Submerged nozzle for continuous casting

Abstract

To provide a nozzle for continuous casting that prevents peeling of mortar and misalignment of the nozzle body or the metal case in a high-temperature environment. 【Solution means】For a nozzle for continuous casting, particularly a quick-change type immersion nozzle 10, a neck portion 10a, a joint portion 10c, and a sliding plate 12 are covered by a metal case 11. The metal case is fixed to the nozzle body by mortar filled in a gap 15 between the nozzle body and the metal case. Here, the immersion nozzle has a locking portion 20 provided with a recess 21 that depresses along the radial direction in a longitudinal cross-sectional view at a predetermined position on the peripheral wall surface of the neck portion. The mortar filled up to the depth of the recess 21 solidifies and is locked to the locking portion. As a result, the contact area of the mortar with respect to the neck portion is increased and the adhesion is improved, so that it is possible to prevent the nozzle body or the metal case from deviating from a predetermined position in a high-temperature environment such as preheating.

Description

Technical Field

[0001] The present invention relates to a nozzle for continuous casting. Immersion

Background Art

[0002] A nozzle for continuous casting is a refractory for pouring molten steel into another molten steel holding container such as a tundish or a mold below, which is joined to the molten steel outlet of a single molten steel holding container located above such as a ladle or a tundish. Therefore, the nozzle body of the nozzle for continuous casting may be covered with a metal case from the viewpoint of preventing damage during movement and replacement. The metal case is composed of a predetermined refractory powder and clay, and is fixed to the nozzle body using a mortar having plasticity as an adhesive.

[0003] The nozzle for continuous casting disclosed in Japanese Patent Application Laid-Open No. 2-217144 takes a long nozzle as an example. When fixing the metal case to the nozzle body, protrusions are provided on the nozzle body to equalize the thickness of the mortar and facilitate the positioning of the metal case, thereby improving the fitting accuracy of the metal case.

[0004] Among such nozzles for continuous casting, the immersion nozzle used in the injection process of joining to the molten steel outlet of the tundish and performing the process of injecting molten steel into the mold disposed below is frequently replaced at least once or several times for each such injection process. An immersion nozzle developed to smoothly and quickly perform this frequently performed nozzle replacement operation without cooling the molten steel and the next preheated nozzle is called a quick-change type. The quick-change type immersion nozzle has a flat sliding plate joined to the nozzle neck that fits into a sliding guide installed near the molten steel outlet of the tundish. ​The above-mentioned metal case covers at least such a sliding plate and the nozzle head, protecting them from the impact during replacement. Near the tundish, a nozzle changer and a preheating device are installed. The nozzle changer is configured to push out the sliding plate from the unused submerged nozzle side with respect to the submerged nozzles in use and the unused submerged nozzles arranged along the sliding guide. As a result, the submerged nozzle in use is pushed out, and it can be quickly replaced with an unused submerged nozzle. The preheating device is configured to heat the submerged nozzle together with the metal case covering the head of the nozzle body and the sliding plate, and preheat the new submerged nozzle to be used next to a predetermined temperature.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] In the above nozzle for continuous casting, high-temperature molten steel flows through the nozzle inner hole. Particularly among the nozzles for continuous casting, the submerged nozzle is preheated to a predetermined temperature before use so as not to be damaged by the heat shock caused by the high-temperature molten steel flowing through the nozzle inner hole, and is used in a high-temperature environment. When the nozzle body, mortar, and metal case are heated in such a high-temperature environment, the nozzle body, mortar, and metal case all thermally expand. In this case, the expansion rate of the mortar may be larger than that of the nozzle body or the metal case. Here, continuous casting nozzles each composed of a substantially cylindrical nozzle body and a metal case covering the nozzle body are all joined to the molten steel outlet of a single molten metal holding container disposed above, and are used in a state standing along the axial direction so as to pour molten steel into another molten metal holding container disposed below. During use, that is, while hot molten steel is flowing down or being preheated in the nozzle inner hole, after greatly thermal expanding, if the molten steel breaks off, or when the preheating is completed and it is in standby, the continuous casting nozzle is cooled by natural heat dissipation or the like, and the expanded mortar or the like cools and contracts. When the mortar that has greatly expanded compared to the nozzle body or the metal case contracts to a thickness less than the original, it may peel off from the nozzle body or the metal case, and a gap may be formed in the peeled portion. When such mortar peels off from the nozzle body or the metal case, since the continuous casting nozzle is used standing upright, there is a problem that the nozzle body or the metal case may drop or fall off from a predetermined position under its own weight together with the weight of the mortar.

[0007] The misalignment of the nozzle body or the metal case as described above is a problem that can occur in continuous casting nozzles equipped with a metal case and used in a high-temperature environment. In recent years, particularly in the case of quick-change type immersion nozzles that are preheated to a higher temperature, it can become an even more prominent problem. This is presumably because the quick-change type immersion nozzle has a flat sliding plate that protrudes greatly from the upper end surface of the neck of the nozzle body, and the weight of the metal case covering the sliding plate that is in an overhanging state from the neck of the nozzle body becomes a large load on the lower mortar. And if the metal case deviates or comes off and twists from the specified position during preheating, the immersion nozzle cannot be set in the nozzle changer, the timing and replacement cycle of replacing the immersion nozzle change, and there is a risk that continuous casting cannot be carried out as planned.

[0008] Here, in the invention related to the continuous casting nozzle disclosed in Japanese Patent Application Laid-Open No. 2-217144, in which a protrusion is provided on the nozzle body to improve the positioning accuracy of the metal case, since a long nozzle is exemplified in the detailed description of the invention, it is not clear whether a structure in which simple protrusions are provided at various positions of the nozzle body can prevent the mortar from peeling off and fix a metal case that protrudes greatly together with the sliding plate. However, the present inventor has conceived that by making appropriate improvements based on the prior invention related to the continuous casting nozzle, it may be possible to enhance the effect of preventing the displacement of the metal case covering the sliding plate.

[0009] Therefore, the problem to be solved by the present invention is to provide a continuous casting nozzle that prevents the mortar from peeling off in a high-temperature environment and prevents the displacement of the nozzle body or the metal case. Immersion An object of the present invention is to provide such a nozzle.

Means for Solving the Problem

[0010] The continuous casting nozzle according to claim 1 Immersion is A joint part provided with a substantially flat sliding plate, composed of a neck portion having a substantially inverted frustum shape and a body portion having a substantially cylindrical shape integrally connected to the lower end of the neck portion The lower surface part of the joint part is integrally connected to the upper end surface of the head part, as a nozzle body, and a metal case covering the neck portion of the nozzle body, The joint part and and is a continuous casting nozzle in which a predetermined refractory having plasticity is filled in a gap formed between the nozzle body and the metal case to fix the metal case to the nozzle body, characterized in that a locking portion formed by any one or both of recessing along the radial direction or protruding along the radial direction is provided at a predetermined position on the circumferential wall surface of the neck portion, and the refractory is locked to the locking portion when the circumferential wall surface is viewed in a longitudinal sectional view along the axial direction. Immersion When the circumferential wall surface of the neck portion is viewed in a longitudinal sectional view along the axial direction, a locking portion formed by any one or both of recessing along the radial direction or protruding along the radial direction is provided at a predetermined position on the circumferential wall surface of the neck portion, and the refractory is locked to the locking portion. Together with a concave groove formed along the circumferential direction of the peripheral wall surface, Or When the peripheral wall surface is viewed in a longitudinal sectional view along the axial direction, Protruding along the radial direction Together with a ridge formed along the circumferential direction of the peripheral wall surface, One or both of them are provided to form a locking portion, characterized in that the refractory is locked to the locking portion. ​

[0011] The nozzle for continuous casting according to claim 2 Immersion In the invention according to claim 1, when the nozzle body is viewed in a longitudinal sectional view along the axial direction, the concave Groove and the Ridge are formed so as to be adjacent to each other alternately.

[0012] The nozzle for continuous casting according to claim 3 Immersion In the invention according to claim 1, the refractory is mortar.

Advantages of the Invention

[0013] According to the present invention In the immersion nozzle for continuous casting related thereto as follows, The immersion nozzle for continuous casting is composed of a joint part provided with a substantially flat sliding plate, a head part having a substantially inverted truncated cone shape, and a substantially cylindrical body part integrally connected to the lower end of the head part. It is composed of a nozzle body in which the lower surface part of the joint part is integrally connected to the upper end surface of the head part, and a metal case covering the joint part and the head part of the nozzle body. A predetermined refractory material with plasticity is filled in the gap formed between the nozzle body and the metal case to fix the metal case to the nozzle body. At this time, At a predetermined position on the peripheral wall surface of the head part, when the peripheral wall surface is viewed in a longitudinal sectional view along the axial direction, a locking part formed by either one or both of a concave groove that sinks along the radial direction and is formed along the circumferential direction of the peripheral wall surface, or a ridge that protrudes along the radial direction and is formed along the circumferential direction of the peripheral wall surface is provided so that the refractory material is locked to the locking part. Thus, the contact area of the refractory with respect to the head portion can be increased, and the adhesion degree of the refractory with respect to the head portion can be improved. And Concave groove is filled with a refractory, or Ridge bites into the refractory to fix the refractory to the locking portion. Therefore, even in a high-temperature environment such as preheating, when the refractory peels off from the nozzle body or the refractory is somewhat damaged and the weight of the refractory is added to the metal case, the refractory locked to the locking portion can hold the nozzle body or the metal case in a predetermined position. In this way, the adhesion degree of the refractory with respect to the head portion of the nozzle body is improved, and the refractory locked to the locking portion holds the metal case. Therefore, it is possible to prevent the nozzle body or the metal case from deviating from a predetermined position in a high-temperature environment such as preheating. Furthermore, by configuring it as a concave groove or a ridge along the circumferential direction, it is possible to prevent the manufacturing process of the nozzle from becoming complicated and suppress the manufacturing cost. And preferably, when the nozzle body is viewed in a longitudinal sectional view along the axial direction, Concave groove and Ridge are formed adjacent to each other alternately. Thus, the contact area of the refractory with respect to the head portion of the nozzle body is increased to improve the adhesion degree, Concave groove and RidgeSince the refractory material locked to the locking part composed of holds the metal case, it is possible to prevent the metal case from shifting from a predetermined position in a high-temperature environment such as preheating. More preferably, the refractory material is mortar. Thereby, the workability when fixing the metal case to the nozzle body can be improved.

Brief Description of the Drawings

[0014]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Figure 15

Figure 16

Figure 17

MODE FOR CARRYING OUT THE INVENTION

[0015] The present invention can obtain a high effect with respect to various nozzles used for continuous casting, and in particular, has a great effect on an immersion nozzle called a so-called quick change type. As shown in FIGS. 1 and 2, the quick change type immersion nozzle 10 for continuous casting is composed of a nozzle body and a metal case 11. The nozzle body is composed of a neck part 10a having a substantially inverted truncated cone shape, a cylindrical body part 10b connected and formed to the lower end of the neck part 10a, and a joint part 10c provided with a substantially flat sliding plate 12 connected and formed to the upper end of the neck part 10a. The specific shapes of the neck part 10a, the body part 10b, and the sliding plate 12 are appropriately designed. As shown in the figure, the metal case 11 includes a box-shaped portion 11a that covers the joint portion 10c, and a cylindrical portion 11b that is connected to the box-shaped portion 11a and surrounds the head portion 10a. Wind around The outer wall or the lower end surface of the box-shaped portion 11a is configured to be slidable along a guide rail (not shown) that guides the nozzle body to a predetermined position facing the molten steel outlet of the tundish (not shown). Thereby, by sliding the outer wall and the lower end surface of the box-shaped portion 11a along the guide rail, it is possible to quickly replace from one immersion nozzle to another immersion nozzle, and the metal case 11 protects the nozzle body from the impact generated during such replacement. As shown in FIG. 2, the gap 15 formed between the head portion 10a and the metal case 11 is filled with a refractory. The refractory is preferably a mortar formed by mixing a predetermined powdery refractory and clay at a predetermined ratio and kneading with water or a predetermined organic resin. By solidifying the filled mortar, the metal case 11 can be fixed to the nozzle body through the mortar. Hereinafter, each embodiment of the present invention will be described by taking as an example a nozzle in which the metal case 11 is assembled to the immersion nozzle 10 shown in FIG. 1 with mortar.

Embodiment

[0016] Examples of the nozzle for continuous casting according to the present invention Immersion will be described with reference to the accompanying drawings. FIG. 1 is an explanatory view illustrating an immersion nozzle for continuous casting as described above. And FIG. 2 is a partially enlarged cross-sectional view in which a joint portion and a part of a head portion of the immersion nozzle for continuous casting are enlarged when viewed in a longitudinal cross-section along the axial direction of the nozzle body.

[0017] The nozzle for continuous casting shown in FIG. 1 Immersion nozzle 10 is composed of a nozzle body and a metal case 11 as described above. The nozzle body is composed of a head portion 10a having a substantially inverted truncated cone shape, a cylindrical body portion 10b connected to the lower end of the head portion 10a, and a joint portion 10c connected to the upper end of the head portion 10a. As shown in the figure, the metal case 11 includes a box body portion 11a that covers the joint portion 10c, and a cylindrical body portion 11b that is connected and formed to the box body portion 11a and surrounds the head portion 10a. Wind around The outer wall or the lower end surface of the box body portion 11a is configured to be slidable along a guide rail (not shown) that guides the nozzle body to a predetermined position facing the molten steel outlet of the tundish (not shown). Thereby, by sliding the outer wall and the lower end surface of the box body portion 11a along the guide rail, it is possible to quickly replace from one immersion nozzle to another immersion nozzle, and the metal case 11 protects the nozzle body from the impact generated during such replacement. As shown in FIG. 2, the gap 15 formed between the head portion 10a and the metal case 11 is filled with a refractory. The refractory is preferably a mortar formed by mixing a powdered predetermined refractory and clay at a predetermined ratio and kneading with water or a predetermined organic resin. By solidifying the filled mortar, the metal case 11 can be fixed to the head portion 10a and the joint portion 11c of the nozzle body through the mortar.

[0018] The joint portion 10c includes a substantially flat sliding plate 12, and a nozzle inner hole 13a penetrating toward the head portion 10a is formed at a substantially central portion of the sliding plate 12. The upper surface side of the sliding plate 12 is configured to be in contact with and slidable with respect to a predetermined refractory installed around the molten steel outlet provided in the tundish.

[0019] As shown in FIG. 1, the head portion 10a having a substantially inverted frustum shape is configured such that the diameter of the upper end side is slightly larger than the diameter of the lower end side, and is formed to project outward as it goes toward the upper joint portion 10c side. The nozzle inner hole 13b provided in the head portion 10a communicates with the nozzle inner hole 13a of the joint portion 10c and penetrates along the axis toward the body portion 10b. A locking portion 20 is provided at a predetermined position on the outer peripheral wall surface of the head portion 10a. The cylindrical body portion 10b has its upper end connected and formed with the neck portion 10a, and has a pair of discharge ports 14 near its lower end. The nozzle inner hole 13c provided in the body portion is axially communicated from the nozzle inner hole 13b of the neck portion toward the discharge port 14. When the above-described dipping nozzle 10 is installed at a predetermined position facing the molten steel outlet of the tundish, the nozzle inner holes 13a, 13b, and 13c communicate from the molten steel outlet toward the discharge port 14, and molten steel can be supplied into the mold (not shown).

[0020] Here, FIG. 2 is an enlarged partial cross-sectional view showing a portion related to the gap 15 between the neck portion 10a and the metal case 11 when viewed in a longitudinal cross-section along the axial direction of the nozzle body. The locking portion 20 provided on the neck portion 10a is composed of a recess 21 cut out to a predetermined depth along the radial direction of the neck portion 10a as shown in FIG. 2. Note that the longitudinally cross-sectional shape of the recess 21 is not limited to the rectangular cross-section shown in FIG. 2. That is, the longitudinally cross-sectional shape of the recess may be, for example, a semi-circular recess 21a shown in FIG. 3(a), a trapezoidal recess 21b shown in FIG. 3(b), or a triangular recess 21c shown in FIG. 3(c).

[0021] And the recess 21 having the above-described longitudinally cross-sectional shape as the locking portion 20 forms a concave groove 22 formed so as to circumferentially go around the outer peripheral wall surface in a strip shape as shown in FIG. 4. Note that the locking portion 20 according to the present embodiment is a concave groove 22 for ease of processing, but is not limited thereto. For example, as shown in FIG. 5, a plurality of elongated slits 23 arranged at a predetermined interval along the circumferential direction with respect to the outer peripheral wall surface of the neck portion 10a may be used as the locking portion 20. Also, as shown in FIG. 6, a bottomed hole portion 24 having an opening end formed in a predetermined shape with respect to the outer peripheral wall surface of the neck portion 10a may be provided. These can obtain the same effects as the above-described recessed portion 21. The predetermined shape related to the opening end of the bottomed hole portion 24 is, for example, a circular opening end 24a shown in FIG. 6(a), a triangular opening end 24b shown in FIG. 6(b), or a rhombus-shaped or rectangular opening end 24c shown in FIG. 6(c). Thus, by providing the locking portion 20 at a predetermined position on the outer peripheral wall surface of the neck portion 10a, the mortar can be filled to the depths of the concave groove 22, slit 23, or bottomed hole portion 24 of the locking portion 20 and solidified. Therefore, the contact area of the mortar with respect to the neck portion 10a can be increased and the adhesion to the outer peripheral wall surface of the mortar can be improved, so that the mortar can be very firmly adhered to the neck portion 10a.

[0022] A heating test was conducted by placing the immersion nozzle 10 having the above-described configuration in an environment similar to the actual use state and preheating treatment. FIG. 7 shows an explanatory diagram after heating of the immersion nozzle 10 provided with the locking portion 20 according to the present embodiment, and FIG. 8 shows an explanatory diagram after heating of a conventional immersion nozzle which is a comparison target.

[0023] As shown in FIGS. 7 and 8, the heating test is a test in which the immersion nozzle according to the present embodiment and the conventional immersion nozzle are heated in a high-temperature environment of 1100° C. for 2 hours. In the conventional immersion nozzle shown in FIG. 8, a gap is generated between the lower surface of the joint portion 10c and the upper surface of the mortar, and the metal case 11 is displaced and lowered from the predetermined position before heating. On the other hand, in the immersion nozzle according to the present embodiment shown in FIG. 7, no gap is generated between the lower surface of the joint portion 10c and the upper surface of the mortar. Considering the generation of the gap and the displacement and lowering of the metal case 11 in the case of the conventional immersion nozzle, it is considered that the mortar filled between the peripheral wall surface of the neck portion 10a and the inner wall surface of the metal case 11 greatly thermally expanded during heating. That is, when the mortar that expands greatly during heating presses open the gap 15 between the peripheral wall surface of the neck portion 10a and the inner wall surface of the metal case 11, and then contracts as it cools after the heating test, in the so-called overhang portion that protrudes greatly on the lower surface side of the joint portion 10c with respect to the outer peripheral wall surface, the weight of the mortar itself and the metal case 11 to which the mortar is adhered is applied during such contraction, causing the adhesion on the joint portion 10c side to peel off, and it is considered that the mortar has dropped together with the metal case 11. Also, in heating tests other than the test results shown in FIG. 8, it was confirmed that the greater the temperature rise during heating, the greater the amount of displacement of the metal case 11 with respect to the nozzle body. From the above, it is considered that the thermal expansion of the mortar has a great influence on the formation of the gap between the metal case 11 and the joint portion 10c and the displacement and downward movement of the metal case 11 with respect to the nozzle body. In contrast, in the immersion nozzle 10 according to the present embodiment, even when the mortar filled between the peripheral wall surface of the neck portion 10a and the inner wall surface of the metal case 11 expands greatly during heating, the filled mortar expands so as to press open the gap between the peripheral wall surface of the neck portion 10a and the inner wall surface of the metal case 11, and thus expands toward the concave portion 21 related to the filled locking portion 20. Also, since the contact area of the mortar with respect to the neck portion 10a is widened and the adhesion is improved, the mortar does not peel off from the peripheral wall surface of the neck portion 10a before and after the heating test. Therefore, even when the mortar contracts as it cools, it does not fall off from the concave portion 21, and it is considered that there is no displacement of the metal case 11 with respect to the neck portion 10a. Since the immersion nozzle 10 is heated in a standing state during preheating, when the thermally expanded mortar contracts due to cooling, considering that the mortar filled horizontally, such as on the lower surface side of the joint portion 10c, drops and peels off due to its own weight and pulls the mortar filled in the vertical direction, it is not limited to providing the locking portion 20 at the neck portion 10a of the nozzle body as in the immersion nozzle 10 according to the present embodiment, and the same locking portion 20 as described above may be provided on the side surface of the joint portion 10c facing the inner side surface of the box portion 11a of the metal case 11. Even in this case, displacement of the metal case 11 can be prevented.

[0024] Therefore, according to the continuous casting nozzle according to this embodiment, particularly the quick-change type immersion nozzle 10, even after preheating, as shown in FIG. 7, it is possible to prevent the metal case 11 from shifting and dropping due to the mortar peeled off by thermal expansion. As a result, the quick-change type immersion nozzle can be quickly set on the guide rail after preheating, and can be quickly exchanged from the previous immersion nozzle in use along the guide rail to the subsequent immersion nozzle to be used next. Also, even for continuous casting nozzles other than the immersion nozzle 10, for example, for a continuous casting nozzle in which the nozzle body is housed in a metal case and the metal case is fixed to the nozzle body with mortar, by providing the locking portion 20 in the same manner as above, when exposed to a high-temperature environment during preheating or continuous casting, it is possible to obtain an effect of preventing the mortar from peeling off and the metal case 11 from falling off.

Example

[0025] Next, another embodiment of the continuous casting immersion nozzle will be described with reference to the attached drawings. FIG. 9 is a partially enlarged cross-sectional view showing an enlarged portion related to the gap between the neck portion and the metal case when viewed in a longitudinal cross-section along the axial direction of the nozzle body. The basic configuration of the immersion nozzle 10A according to this embodiment is the same as that of the first embodiment, so the description is omitted. The immersion nozzle 10A according to this embodiment and the immersion nozzle 10 described in the first embodiment are different in the configuration related to the sliding plate 12A and the locking portion 30.

[0026] The sliding plate 12A is configured such that its central position is different from that of the sliding plate 12 described in the first embodiment. The center of the sliding plate 12 is eccentric from the center of the nozzle inner hole 13 and has different lengths protruding on the left and right in the figure, whereas the sliding plate 12A is configured such that, as shown in FIG. 9, the center of the nozzle inner hole 13 and the center of the sliding plate 12A substantially overlap at a single point, and the lengths protruding on the left and right in the figure are equal. That is, the quick-change type immersion nozzle 10A for continuous casting provided with the sliding plate 12A has a sliding plate 12A protruding in a circular or square shape, and since the center portion of the sliding plate 12A coincides with the center of the nozzle inner hole 13, when setting it on the guide rail, it can be quickly set without considering the orientation of the immersion nozzle 10A due to the difference in the protruding length.

[0027] As shown in FIG. 9, the locking portion 30 is composed of a convex portion 31 protruding to a predetermined height along the radial direction of the neck portion 10a. Note that the shape of the convex portion 31 in a longitudinal sectional view is not limited to the rectangular cross section shown in FIG. 9. That is, the shape of the convex portion in a longitudinal sectional view may be, for example, a semi-circular convex portion 31a shown in FIG. 10(a), a trapezoidal convex portion 31b shown in FIG. 10(b), or a triangular convex portion 31c shown in FIG. 10(c).

[0028] And the convex portion 31 having the above-described shape in a longitudinal sectional view as the locking portion 30 forms a protrusion 32 formed so as to circulate the outer peripheral wall surface in a strip shape, as shown in FIG. 11. Furthermore, the locking portion 30 according to the present embodiment is not limited to the protrusion 32. For example, as shown in FIG. 12, elongated tongue pieces 33 arranged at a predetermined interval along the circumferential direction with respect to the outer peripheral wall surface of the head portion 10a may be used as the locking portions 30. Alternatively, as shown in FIG. 13, a plurality of protrusion portions 34 having a predetermined shape protruding along the radial direction from the outer peripheral wall surface may be arranged in a row or randomly arranged along the circumferential direction, and the same effects as those of the above-described ridges 32 and tongue pieces 33 can be obtained. The protrusion portions 34 having a predetermined shape arranged in a row along the circumferential direction are, for example, a hemispherical protrusion portion 34a shown in FIG. 13(a), a prismatic protrusion portion 34b shown in FIG. 13(b), or a triangular pyramid-shaped protrusion portion 34c shown in FIG. 13(c). Thus, by providing the locking portion 30 at a predetermined position on the outer peripheral wall surface of the head portion 10a, it is possible to reach the depth of the mortar layer that solidifies the locking portion 30. Therefore, the contact area of the mortar with respect to the head portion 10a can be increased, and the adhesion degree of the mortar to the outer peripheral wall surface can be improved, so that the mortar can be firmly adhered to the head portion 10a.

Example

[0029] Next, another embodiment of the immersion nozzle for continuous casting will be described with reference to the accompanying drawings. FIG. 14 is an enlarged partial cross-sectional view showing a portion related to the gap between the head portion and the metal case when viewed in a longitudinal cross-section along the axial direction of the nozzle body. The basic configuration of the immersion nozzle 10B according to this embodiment is the same as that of the first embodiment and the second embodiment, so the description thereof will be omitted. The immersion nozzle according to this embodiment and the immersion nozzle described in the first embodiment or the second embodiment differ in the configuration related to the locking portion 40.

[0030] As shown in FIG. 14, the locking portion 40 is configured by arranging a rectangular concave portion 41 cut out to a predetermined depth along the radial direction of the head portion 10a and a rectangular convex portion 42 protruding to a predetermined height along the radial direction of the head portion in parallel along the axial direction of the head portion. Note that the shape of the locking portion 40 in a longitudinal sectional view is not limited to the cross section in which the rectangular concave portion 41 and the convex portion 42 shown in FIG. 14 are arranged side by side. That is, the shape of the locking portion 40 in a longitudinal sectional view may be, for example, a shape in which the convex portion 42a is sandwiched between the semicircular concave portions 41a, 41a shown in FIG. 15(a), or for example, a shape in which the trapezoidal convex portion 42b is sandwiched between the trapezoidal concave portions 41b, 41b shown in FIG. 15(b), and in addition to the shape in which the trapezoidal convex portion 42c is sandwiched between the triangular concave portions 41c, 41c shown in FIG. 15(c), further, a cross-sectional shape formed by arbitrarily combining the trapezoidal, triangular, and semicircular cross-sectional shapes may also be used.

[0031] And the shape of the convex portion 42 sandwiched between the concave portions 41, 41 having the above-described shape in a longitudinal sectional view as the locking portion 40 is formed such that the belt portion 44 sandwiched between the concave grooves 43, 43 arranged side by side along the axial direction circulates around the outer peripheral wall surface of the head portion 10a, as shown in FIG. 16. Furthermore, the locking portion 40 according to the present embodiment is not limited to the concave grooves 43, 43 and the belt portion 44 shown in FIG. 16. That is, when the nozzle body is viewed in cross section along the axial direction, as a shape in which the convex portion 42 is sandwiched between the concave portions 41, 41, for example, as shown in FIG. 17, a plurality of circumferentially elongated tongue pieces 45 formed to protrude along the radial direction with respect to the outer peripheral wall surface of the head portion 10a and circumferentially elongated slits 46 formed in parallel above or below the tongue pieces 45 may be arranged at predetermined intervals. In this way, by providing the concavo-convex locking portion 40 at a predetermined position on the outer peripheral wall surface of the head portion 10a, the contact area between the locking portion 40 and the mortar layer can be increased and the adhesion to the outer peripheral wall surface of the mortar can be improved, so that the mortar can be firmly adhered to the head portion 10a.

[0032] According to the immersion nozzles 10, 10A, and 10B for continuous casting described in the first to third embodiments, when fixing the metal case 11 to the nozzle body by filling the gap 15 formed between the nozzle body and the metal case 11 with mortar, locking portions 20, 30, and 40 are provided at the neck portion 10a of the nozzle body to increase the contact area of the mortar with respect to the neck portion 10a and improve the adhesion. Thereby, even after heating such as preheating, displacement of the metal case 11 with respect to the nozzle body can be prevented. Therefore, in the quick-change type immersion nozzles 10, 10A, and 10B as shown in the embodiments, after preheating, they can be smoothly set to the quick-changer related to the immersion nozzles 10, 10A, and 10B. Moreover, it is not limited to the immersion nozzles 10, 10A, and 10B shown in the embodiments, and it can be widely applied to various nozzles such as long nozzles for continuous casting in which the metal case 11 is fixed to the nozzle body using mortar as an adhesive. In this case, not only the locking portions 20, 30, and 40 are provided at the neck portion 10a, but also a portion having the same shape as the locking portions 20, 30, and 40 may be provided at a predetermined position of the body portion 10b, or locking portions may be provided at predetermined positions of the neck portion 10a and the body portion 10b, respectively. In any case, when using mortar as an adhesive to fix the metal case 11 to the nozzle body, by providing irregularities on the peripheral wall surface side of the nozzle body to widen the contact area of the mortar layer, even when the mortar thermally expands in a high-temperature environment, the adhesive force of the mortar can be maintained, and the metal case 11 can be held at a predetermined position of the nozzle body before and after heating.

Explanation of Reference Numerals

[0033] 10, 10A, 10B... Immersion nozzles for continuous casting, 10a... Neck portion, 10b... Body portion, 10c... Joint portion, 11... Metal case, 12, 12A... Sliding plates, 13a, 13b, 13c... Nozzle inner holes, 14... Discharge port, 15... Gap, 20, 30, 40... Locking portions, 21... Concave portion, 22... Concave groove, 23... Slit, 24... Bottomed hole portion, 31... Protrusion, 32... Ridge, 33... Tongue piece, 34... Protruding portion, 41... Concave portion, 42... Protrusion, 43... Concave groove, 44... Belt portion, 45... Tongue piece, 46... Slit.

Claims

A dipping nozzle for continuous casting, comprising a joint part having a substantially flat plate-shaped sliding plate, a neck part having a substantially inverted truncated cone shape, and a substantially cylindrical body part integrally connected to the lower end of the neck part, wherein a lower surface part of the joint part is integrally connected to an upper end surface of the neck part to form a nozzle body, and a metal case covering the joint part and the neck part of the nozzle body. A dipping nozzle for continuous casting, wherein a predetermined refractory material having plasticity is filled in a gap formed between the nozzle body and the metal case to fix the metal case to the nozzle body. At a predetermined position on a peripheral wall surface of the neck part, when the peripheral wall surface is viewed in a longitudinal cross section along the axial direction, a locking part is formed by either one or both of a concave groove that depresses along the radial direction and is formed along the circumferential direction of the peripheral wall surface, or a protrusion that protrudes along the radial direction and is formed along the circumferential direction of the peripheral wall surface when the peripheral wall surface is viewed in a longitudinal cross section along the axial direction. The dipping nozzle for continuous casting is characterized in that the refractory material is locked to the locking part. Claim 2 The dipping nozzle for continuous casting according to claim 1, wherein when the nozzle body is viewed in a longitudinal cross section along the axial direction, the concave grooves and the protrusions are formed adjacent to each other alternately. Claim 3 The dipping nozzle for continuous casting according to claim 1, wherein the refractory material is mortar.

Images