APPARATUS FOR CONTINUOUS SLAB CASTING

Abstract

The apparatus for continuous slab casting having a nozzle exchanging-holding mechanism capable of moving a submerged nozzle at the exchange of the nozzle through a moving-connecting space D of a base under a slide valve mechanism and keeping the connection between the submerged nozzle and the slide valve mechanism during the operation, and a rotation mechanism to rotate the base of the nozzle exchanging-holding mechanism, which is characterized by a fixing mechanism that fixes the submerged nozzle in the nozzle exchanging-holding mechanism by pressing the submerged nozzle toward one or both inner sides of the moving-connecting space D of the base in one or both directions perpendicular to the moving direction of the submerged nozzle during the nozzle exchange.

Claims

1. An apparatus for continuous slab casting including a slide valve mechanism, a submerged nozzle to guide molten metal from a tundish to a mold through the slide valve mechanism, a nozzle exchanging-holding mechanism to move the submerged nozzle through a moving-connecting space D provided to a base under the slide valve mechanism at the exchange of the submerged nozzle and to keep the connection between the submerged nozzle and the slide valve mechanism by pressing the submerged nozzle upward during the operation, and a rotation mechanism to rotate the base of the nozzle exchanging-holding mechanism, the apparatus comprising: a fixing mechanism to fix the submerged nozzle in the nozzle exchanging-holding mechanism by pressing the submerged nozzle to an inside of the moving-connecting space D of the base and to a direction perpendicular to the moving direction of the submerged nozzle at the exchange of the submerged nozzle, wherein the fixing mechanism comprises elastic materials or actuators provided to one of two pieces forming the moving-connecting space D, and fixes the submerged nozzle by biasing one side surface of a flange of the submerged nozzle in the moving-connecting space D and pressing an other side surface of the flange against the inside of an other piece by means of the elastic materials or actuators.

2. (canceled)

3. An apparatus for continuous slab casting, including a slide valve mechanism, a submerged nozzle to guide molten metal from a tundish to a mold through the slide valve mechanism, a nozzle exchanging-holding mechanism to move the submerged nozzle through a moving-connecting space D provided to a base under the slide valve mechanism at the exchange of the submerged nozzle and to keep the connection between the submerged nozzle and the slide valve mechanism by pressing the submerged nozzle upward during the operation, and a rotation mechanism to rotate the base of the nozzle exchanging-holding mechanism, the apparatus comprising: a fixing mechanism to fix the submerged nozzle in the nozzle exchanging-holding mechanism by pressing the submerged nozzle to an inside of the moving-connecting space D of the base and to a direction perpendicular to the moving direction of the submerged nozzle at the exchange of the submerged nozzle, wherein the fixing mechanism comprises elastic materials or actuators respectively provided to two pieces forming the moving-connecting space D, and fixes the submerged nozzle by biasing a flange of the submerged nozzle in the moving-connecting space D from both sides by means of the elastic materials or actuators.

4. The apparatus for continuous slab casting according to claim 3, wherein fixing members are attached to tips of the elastic materials or the actuators in a direction parallel to the moving direction of the submerged nozzle, and the fixing members press one side surface of the flange of the submerged nozzle.

5. The apparatus for continuous slab casting according to claim 4, wherein biasing force of the fixing mechanism is 300 to 5000N (30 to 500 kgf).

6. The apparatus for continuous slab casting according to claim 4, wherein projections projecting to a direction perpendicular to the moving direction of the submerged nozzle are provided on both ends on an abutting surface of the fixing member to the submerged nozzle in the moving direction, and the projections are provided with tapers on the upstream side and the downstream side of the moving direction of the submerged nozzle.

7. The apparatus for continuous slab casting according to claim 3, wherein fixing members are attached to tips of the elastic materials or the actuators in a direction parallel to the moving direction of the submerged nozzle, and the fixing members press both side surfaces of the flange of the submerged nozzle.

8. The apparatus for continuous slab casting according to claim 7, wherein biasing force of the fixing mechanism is 300 to 5000N.

9. The apparatus for continuous slab casting according to claim 7, wherein projections projecting to a direction perpendicular to the moving direction of the submerged nozzle are provided on both ends on an abutting surface of the fixing member to the submerged nozzle in the moving direction, and the projections are provided with tapers on the upstream side and the downstream side of the moving direction of the submerged nozzle.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0028] FIG. 1 is a front view of a slide valve device provided with a conventional submerged nozzle exchanging-holding mechanism and a conventional submerged nozzle rotation mechanism;

[0029] FIG. 2 is a plan view (bottom view) of the slide valve device shown in FIG. 1;

[0030] FIG. 3 is a front view showing an example of embodiments of the present invention;

[0031] FIG. 4 is a plan view (bottom view) looked up from the lower side of the present invention;

[0032] FIG. 5 is a cross sectional view of a portion of fixing a submerged nozzle of the present invention; and

[0033] FIG. 6 is an enlarged view of a fixing member and a slide guide.

DESCRIPTION OF EMBODIMENTS

[0034] FIG. 3 is a front view showing an example of embodiments of the present invention, FIG. 4 is a plan view (bottom view) looked up from the lower side of the present invention, and FIG. 5 is a sectional view of a part of fixing a submerged nozzle. The prior art shown in FIG. 1 is configured that the base 11 of the nozzle exchanging-holding mechanism is held in the seal case 9 by the support guide roller 22, but embodiments of the present invention is configured as follows.

[0035] Basically, a ring-shaped support guide 21a is fixed on an upper end of the base 11, and a support guide 21b is fixed on a lower surface of the seal case 9 in a state that a part of the support guide 21b is engaged with the support guide 21a, so that the base 11 is rotatable by sliding the guides 21a and 21b mutually.

[0036] Specifically, a width of moving-connecting space D corresponding to an upper part of the base 11 covering the lower nozzle 4 is larger than the width of the flange of the submerged nozzle 6, through which the center part of the seal case 9 can been seen from the lower side. Moreover, a ring-shaped support guide 21a is fixed on the upper surface of the base 11, and a ring-shaped support guide 21b is fixed on the lower surface of the base 11, so as to project the support guide 21 b from the lower surface of the seal case 9 to receive the support guide 21a, specifically, (in a state that the support guides 21a and 21b are engaged each other). Thereby, the base 11 is held rotatably by the support guide 21a and the support guide 21b. Like the conventional manner, the rotational force to the base 11 is given to the base 11 from the hydraulic cylinder 23 fixed on the seal case 9 through a lever 27.

[0037] Two pieces 11a and 11b are provided in the right and left directions of the base 11 that is a platform of the nozzle exchanging-holding mechanism. Two spring holes 33a are made on inside of the moving-connecting space D of the piece 11a, at two positions of upstream and downstream sides of the nozzle moving direction (an arrow direction in FIG. 5) toward the moving-connecting space D. Coil springs 33 are inserted in the spring holes 33a through volts (fixture legs 32) inserted in the spring holes 33a, and a fixing member 31 is provided on the two coil springs 33 over the nozzle moving direction. As shown in FIG. 5, the coil springs 33 are inserted to the volts 32, and attached with the fixing member 31 keeping a moving clearance so as to move in a specific width in the right and left directions. Accordingly, the fixing member 31 is biased in the right and left directions.

[0038] On the other hands, on the inside of the moving-connecting space D of the piece 11b of the base 11 on an opposite side to a side attached with the fixing member 31, a slide guide 14 is formed integrally with the piece 11b like the conventional manner. Thereby, when the submerged nozzle 6 is inserted in the moving-connecting space D, the fixing member 31 presses a side surface of the flange 15 of the submerged nozzle 6 against the right and left directions to push the slide guide 14 inside of the piece 11b to the opposite side. Thereby, the submerged nozzle 6 rotates by an angle corresponding to the motion of the driving device 23 when the submerged nozzle rotates.

[0039] At the exchange of the submerged nozzle, the submerged nozzle 6 is pushed to the moving direction. At this time, since the fixing member 31 is simply pressing the submerged nozzle 6 by appropriate force described hereinafter, the fixing member 31 can escape toward the direction inverse to the pressed direction, so that the submerged nozzle can be exchanged easily.

[0040] The number of the fixture legs 32 is two in FIG. 5, but it may be 1, or 3 or more. FIG. 5 shows an example using the coil springs 33, but the elastic material like plate springs, volute springs, or torsion springs may be employed instead of the coil springs 33. In addition, the fixing member 31 may be pressed by means of various kinds of actuators. As examples of the actuators, hydraulic cylinders, oil-hydraulic cylinders, pneumatic cylinders, solenoid valves can be used.

[0041] It is preferable that the biasing force to press the flange 15 of the submerged nozzle 6 by the fixing mechanism is 300N to 5000N (30 kgf to 500 kgf). In case of less than 300N, when the driving device for changing the discharge direction rotates the base 11, a sliding surface on the lower nozzle 4 receives the friction resistance, and cannot resist the stress working in the inverse direction to the driving direction, so that the fixing member 31 cannot fix the submerged nozzle, therefore it is not preferable. In case of 5000N and more, since the fixing member 31 does not escape even when the submerged nozzle is pushed to the nozzle moving direction at the exchange of the submerged nozzle, the nozzle exchange cannot be performed, therefore it is not preferable. More preferably, the biasing force is 1000N to 3000N.

[0042] FIG. 6 is an enlarged view of the fixing member 31 of the fixing mechanism for pressing.

[0043] It is preferable that projections 37 are provided to the upstream side and downstream side of the fixing member 31, and moreover, tapers 37a, 37b are provided to the upstream side and the downstream side of the projections 37. Accordingly, the tapers 37a, 37b make a space between the fixing member 31 and the slide guide 14 on an approaching (withdrawing) side of the submerged nozzle 6, so that the flange 15 of the submerged nozzle 6 approaching from the upstream side of the moving direction (withdrawn to the downstream side of the moving direction) smoothly approaches (be withdrawn from) between the fixing member 31 and the slide guide 14.

[0044] An abutting surface 37c on the inside looked from a center of the fixing member 31 is formed to a shape along a periphery of the flange 15 of the submerged nozzle 6, and at the exchange of the submerged nozzle, the periphery of the flange 15 of the submerged nozzle 6 is mounted on the abutting surface 37c and the submerged nozzle 6 is fixed tightly.

[0045] The projections 37 provided to both ends of the fixing member 31 have an effect for preventing the submerged nozzle 6 from sliding off toward the moving direction at the rotating. On this account, a distance between the projections is set to a value close to a length in the moving direction of the flange of the submerged nozzle. The shape of the abutting surface 37c between the projections is not limited in particular, but it is preferable to be formed along with an R-chamfered surface where a corner of the periphery of the flange 15 is subjected to the R-chamfering, or to be formed along with a C-chamfered surface in case of the C-chamfering.

[0046] A height of the projection 37 is desired to be 1 to 5 mm. In case of 5 mm or more, a relief of the fixing member 31 becomes too large, and the submerged nozzle cannot be exchanged smoothly, therefore it is not preferable.

[0047] When the unused submerged nozzle 6n is set to the guide rails 16 of the nozzle exchanging-holding mechanism, it is better to make some clearance between the upstream side of the nozzle moving direction of the slide guide 14 and the downstream side of the flange 15 of the submerged nozzle 6. Due to the clearance, the setting of the submerged nozzle 6 is facilitated and the submerged nozzle can be moved easily. On the other hand, when the submerged nozzle 6 is held at a position to be used during the operation, it is preferable that the center of the submerged nozzle is positioned at a specific place, whereby the flange 15 of the submerged nozzle 6 is pressed and fixed on the slide guide 14 on the opposite side by the fixing mechanism.

[0048] According to the above description, it is configured as shown in the enlarged view of FIG. 6 that the abutting surface 14c at the center of the slide guide 14 abutting the flange 15 becomes a shape projecting a little to the moving-connecting space D, and the tapers are provided to the upstream side and the downstream side of the slide guide, whereby the submerged nozzle can be moved smoothly.

[0049] In addition, a configuration as shown in FIG. 5 and FIG. 6 is preferable, namely, a moving guide hole 36 for the fixing member 31 is provided to the piece 11a of the base 11, and a moving guide 35 that is a projection mounted by the moving guide hole 36 is provided to the fixing member 31, whereby the fixing member 31 can be configured to be prevented from moving the downstream direction along with the moving of the submerged nozzle 6 at the exchange of the submerged nozzle 6.

[0050] In the above description, the fixing member 31 is configured to be provided to one piece of the base 11, that is, the piece 11a, but it may be provided to both pieces, the pieces 11a and 11b, on the sides facing the nozzle moving space D. In this case, it is configured that the spring holes 33 are provided to the other side of piece 11b, and the coil springs 33 are inserted in the spring holes 33a, and the fixing member 31 is fixed by the coil springs 33. It is nevertheless to say that the slide guides 14 are replaced with the fixing member 31.

INDUSTRIAL APPLICABILITY

[0051] As described above, in the apparatus for the continuous slab casting in accordance with the present invention, the submerged nozzle can be tightly fixed on the base that is the plat form of the rotation mechanism when the direction of the discharge hole of the submerged nozzle is changed during the casting (operation), so that the direction can be changed to an accurate angle, and it is possible to perform the stirring of the molten metal appropriately according to the conditions of the mold. Therefore, it is possible to improve the quality of the strands.

REFERENCE SIGNS LIST

[0052] 1 Tundish [0053] 2 Upper nozzle [0054] 3a Upper plate (plate brick) [0055] 3b Slide plate (plate brick) [0056] 3c Lower plate (plate brick) [0057] 4 Lower nozzle [0058] 5 Housing [0059] 6 Submerged nozzle [0060] 6e After-use submerged nozzle [0061] 6n Unused submerged nozzle [0062] 7 Hydraulic cylinder for sliding [0063] 8 Slide case [0064] 9 Seal case [0065] 10 Submerged nozzle exchanging mechanism [0066] 11 Base [0067] 12 Coil spring [0068] 13 Clamper [0069] 14 Slide guide [0070] 15 Flange of submerged nozzle [0071] 16 Guide rail [0072] 21a Support guide [0073] 21b Support guide [0074] 22 Support guide roller [0075] 23 Driving device (Hydraulic cylinder) [0076] 27 Lever [0077] 31 Fixing member [0078] 32 fixture legs [0079] 33 Coil spring [0080] 35 Moving guide [0081] 36 Moving guide hole [0082] 37 Projection