JP2571974Y2 - Pouring nozzle in continuous casting facility with moving mold wall - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pouring nozzle in a continuous casting facility having a moving mold wall.

[0002]

2. Description of the Related Art Conventionally, as this type of pouring nozzle device, for example, there is one shown in FIG. That is, 51 is a mold roll (hereinafter simply referred to as a roll) arranged in parallel with each other, and a position between the two rolls 51 is a
51 and a pair of weirs arranged in contact with both end surfaces of both rolls 51
In cooperation with 52, a molten steel reservoir 53 is formed. Numeral 54 denotes a metal surface protection cover for covering the molten steel surface 56, and the metal surface protection cover 54 is supported between the two dams 52. On both sides of the lower surface of the molten surface protection cover 54, immersion walls 55 are protruded in parallel with the axes of the rolls 51, and the lower portions of the immersion walls 55 are immersed in molten steel in the molten steel reservoir 53. Have been. Molten steel surface 56
Above, a space portion 57 formed between the two immersion wall portions 55 and the lower surface of the central portion of the molten metal surface protection cover 54 is formed.

[0003] Reference numeral 59 denotes a pouring nozzle for guiding molten steel from the tundish 60 into the molten steel reservoir 53, and is provided to hang down from the tundish 60. The lower end of the pouring nozzle 59 is inserted from above into a nozzle insertion hole 61 formed in the center of the molten metal surface protection cover 54, and protrudes from the space 57 below the molten metal surface protection cover 54. A discharge port 64 is formed in the lower end side surface of the pouring nozzle 59. An inert gas supply hole 62 communicating with the space 57 is formed in the hot water surface protection cover 54, and the inert gas supply hole 62 is provided outside via an inert gas supply pipe 63. Connected to an inert gas supply source.

According to this, at the time of starting the casting, first, the molten metal surface protection cover 54 is attached between both dam bodies 52 so that the gap between the molten metal surface protection cover 54 and the two rolls 51 becomes a predetermined gap S3. set. Then, after the tundish 60 is moved onto both rolls 51, the tundish 60 is lowered, and the lower end of the pouring nozzle 59 is inserted into the nozzle insertion hole 61 of the metal surface protection cover 54 from above. Then, the molten steel flows from the tundish 60 into the pouring nozzle 59, and both rolls 51 are rotated. Thereby, the molten steel is discharged from the discharge port 64 to the molten steel reservoir 53 through the pouring nozzle 59, and is cast by the two rolls 51. At this time, by supplying an inert gas from the inert gas supply hole 62 into the space 57, air is prevented from flowing into the space 57 and oxidation of the molten steel surface 56 is prevented.

[0005]

However, according to the above-mentioned conventional type, the tundish 60 is moved and the pouring nozzle 59 is moved.
Into the nozzle insertion hole 61 of the surface protection cover 54,
The diameter of the nozzle insertion hole 61 had to be considerably larger than the diameter of the pouring nozzle 59. Therefore, a large gap S4 is formed between the inner peripheral surface of the nozzle insertion hole 61 and the outer peripheral surface of the pouring nozzle 59, and in order to prevent air from flowing into the space 57 from the gap S4, an Active gas supply hole 62
Has to supply a large amount of inert gas.

An object of the present invention is to solve the above-mentioned problem, and an object of the present invention is to provide a pouring nozzle capable of sealing a gap between the nozzle insertion hole and the pouring nozzle before starting casting. .

[0007]

In order to solve the above-mentioned problems, a pouring nozzle in a continuous casting facility having a moving mold wall according to the present invention comprises a pair of moving mold walls arranged in parallel with each other from a tundish. A pouring nozzle for injecting molten steel into a molten steel reservoir formed between the weir bodies provided at both ends of the mold wall, and a pouring surface protection cover for covering the molten steel surface.
Bar support fixed in position between the two weirs body, divides the pouring nozzle and the lower nozzle having a top nozzle and the discharge port, mounting the top nozzle on the tundish, which is formed on the melt surface protection cover nozzle the insertion hole, the mounting by inserting the bottom nozzle is provided with a sealing member for sealing a gap between the lower nozzle and the nozzle insertion hole, the upper to the lower end of the upper nozzle
The upper flange is formed on the outer periphery of the lower surface of this upper flange.
Forming an outwardly facing upper inclined surface, the upper end of the lower nozzle
A lower flange is formed on the lower flange, and an upper
The flange forms a fitting groove that can fit freely, and the outer circumference of this fitting groove
Form a lower inclined surface that can contact the upper inclined surface
By fitting the upper flange into the fitting groove
Te, in which the lower end of the upper nozzle was freely communicated disconnect the upper end of the lower nozzle fitted with the molten metal surface protection cover.

[0008]

According to the above construction, at the start of casting, the lower nozzle is previously inserted and attached to the nozzle insertion hole of the molten metal surface protection cover. Thereby, the gap between the outer peripheral surface of the lower nozzle and the inner peripheral surface of the nozzle insertion hole is sealed by the sealant. Then, set the surface protection cover, move the tundish, and fit the upper flange of the upper nozzle into the fitting groove of the lower nozzle.
And the lower end of the upper nozzle communicates with the upper end of the lower nozzle. Then, by flowing the molten steel from the tundish, the molten steel is discharged from the upper nozzle through the lower nozzle to the molten steel reservoir. After completion of casting, the upper nozzle is separated from the lower nozzle by moving the tundish.

As described above, the gap between the outer peripheral surface of the lower nozzle and the inner peripheral surface of the nozzle insertion hole is sealed by the sealing material by attaching the lower nozzle to the molten surface protection cover in advance. It becomes difficult for air to flow between the molten steel surface protection cover and the molten steel surface through the gap, and therefore,
By supplying a small amount of inert gas between the molten steel surface protection cover and the molten steel surface, it is possible to prevent air from flowing in.
When fitting the upper flange into the fitting groove, the upper inclined surface
Because it is guided against the lower slope, the upper flange is
It is fitted into the fitting groove accurately without shifting in the lateral direction.
Causes the upper and lower nozzles to shift laterally.
It is joined exactly.

In addition, since the vicinity of the discharge hole is most severely damaged at the time of casting, only the lower nozzle can be made of a material having excellent erosion resistance. Only the lower nozzle needs to be replaced.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS. Reference numeral 1 denotes a mold roll (hereinafter, simply referred to as a roll) which is a kind of a moving mold wall disposed in parallel with each other.
And a pair of weir bodies (also referred to as short-side weirs, only one of which is shown) 2 arranged in contact with both end surfaces of both rolls 1 to form a molten steel reservoir 3. Above both rolls 1, there is provided a tundish 4 which is movable in the horizontal and vertical directions, and a pouring nozzle 5 for guiding molten steel from the tundish 4 into the molten steel reservoir 3 is provided in a hanging manner. Reference numeral 6 denotes a metal surface protection cover for covering the surface of the molten steel in the molten steel reservoir 3.

The pouring nozzle 5 is divided into an upper nozzle 5a and a lower nozzle 5b, and the upper nozzle 5a is attached to the tundish 4. That is, the tundish nozzle brick 9 is provided on the bottom plate 8 of the tundish 4, and the upper surface of the upper nozzle 5 a is in contact with the lower surface of the tundish nozzle brick 9 via the sliding nozzle 10. The upper end of the upper nozzle 5a is formed as an engaging flange 11. A nozzle holding plate 12 is externally fitted to the upper nozzle 5a, and the nozzle holding plate 12 is attached and fixed by bolts and nuts 13 vertically provided on the tundish 4. As a result, the fitting flange 11 of the upper nozzle 5a is pressed and fixed to the lower surface side of the tundish nozzle brick 9 via the sliding nozzle 10. The tundish nozzle brick 9 is provided with a tundish nozzle hole 15 communicating with the upper nozzle hole 14 of the upper nozzle 5a. The sliding nozzle 10 narrows the flow path between the nozzle holes 14 and 15 to adjust the flow rate of the molten steel. An upper flange 17 is formed at the lower end of the upper nozzle 5a. The outer peripheral edge of the lower surface 18 of the upper flange 17 is formed as an outwardly inclined upper surface 19.

The lower nozzle 5b is provided on the surface protection cover 6 side. That is, a lower flange 22 is formed at the upper end of the lower nozzle 5b, and a fitting groove 23 into which the lower end of the upper flange 17 can be fitted is formed in the lower flange 22. The bottom surface 24 of this fitting groove 23 is an upper flange
An outer peripheral surface of the fitting groove 23 is formed as a lower inclined surface 25 that is freely abuttable on the upper inclined surface 19 of the upper flange 17. Reference numeral 26 denotes a sealing material using asbestos, mortar, or the like, which is sandwiched between the lower surface 18 of the upper flange 17 and the bottom surface 24 of the lower flange 22 to seal with the outside. A lower nozzle hole 27 having a diameter larger than that of the upper nozzle hole 14 is formed in the lower nozzle 5b, and a discharge port 28 is formed in a lower end side surface of the lower nozzle 5b. The lower nozzle 5
The lower end of b is closed.

The metal surface protection cover 6 is mounted with both ends supported between the two weirs 2. This hot water surface protection cover 6
At both ends of the upper surface, a frame body 32 including a frame 30 extending in the axial direction of the roll 1 and a plurality of frames 31 connected between the two frames 30 is provided.

At both ends of the lower surface of the surface protection cover 6, immersion walls 33 are projected in parallel with the axes of the rolls 1, and the lower portions of the immersion walls 33 are molten steel in the molten steel reservoir 3. Is immersed in. A gap S1 is provided between the immersion wall 33 and the roll 1.
Is provided. On the molten steel surface 34, there is a space formed between the two immersion walls 33 and the center of the lower surface of the surface protection cover 6.
35 are formed.

A nozzle insertion hole 37 communicating with the space 35 is formed in the center of the hot water surface protection cover 6. Above the nozzle insertion hole 37, a lower nozzle support 39 is provided. The lower nozzle support 39 has substantially the same inner diameter as the nozzle insertion hole 37 and has a cylindrical portion 39a fitted into the frame body 32, and is provided continuously from the upper end of the cylindrical portion 39a to the outer side.
And a disc portion 39b supported on the upper surface of the disc 32. And
By inserting the lower nozzle 5b from above into the lower nozzle support 39 and the nozzle insertion hole 37, the lower flange 22
Is received and supported by the lower nozzle support 39, so that the lower nozzle 5b is attached to the molten metal surface protection cover 6. The outer peripheral surface of the lower nozzle 5b and the lower nozzle support 39
And a gap S2 between the inner peripheral surface of the nozzle insertion hole 37 and the sealing material
Sealed by 40.

In order to prevent oxidation of the molten steel surface 34, an inert gas supply hole communicating with the space 35 is provided in the surface protection cover 6.
The inert gas supply hole 42 is formed through an inert gas supply pipe 43 and connected to an inert gas supply source provided outside. Further, an inert gas supply nozzle 44 for blowing an inert gas into a gap S1 between the roll 1 and the immersion wall 33 is disposed.

The operation of the above configuration will be described below.
At the start of casting, the lower nozzle 5b is inserted and attached to the nozzle insertion hole 37 of the surface protection cover 6 in advance. As a result, the gap S2 between the outer peripheral surface of the lower nozzle 5b and the inner peripheral surface of the nozzle insertion hole 37 is sealed by the sealing material 40. Thereafter, the surface protection cover 6 is set between the two weirs 2, and a gap S 1 having a predetermined size is provided between the immersion wall 33 and the roll 1. Then, after the tundish 4 is moved laterally and positioned above the lower nozzle 5b, the tundish 4 is moved downward to fit the lower end of the upper flange 17 of the upper nozzle 5a into the fitting groove 23 of the lower nozzle 5b. And press it. As a result, the sealing material 26 comes into close contact with the lower surface 18 of the upper flange 17 and the bottom surface 24 of the lower flange 22, and the fitting portion between the upper nozzle 5a and the lower nozzle 5b is sealed.

Then, the molten steel flows from the tundish 4 and both rolls 1 are rotated. As a result, the molten steel flows from the upper nozzle 5a to the molten steel reservoir 3 via the lower nozzle 5b.
And cast by both rolls 1. During casting,
In order to prevent oxidation of the molten steel surface 34, an inert gas supply hole
An inert gas (nitrogen gas, argon gas, or the like) is supplied from 42 to the space 35, and an inert gas is supplied from the inert gas supply nozzle 44 to the gap S1. Then, after the casting is completed, the upper nozzle 5a is separated upward from the lower nozzle 5b by moving the tundish 4 upward.

As described above, by attaching the lower nozzle 5b to the surface protection cover 6 in advance, the lower nozzle 5b
Since the gap S2 between the outer peripheral surface of the nozzle b and the inner peripheral surface of the nozzle insertion hole 37 is sealed by the sealing material 40, it is difficult for air to flow into the space 35 through the gap S2. By supplying gas from the inert gas supply hole 42 to the space 35, it is possible to prevent air from flowing into the space 35. In addition, move tundish 4 to
When the flange 17 is fitted into the fitting groove 23, the upper inclined surface 19 is tilted downward.
Since it is guided in contact with the slope 25, the upper flange 17
Is accurately fitted in the fitting groove 23 without shifting in the lateral direction,
As a result, the upper nozzle 5a and the lower nozzle 5b move sideways.
It is accurately joined without shifting.

Further, since the vicinity of the discharge port 28 is most severely damaged during casting, only the lower nozzle 5b can be made of a material having excellent erosion resistance.
If the vicinity is damaged, only the lower nozzle 5b needs to be replaced.

Further, the lower nozzle 5b is
Then, by setting the molten metal surface protection cover 6 between the two weirs 2, the discharge port 28 of the lower nozzle 5b can be accurately set at a predetermined position in the molten steel reservoir 3.

In the above embodiment, both ends of the water surface protection cover 6 are mounted and supported between the two dams 2. However, a new mounting frame is provided, and the water surface protection cover 6 is mounted on the mounting frame. It may be set above the molten steel surface.

[0024]

As described above, at the start of casting, the lower nozzle is inserted in advance into the nozzle insertion hole of the metal surface protection cover and attached at the start of casting, so that the outer peripheral surface of the lower nozzle and the inner circumference of the nozzle insertion hole are formed. Since the gap with the surface is sealed by the seal material, it is difficult for air to flow between the molten steel surface protection cover and the molten steel surface through this clearance, and therefore, a small amount of inert gas is removed from the molten metal surface protection cover. By supplying between the molten steel surface and the surface, the inflow of air can be prevented. As described above, since the supply amount of the inert gas can be reduced, the cost can be reduced. Then, as described above,
The tundish after attaching the
Move the upper flange of the upper nozzle to the fitting groove of the lower nozzle.
Fits. At this time, the upper slope faces the lower slope
The upper flange is shifted laterally
Fitting into the fitting groove without
The nozzle and the lower nozzle are connected accurately without lateral displacement.
Are combined.

In addition, since the vicinity of the discharge hole is most severely damaged during casting, only the lower nozzle can be made of a material having excellent erosion resistance. I can do it. Further, if the vicinity of the discharge hole is damaged, only the lower nozzle needs to be replaced, and maintenance of the pouring nozzle becomes easy.

[Brief description of the drawings]

FIG. 1 is an enlarged vertical sectional view showing a fitting portion between an upper nozzle and a lower nozzle of a pouring nozzle according to an embodiment of the present invention.

FIG. 2 is a longitudinal sectional view showing the entire pouring nozzle.

FIG. 3 is a partially enlarged plan view showing a nozzle insertion hole of the hot water surface protection cover.

FIG. 4 is a longitudinal sectional view of a pouring nozzle in a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Mold roll (moving mold wall) 2 Weir body 3 Molten steel reservoir 4 Tundish 5 Pouring nozzle 5a Upper nozzle 5b Lower nozzle 6 Flush protection cover 28 Discharge port 34 Fused steel face 37 Nozzle insertion hole 40 Sealing material S2 Gap

Claims (1)

(57) [Scope of request for utility model registration] 1. A pouring nozzle for injecting molten steel from a tundish into a molten steel reservoir formed between a pair of moving mold walls arranged in parallel with each other and dams provided at both ends of the moving mold walls. And a surface protection cover for covering the molten steel surface.
Over the support fixed to a predetermined position between the two weirs body, it divides the pouring nozzle and the lower nozzle having a top nozzle discharge port, mounting the top nozzle on the tundish, which is formed on the melt surface protection cover nozzle the insertion hole, the mounting by inserting the bottom nozzle is provided with a sealing member for sealing a gap between the lower nozzle and the nozzle insertion hole, an upper to a lower end of the upper nozzle
Form a flange and attach it to the outer periphery of the lower surface of this upper flange.
The upper inclined surface of the direction is formed,
Form the lower flange and attach it to the lower flange.
The fitting groove forms a fitting groove that can fit freely, and the outer peripheral portion of this fitting groove
In addition, to form a lower inclined surface that can freely contact the upper inclined surface,
A movable mold wall, wherein a lower end of the upper nozzle is detachably connected to an upper end of a lower nozzle to which the above-mentioned water level protection cover is attached by fitting an upper flange into the fitting groove. Pouring nozzle in continuous casting equipment.