JPS5964153A - Construction of cooling type slide valve plate for controlling flow rate of molten steel - Google Patents

Abstract

PURPOSE:To extend the service life of a slide valve plate by covering the outside surface of a metallic body and a metal with a refractory ceramic and cooling the body. CONSTITUTION:A plate body 10 is made of a metal in a hollow construction permitting internal cooling. Covering 11 of a refractory ceramic on the outside surface of the body 10 is accomplished by fixing a refractory ceramic body formed separately by using various kinds of pressing, casting, etc. onto the outside surface of the body by means of an org. adhesive agent such as an epoxy-, cyano- or the like adhesive agent. The amt. of the ceramic to be used is reduced by the above-mentioned method, whereby the decrease in strength of the ceramic at a high temp is prevented by the cooling effect, the high resistance to erosion and wear by molten steel is obtd. and the expansion in the size of the hole for passing the molten steel is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a slide plate for controlling a molten steel flow area.

In recent years, the slide valve system has been widely used for controlling the flow of molten copper in ladle and tundish for steelmaking. Also, attempts have been made to use it in converters and the like.

A slide valve type 4Ft structure is shown in Figures 1 and 2. Fixed plate ge and sliding plate 2 in Figure 1
The P7 moving surface 3 of the two plates is precisely polished and is sufficiently smooth to form a smooth surface. The lower sliding plate of these two plates! can be slid in the left and right directions in FIGS. 1 and 2, thereby changing the cross-sectional area of the molten steel passage hole and adjusting the drunkenness. In order to satisfy such Sugihashi ability, defects such as cracks, chips, abrasion, erosion, etc. must not occur in the hole through which the molten steel passes through the plate. In addition, the tilting surface must have sufficient smoothness to prevent molten steel from entering through the molten steel passage section.

When molten steel is charged into the molten steel container, the slide valve is in the closed state as shown in FIG. At this time, the molten steel passage hole of the fixed plate and the 0. The E nozzle hole is filled with sand-f1. Therefore, one plate is in direct contact with molten steel9j! No.

Next is the plate! Due to the movement of the molten steel passage hole -
It will be in the state shown in Figure 1, where it is open. At this time, the filling sand falls as the molten steel is piled up, and the next moment, the molten steel at the same temperature flows at high speed through the molten pool and the first passage hole. That is, this instant molten copper connection] 1ifi
Hole v; 1 undergoes sudden thermal shock. Furthermore, while the melt I passes through, it is subjected to wear and erosion due to the melt flow.

After the solubilized h1° flows out from the h'i jpl container, slide the sliding sillage) j! 1b is melted (1 tracing hole λ is closed) and returned to the state shown in Fig. Since the plate slides in contact with the plate, it is subjected to thermal shock on the very surface.After the same operation is repeated λ~g times, the fixed plate and the sliding plate are placed in a consignment.

In the figure, l indicates an upper nozzle and /I indicates a lower nozzle.

The process until a conventional slide valve plate is discarded is as follows.

Melting: 'l, Is there an initial V in the IIfI hole? - Due to the thermal shock received, a radial 1+ to 6 is generated as shown in FIG. This crack grows continuously with repeated use and spreads throughout the plate. In addition, during the passage of the molten can, it is subjected to wear and erosion by the molten steel flow, and the passage hole of the bath 6$7 expands, and the cracks caused by the aforementioned thermal shock induce peeling of the edge part 7, causing the hole diameter to expand. Sukezun). In this condition, the plate loses its ability to accurately control flow, and is therefore discarded.

On the other hand, on the sliding surface of the sliding plate 7911, surface layer peeling ♂ occurs at 4 Kp due to the heat f117i impact on the sliding surface, resulting in loss of smoothness.

This is facilitated by the growth of cracks generated in the pore-extinguishing part. Printing that has lost sufficient smoothness; iJI+
Even when the surface is pressed under high pressure, it becomes a hole through which the molten steel passes!
Jin, who can stop people, is no longer able to do so and is discarded.

Conventional slide knob type plate part (Rini is generally A), 03 quality, Mroy (, A/,, o3-0
Kaa Rui li MfO-0: A large press molded product such as Lu is used, but it is not enough to add 61.

Even better than conventional refractories, ml heat impact resistance and wear resistance are 1'1.
It is IIJ's opinion that a long service life can be obtained by making a plate with ceramics that have excellent corrosion resistance and one-sided heat fit. However, in general, side thermal shock resistance and corrosion resistance are contradictory characteristics. 116 class i, which has both of these characteristics.
Single-layer ceramics are not put into practical use because they are extremely expensive.

A conventional slide plate is made of a single piece (one brick) made of a press-molded refractory material, and one plate is homogeneous throughout. For this reason, the following disadvantages can be cited. Firstly, damage to the holes and sliding surfaces is the direct cause of plate scrapping. In other words, damage to a small portion of the plate that comes into contact with the molten steel determines the service life of the entire plate. Therefore, the majority of the plate that comes into contact with the molten steel is left undamaged. This creates a lot of waste and hinders the use of high-grade refractory ceramics.

Secondly, since the entire plate is homogeneous, cracks generated in the molten steel passage holes grow continuously.

Third, the molten steel passing hole, sliding surface, and other parts are all press-formed in one piece, even though the damage types p It is difficult to apply it to the part 1#.

The present invention relates to a structure of a main body made of gold N, a refractory ceramic covering the entire outer surface of the metal member, and a slide valve plate that does not cool the main body.

f! rλI1. 1+21 shows an example of the configuration of the present invention.

The plate body 10 is made of metal and has a shape 11J' similar to that of the conventional plate.
1q construction and Z. The outer surface of the metal body 10 is coated with fire-resistant ceramic by applying an organic adhesive such as epoxy or cyano to a separately prepared fire-resistant ceramic body using press molding, cast molding, or the like. It may be fixed with an inorganic entrainer such as alkali silicate, alkali phosphoric acid, or alkali borate.

Furthermore, it is also possible to apply tU directly to the metal body using plasma spraying, flame spraying, chemical vapor deposition, or the like.

The slide valve plate of the present invention obtained in this way can reduce the amount of ceramic used, and the water cooling effect prevents the ceramic strength from decreasing even at high temperatures, making it resistant to erosion and abrasion caused by solutionization. Excellent molten steel JIn hole diameter] Prevents large pores. 1. For the same reason, smoothness at 4°Nlh ig+i is maintained.

The refractory ceramic for covering 11 is A t! 03, M
? 0, 8 i 02Or203, Zr01.
0aOTi01 '4? In addition to the oxide of 8i1N4゜k
If the ceramic has sufficient thermal shock resistance, hard abrasion resistance, and corrosion resistance against molten copper, such as nitrides such as tN, RN, carbides such as 8i0.1340, WO, etc., some or -2 or more of the above may be used. A ceramic composite may also be used.

However, one or more layers may be used to eliminate or reduce differences in physical properties, such as differences in coefficient of thermal expansion, between the metallic body and the refractory ceramic. In this case, each layer C' may be made of ceramics, or may be made of materials that do not necessarily have fire resistance, such as gold (t''4, -remet, low melting point 1, 1, 2 compounds, etc.). The thickness of the refractory ceramic may be used to determine the properties of the coated ceramic, such as thermal conductivity, thermal expansion coefficient, porosity, etc.
It should be determined taking into account the air permeability, hot strength 1 elasticity modulus, etc., but on the sliding surface it is approximately Q, -2~/ja,
Approximately O0j to 4'('fl + N is good for the passage hole. This is because if the thickness of the coating is too thin, the characteristics of the refractory ceramics cannot be fully demonstrated, and the cooling of the metal body is excessive at the contact part with the molten copper. This may cause some of the molten steel to solidify.

If the surface thickness is too thick, high-grade ceramics will be expensive, and the water-cooling effect will prevent the sliding surface from becoming rough, and the water-cooling effect will prevent melting and peeling of the TJ perforation area. This is not a good idea as the effect of preventing hole diameter expansion will be very small.

The target range is the entire surface or the entire surface of the metal body.
Even if it is difficult, at least the area exposed to high temperature as shown in Figure V, that is, the molten steel passage hole! and sliding surface 1d
, 11ii is preferably covered with 4゛-1 of refractory ceramic.

The metal body is preferably cooled by using water, oil, air, nitrogen gas, or the like as a refrigerant and circulating it inside the plate body.

Example: The plate body is made of stainless steel, and the soluble passage hole is made of IO-limited Si 3 N4 ceramic sintered body and Z r 0
1 Ceramic Akatsuki concretion is used and affirmed with an inorganic adhesive, (v
・On the 11th surface, A Lx Os Thl'l fire material was thermally sprayed to a thickness of 4 m using the plasma spraying method, and in the same way, Zr3i04 hard metal was spray molded on the sliding surface using the plasma spraying method. 4'1? A comparative test was conducted between a slide nozzle plate thermally sprayed to a W thickness and an A-1,03J plate made using the conventional method. Water was used to cool the plate body of the present invention.

Try! ! iFQ t, heat f! R7'J) test and Inika food test were conducted.

Nekshō 9 exams 1~i! 6. A flame caused by purple acetylene was heated so that the surface temperature of the ceramic was 1700℃.
jJII 1/% Plate sliding surface and melting (, (
One operation consisted of heating the passage hole portion for 5 minutes and allowing it to cool for 30 minutes. This operation was repeated for 1 J, and a comparison was made based on the number of times the covered ceramics and comparative bricks were lit until 46 cracks appeared, and the number of times they were lit in the pit where peeling was observed in some areas.

The mortality test was stopped after 120 repetitions.

Erosion tests were carried out using an induction furnace /l! ;0℃-HiroFf6'
11.4 holes in front of the molten steel under the condition of 1 lil f erosion due to iH)? 1 was compared. Table 1 shows the quality and test results of the coated ceramic of the slide plate according to the present invention and the comparative ht, o, and quality plates, which were 5 pins on the top side after the test.
Shown below.

It was found that the Iy1 product of the present invention is superior in terms of heat resistance and impact resistance compared to conventional products.

JP-A-59-64153 (4) The above results (1) Since the use of ceramics +11 is less than about -11 compared to the conventional plate, a high-grade surface monolithic ceramic 4th material was applied to the sliding knob plate. It is possible to do so (i1).

(2) A nail stand 24 was formed in the ceramic covered part, and the hole 18 also cracked.1. Since it grows only near the boundary with the metal ri of the wood, damage caused by peeling can be reduced.

(3) Since different optimum ceramics can be selected and applied to each part of the plate, the ceramics of each part can be used effectively.

It has been found that due to the action and effect of soil ft, it can be expected to be used more than three times as much as the fly 1:' valve plate from lyfe.

[Brief explanation of the drawing]

Kg 7 Figure to Kasu 3 Figure d are related to the conventional slide valve, Figure 1 is a schematic diagram of y, ;, 4 section Mi when the slide valve is opened, Figure 2 is also a slide valve of 12
) A schematic vertical cross-sectional view when the pulp hole is opened, Figure 3 is a schematic diagram showing the damage state of the slide pulp plate, and Figure 3 is a schematic diagram of the structure of the slide pulp plate according to the present invention l1lJ. FIG. 5 is a plan view of an example showing the main
-Figure■-■ Cross-sectional view, io←), Hollow plate body with metal storage, //Made with refractory ceramics. Figure 1 Figure 4 Figure 5 Procedural amendment (voluntary) October 27, 1988 Mr. Commissioner of the Japan Patent Office ■, Indication of the case 1982 Patent Application No. 146944 2, Title of the invention 3, Person making the amendment Relationship to the incident Patent applicant Location: 2-2-1 Otemachi, Chiyoda-ku, Tokyo (1
9γ) Name Shinagawa White Brick Co., Ltd. (6645) Name
Eight books 1) Shimoji 5, Detailed explanation column of the invention in the positive subject specification and Drawing 6, Contents of amendment (1) Specification No. 6 Negative - Line 5 from line 1 "Water cooling" to 1
"Cooling" is corrected. (2) Change [Ca0TiO,J in the second line of the same gt page to “C
ab. Corrected with TiO, J, and changed “1 Metallicity” in the 7th line to “Made of metal”
and correct it. (3) "Water cooling" on page 8, line 3 is defined as "cooling." (4) Add the code ``d motion [i 3'' to Figures 1 and 2 (please enter the information as marked in red on the attached drawing copy).

Claims (1)

[Claims] (1) Slide valve plate structure for cooling-type hot iron ryuda control 1 consisting of a metal body, refractory ceramics covering the outer surface of the metal, and cooling the body (-2) 1rj-1 human-made ceramic coating A slide valve plate structure for cooling-type molten steel flow rate control according to claim 1, wherein the slide valve plate structure is applied to at least the sliding surface and the inner tail surface of the molten steel passage hole.