape of the width direction end of the plate. The region (see FIG. 1C), or (5) the entire region in the vicinity of the dowel portion (the hatched portion in FIG. 1A (a)).
In the case of conditions where cracks are likely to occur in the vicinity of the inner hole, in order to distribute the surface pressure more evenly while avoiding concentrating on the local area while concentrating the surface pressure in the vicinity of the inner hole, (4) Or it is preferable to select the area | region of (5).

In addition, when installing in the area | region of the said dowel part vicinity in the outermost vicinity of a plate sliding direction, it is preferable to install so that it may continue from the external position of a dowel part at least.

In addition, there is another sheet-like heat-resistant material (for example, the ceramic sheet 4 in FIG. 1A) or an iron plate (for example, the iron plate 5 in FIG. 1A) on the back surface of the plate. The sheet-like heat-resistant material of the present invention is placed on the surface of “other sheet-like heat-resistant material” or, if not, the height of “other sheet-like heat-resistant material” is higher than the height. Install to be.

In addition to installing these sheet-like heat-resistant materials, as a second means, the thickness of the plate body in the area where the sheet-like heat-resistant material is installed can be made thicker than other areas.
In this case, a sheet-like heat-resistant material or a ceramic sheet (other sheet-like heat-resistant material) may be further affixed to the region where the thickness of the main body is thicker than other regions, but it is not necessary to affix it. Good. In order to suppress the stress dispersion effect when the surface pressure is applied or to suppress cracking, it is preferable that one or more layers of these sheets are attached.
In order to make the thickness of the plate body as the second means thicker than other regions, when molding the plate, the height of the molding surface of the mold is changed according to the thickness. The method of processing etc. can be taken.

Here, when there is another contractible sheet-like heat-resistant material and the sheet-like heat-resistant material of the present invention is placed on the surface thereof, the other contractible sheet-like heat-resistant material is used. However, if the sheet is shrunk to the maximum contractible allowance in the entire region, the stacked sheet-like heat-resistant material of the present invention protrudes from the periphery of other heat-shrinkable sheet-like heat-resistant materials. However, when the installation part of the stacked sheet-like heat-resistant material of the present invention is small, the surrounding area does not shrink completely and the crimping force is distributed over a wide area so that the stacked sheet-shaped heat-resistant material of the present invention protrudes. There is a possibility of diminishing the effects of. Therefore, it is more preferable that the thickness of the stacked sheet-shaped heat-resistant material of the present invention is larger than the contractible allowance of other sheet-shaped heat-resistant materials.

In the present invention, as the sheet-like heat-resistant material, either a sheet obtained by molding a fibrous inorganic material, a plate-like metallic material, or a multilayer structure thereof can be used. However, in order to correct the warp and suppress the generation of gaps, it is preferable that the material is not shrinkable or as small as possible. For example, at least the sheet-like heat-resistant material during operation is installed. It is preferably a single-layer or multi-layer structure such as a refractory or a metal having heat resistance enough to remain at a temperature higher than the expected temperature at the place.

By installing this sheet-like heat-resistant material or by increasing the thickness of the main body, the thickness of this target area protrudes in the vertical direction from the other flat parts on the back of the plate. Optimization may be made according to the characteristics of the heat-resistant material, the characteristics of other sheet-shaped heat-resistant materials when stacked, or individual conditions such as operating conditions such as temperature and time. With regard to the thickness of the sheet-like heat-resistant material, the present inventors firstly stated that the maximum bending allowance due to deformation is about 0.3 mm when the surface pressure is maximum, and decreases to about 0 when the surface pressure decreases. Depending on the deformation of the hardware on the device side, the set state, etc., the bending allowance may be further increased, and the total bending of the upper and lower plates may be about 1.6 mm. This was confirmed by simulation and actual operation under the same conditions as in the following experiment. Note that “total” is the sum of the deflection dimensions of each of a plurality of plates (for example, upper and lower plates), in other words, even if the thicknesses of the thickened portions of each plate are different. This means the sum of the increased thickness (thickness protruding) of the thick region of the plate.
In other words, when the deformation or set state of one individual plate is different and the degree of bending is also different, the gap between the plates can be adjusted by adjusting the degree of thickness increase (projecting thickness) on the other plate. It is possible to suppress or prevent the occurrence of.

In addition, in a general structure in which another sheet-like heat-resistant material having, for example, about 20% contractibility and an iron plate having almost no contractibility are present on the surface of the plate, the sheet-shaped heat-resistant material of the present invention is used. It was confirmed from the experimental results (described later) that it is assumed that the sheet-shaped heat-resistant materials are installed in a stacked manner, and that the minimum thickness of the sheet-like heat-resistant material is preferably about 0.1 mm or more.

On the other hand, in the same experiment, it was confirmed that the maximum thickness of the sheet-like heat-resistant material should be about 1.6 mm or less. In other words, this 1.6mm thickness is placed on another sheet of about 3mm thickness (approx. 0.5mm shrinkable) and an iron plate of about 0.24mm thickness on top of it to install a sheet-like heat-resistant material According to the experimental results, the thickness is considered to be the limit thickness where cracks in the plate width direction are not expected to occur. Under the conditions in this case, if the thickness exceeds 1.6 mm, a gap is likely to be formed at both ends in the sliding direction, like a “lever” where the plate is the outermost sheet-like heat-resistant material. That is, there is a possibility that the convex portion becomes excessive and an abnormal crack as shown in FIG. 6 occurs in the width direction of the plate. However, the thickness exceeds 1.6 mm under different conditions, for example, when the deformation of the metal frame is large, the installation is such that the sliding surface direction of the plate is greatly inclined, or the plate thickness is large. It may also be acceptable.

These thick areas only need to be relatively thick relative to the other areas. Therefore, even when other sheet-like heat-resistant materials are applied, the thicknesses of the thick areas and the other areas are different. Are the same, the relative thickness may be adjusted as described above without considering the thickness of the sheet-like heat-resistant material or the like. However, the thickness of the sheet-like heat-resistant material, etc., and the contractibility may be different between the thickening area and other areas. In such a case, the thickness should be adjusted within the range of 0.1 mm to 1.6 mm. That's fine.
Further, the degree of increase in thickness of the region to be thickened may be adjusted according to the size of the contractibility of the sheet-like heat-resistant material or the like, that is, the degree of increase in thickness may be increased as the contractibility increases.

In the examples of FIGS. 1A to 1E, the outer shape of the inner hole 1 and the dowel portion are both circular, but these shapes are not limited to a circular shape, and may be, for example, an elliptical shape.

Examples of the present invention will be described based on experimental results.

[Experiment A]
Experimental Example A is an experimental example in which the state related to the gap between the sliding surfaces of the plates in the state of the prior art, that is, the “sheet-like heat-resistant material” of the present invention is not installed, is observed by the difference in pressure applied between the sliding surfaces. It is.

In the experiment, as shown in the image in Fig. 4, an actual sliding nozzle device composed of three plates, upper, middle, and lower, was used, and a sensor sheet was installed between the sliding surfaces of the plates to change the surface pressure. In addition, the difference in surface pressure by region was measured.

The experimental conditions such as shape and pressure are as follows.
The shape of the plate is as follows: long side (length in sliding direction): about 414 mm, short side (length in the direction perpendicular to the long side (width direction)): about 209 mm, plane part thickness: about 35 mm (upper and lower plates) ), About 40 mm (medium plate), inner hole diameter: 75 mmφ, the material of the plate is selected as a refractory of about 75% by mass of Al ₂ O ₃ , about 10% by mass of ZrO _{2 and} about 5% by mass of carbon, Its physical properties are a sonic elastic modulus of 40 GPa and a room temperature bending strength of 13 MPa. The plate was fixed by holding metal from the four corners of the edge and fixing bolts to a tightening torque of 20 N · m, and the surface pressure was applied stepwise up to a total load of less than 6 tf.

This experiment was conducted at room temperature. The operation, that is, the actual use, and the intrusion between the sliding surfaces occurs under conditions where, for example, molten steel with a temperature of about 1500 ° C passes through the inner hole. (Because the refractory expands as the temperature rises, it does not bend in the opposite direction or the degree of bending does not decrease even if the temperature rises). The experimental results at room temperature can be used as a means of evaluating trends in actual operation without reducing the gap between moving surfaces.

FIG. 5 (a) shows the measurement result of the pressure distribution detected by the sensor sheet as seen from the sliding surface of the plate, and FIG. 5 (b) shows the surface pressure at each measurement point with the number in FIG. 5 (a). Shows the relationship between magnitude and pressure.

As shown in FIG. 5B, it can be seen that the pressure near the center is lower than the outside, and the difference increases proportionally as the surface pressure increases. That is, it is suggested that the vicinity of the center centering on the inner hole increases the total load but does not contribute to the increase of the surface pressure. Since the inner hole portion is a space and exists in the vicinity of the center, it can be understood that it is the most easily deformed place in the plate as a structure.

[Experiment B]
Experimental Example B is an example of observing the effect on the pressure between the sliding surfaces when the “sheet-like heat insulating material” of the present invention is installed around the dowels of both the upper and lower plates. In the experiment, as shown in the image in Fig. 7, an actual sliding nozzle device composed of two upper and lower plates was used, and pressure-sensitive paper was placed between the sliding surfaces of the plates to add a constant surface pressure (6 tf). The pressure states were compared.
Experimental conditions such as shape are the same as in Experimental Example A.

In Comparative Example 1, another sheet having a contraction allowance of about 0.5 mm (20%) and a thickness of about 3 mm and an iron plate of 0.24 mm are placed on almost the entire back surface of the plate excluding the dowel portion. This is an example in which the “sheet-like heat insulating material” of the present invention is not installed only around the dowel portion.

In Example 1, the other sheet and the 0.24 mm iron plate on the other sheet were installed on almost the entire back surface of the plate excluding the dowel part (this part is the same as Comparative Example 1). This is an example in which a ring-shaped 0.24 mm iron plate with a diameter of 190 mmφ is installed in a circular area centered on the inner hole (see FIG. 7A).
Example 2 is an example in which an iron plate having a thickness of 0.5 mm as a “sheet-like heat insulating material” is installed in the same structure and region as Example 1 (see FIG. 7A).

The result of the experiment is shown in FIG. FIG. 7B is a diagram (photograph) showing the surface pressure distribution that appears on the pressure-sensitive paper. The darker the color, the higher the pressure, and the lighter the color, the lower the pressure.
In both examples, the pressure tended to decrease as the area approached the inner hole, but the color of the example was darker than the comparative example as a whole. The contour of the inner hole can be observed along with the tendency to be deep. It can also be seen that Example 2 was darker than Example 1, that is, the pressure was higher. From this result, it can be seen that in both Examples 1 and 2, higher pressure was applied around the inner hole, that is, near the dowel, than in the comparative example, and there was no gap.

[Experiment C]
Experimental Example C is the actual operation in Comparative Example 1 of Example B and Example 1 (0.24 mm (0.48 mm in total) on both upper and lower plates), Example 2 (both upper and lower plates) 0.5 mm (1 mm in total), and Example 3 (0.1 mm (0.2 mm in total) on both the upper and lower plates) and Example 4 with different thickness of the iron plate, Example 4 ( Between the sliding surfaces when 0.8 mm (1.6 mm total iron plate) on both the upper and lower plates and Example 5 (0.1 mm iron plate only on one upper and lower plates) are installed around the dowel It is the example which observed the bullion insertion suppression effect of.
The experimental conditions such as the shape are the same as in Experimental Examples A and B.
In all of Examples 1, Example 2, Example 3, Example 4, and Example 5, there was no metal bar, and no significant or unusual damage was caused to the plate.
In Comparative Example 1, the bullion invaded a part of the periphery of the dowel between the sliding surfaces.

1 Inner hole 2a Convex part (part of a dowel part)
2b The part where other nozzles such as the upper nozzle and lower nozzle that fit into the convex part come into contact with the back of the plate (part of the dowel part)
3 Sheet-like heat-resistant material 4 Ceramic sheet (other sheet-like heat-resistant material)
5 Iron plate (other sheet-like heat-resistant materials)
6 Hoop 10 Fixed metal frame 11 Slide metal frame 12 Plate body

Claims

The length of the surface opposite to the sliding surface (hereinafter referred to as “rear surface”) is twice the length from the short side end to the center of the inner hole starting from the short side end. The sheet-like heat-resistant material is protruded in the thickness direction of the plate from the other area of the back surface in part or all of the area near the dowel around the inner hole that is within the range to the scale side position. Is installed or has an area where the plate body is thicker than other areas,
The area where the sheet-like heat-resistant material is installed or the thickness of the plate body is thicker than other areas is in contact with at least a part of the metal frame of the sliding nozzle device for fixing the back side of the plate. The sliding nozzle device plate.
The said plate is any one or both of the upper plate attached in contact with the fixed metal frame by the side of the molten steel container of a sliding nozzle apparatus, and the lower plate attached in contact with the downward slide metal frame. A plate for a sliding nozzle device as described in 1.
The sheet-like heat-resistant material is either a sheet obtained by molding a fibrous inorganic material or a plate-like metallic material, or a multilayer structure thereof, according to any one of claims 1 and 2. Plate for a sliding nozzle device as described.
The thickness of the plate body thicker than the other region or the thickness of the sheet-like heat-resistant material protruding in the thickness direction of the plate from the other region is 0.1 mm or more and 1.6 mm or less. The plate for a sliding nozzle device according to any one of claims 1 to 3.
The sheet-like heat-resistant material is either a sheet formed mainly from a fibrous inorganic material, a plate-like metallic material, or the surface of another sheet-like heat-resistant material that is a multilayer structure thereof. The plate for a sliding nozzle device according to any one of claims 1 to 4, which is installed.