JP2011131238A - Long nozzle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a long nozzle used in continuous casting whose durability is improved without a complex structure and which reduces running costs in continuous casting. <P>SOLUTION: A long nozzle 1 includes: a nozzle body 2 having an annular fitting face 1a that is to be fitted to the bottom edge of a nozzle-shaped outflow part 3, from which molten metal is flown out; a nozzle head 2a, which is held on the upper side of the nozzle body 2, and which has a porous material 13, inserted from the bottom edge of the outflow part 3, for blowing a gas into a gap 1b between the outflow part 3 and the fitting face 1a of the nozzle body 2 and has a socket 12 for supplying the gas to the porous material 13; and a protection shell 4 covering the outer periphery of the nozzle body 2. At least the porous material 13 is separably incorporated in the nozzle body 2. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a structure of a nozzle head of a long nozzle through which molten metal (molten metal) such as molten steel flows.

  In the continuous casting etc. which handle molten metal (molten metal) such as molten steel, various devices for delivering the molten metal to a predetermined facility have been made. For example, when pouring molten steel in a ladle into a tundish, a long nozzle is used to prevent oxidation of the molten steel flowing down the nozzle and splash of splash. Furthermore, at the head of the long nozzle, an inert gas (nitrogen, argon gas, etc.) spraying structure is integrally formed in the protective skin covering the long nozzle, and the dynamic pressure of the molten metal flowing down the nozzle bore Oxidation (entrainment of ambient air) due to the negative pressure generated by is prevented.

  The structure (side sectional view) of a conventional long nozzle is shown in FIG. The long nozzle 1 has an annular fitting surface 1a and is fitted to a lower nozzle 3 disposed below the ladle. The nozzle head 2a of the long nozzle 1 is provided with an inert gas blowing structure for preventing the molten metal from being oxidized. The socket 5 for supplying the inert gas and the porous material 6 held in the protective skin 4 are the main parts of the structure, and are formed integrally with the protective skin covering the long nozzle 1, thereby improving airtightness. It is increasing. Then, an inert gas is caused to flow in from a socket 5 protruding in a radial direction from the protective skin 4 (indicated by a thick arrow direction in FIG. 5), so that the fitted lower nozzle 3 and an annular shape surrounding the nozzle 3 are provided. Entrainment of air generated from the gap 1b with the fitting surface 1a is prevented (a long nozzle having such a head structure is disclosed in, for example, Patent Documents 1-6).

Japanese Utility Model Publication No. 56-16555 JP 59-225862 A Japanese Utility Model Publication No. 01-023657 JP 62-279072 A Japanese Utility Model Publication No. 01-100516 Japanese Patent No. 2934187

  The protective skin covering the head of the long nozzle is a protective skin covering the nozzle body at the same time. The porous material (porous refractory material) is integrally held and fixed in the protective skin that covers the nozzle body and the nozzle head in common, ensuring airtightness as a long nozzle, and the surrounding air. Unnecessary interference is prevented (Patent Documents 1-3).

  And the inert gas which flowed in through the socket provided in the outer periphery of the protective skin is uniformly blown into the gap between the lower nozzle and the fitting surface through the porous material. The gas pressure around the lower nozzle is increased by the gas pressure filled in the gap between the lower nozzle and the fitting surface. Even if a negative pressure is generated in the nozzle hole due to the dynamic pressure of the molten metal flowing down the nozzle hole, the negative pressure is relieved by the gas pressure of the inert gas filled in the gap. Entrainment of air is prevented. Stable sealing performance as a long nozzle is ensured. (Patent Documents 4-5).

  As described above, in continuous casting or the like that handles molten metal, it is essential to maintain and secure the sealing performance against the entrainment of air caused by the negative pressure generated by the molten metal flowing down in each nozzle. Even during continuous casting operation, during maintenance work (replacement work) from a ladle with little remaining hot water to a ladle filled with molten metal (replacement work), predetermined maintenance work (for example, adhered to the fitting surface of the long nozzle head) The remaining steel removal work and the oxygen gas washing work to wash the fixed metal are performed to maintain and secure the function as a long nozzle.

  However, even if the maintenance work is performed, the function of the long nozzle gradually deteriorates with the replacement frequency of the ladle to be fitted, and the replacement life is reached. In particular, regarding an inert gas blowing structure provided at the head of the long nozzle, between the protective skin that integrally covers the nozzle and the porous material held and fixed in the protective skin (for example, FIGS. 5 and 4b). It is remarkable.

  That is, since the linear expansion coefficients of the porous material held and fixed in the protective skin, the refractory material of the nozzle body, and the protective skin are different, the heat history is repeated by heating and cooling repeated every time the ladle is replaced. As a result, looseness, looseness, and the like were generated between the protective skin contacting the porous material and the porous material (for example, FIGS. 5 and 4b). Further, the gas leaking irregularly from the gap between the porous material and the protective skin has lowered the gas pressure in the gap between the lower nozzle and the fitting surface, resulting in functional deterioration such as air entrainment. As described above, the long nozzle, which is unable to ensure stable sealing performance, has been replaced with a new long nozzle, ensuring the sealing performance necessary for continuous casting.

  In other words, in the conventional long nozzle structure, the deterioration of the sealing performance of the inert gas blowing structure determines the life of the long nozzle. For example, the nozzle body extending to the tundish is in a healthy state. However, in order to maintain and secure the function as a long nozzle, the entire long nozzle must be replaced, and there is a problem that the running cost of continuous casting is high.

  In Patent Document 6 (Japanese Patent No. 2934187), an inert gas blowing flow path capable of arbitrarily setting an inert gas blowing flow rate is provided at the upper and lower portions of the long nozzle, respectively, so that the sealing performance is deteriorated. The device has been devised to ensure the stability of the gas sealing performance by adjusting the gas flow rate to be supplied. However, for example, if the gas pressure is to be increased in a state where the sealing performance is deteriorated due to the difference in the linear expansion coefficient, the flow rate of the inert gas to be supplied must be increased.

  In other words, in order to maintain and secure the function of the long nozzle, it is necessary to increase the consumption of inert gas, and although the service life of the nozzle itself is slightly extended, the overall cost of continuous casting is reduced. Is not reached.

  The present invention has been made in view of the above-mentioned problems, and relates to a long nozzle used for continuous casting, which can improve durability without requiring a complicated structure and can reduce running costs in continuous casting. The purpose is to provide a long nozzle.

  The inventor of the present application is that the long nozzle life is mainly caused by the deterioration of the inert gas blowing structure provided in the nozzle head. A porous body provided on the nozzle head, paying attention to the fact that the protective skin is conspicuous between the protective skin and the porous material held in the protective skin, and that the nozzle body and the porous material have high durability. The present invention was arrived at in the light of separating the structure for injecting inert gas through the material (porous material, gas injection socket, etc.) from the nozzle body in a detachable manner.

The invention according to claim 1, which has been made to achieve the above object,
A nozzle body having an annular fitting surface to be fitted to the lower end of the nozzle-like outflow portion from which the molten metal flows,
A porous material that is held on the upper side of the nozzle body, is inserted from the lower end of the outflow portion, and blows gas into a gap between the outflow portion and the fitting surface of the nozzle body, and the gas is supplied to the porous material A long nozzle comprising a nozzle head having a socket and a protective skin covering an outer periphery of the nozzle body, wherein at least the porous material is incorporated in a separable manner from the nozzle body. And

The invention according to claim 2 is the long nozzle according to claim 1,
A fixing tool for detachably fixing the nozzle head and the nozzle body;

The invention according to claim 3 is the long nozzle according to claim 2,
The fixing tool is a belt-like fastener that integrally tightens the outer peripheral surface of the nozzle head and the outer peripheral surface of the protective skin covering the nozzle body.

The invention according to claim 4 is the long nozzle according to claim 3,
The belt-shaped fastener has an inner peripheral surface that comes into contact with an outer peripheral surface of the nozzle head and an outer peripheral surface of the protective skin covering the nozzle body.

The invention according to claim 5 is the long nozzle according to any one of claims 3-4,
The fixture has a notch for avoiding interference with the socket.

The invention according to claim 6 is the long nozzle according to claim 2,
The fixing tool projects in a radial direction from an outer peripheral surface of the nozzle head, and forms a pair with a plurality of claw members having a U-shaped cross section extending in the nozzle body direction, and covers the nozzle body. It comprises a plurality of locking members protruding radially on the outer peripheral surface of the protective skin, and the head and the nozzle body are integrally fixed by fitting the claw member and the locking member.

The invention according to claim 7 is the long nozzle according to claim 6,
The fitting surface between the claw member and the locking member is provided with a tapered inclination in the circumferential direction of the nozzle body, and when the claw member and the locking member are fitted together, The nozzle head and the nozzle body are fastened and fixed.

Invention of Claim 8 is the long nozzle as described in any one of Claims 6-7,
The pairs of the claw member and the locking member are arranged at an equal angle based on the number of installations, and are arranged at a plurality of locations.

The invention according to claim 9 is the long nozzle according to any one of claims 1-8,
The nozzle head is a porous ring integrally formed by gripping at least the porous material in a ring shape with a gripping material having a substantially U-shaped cross section and projecting the socket in a radial direction from the outer peripheral surface of the gripping material. is there.

The invention according to claim 10 is the long nozzle according to claim 9,
The lower end surface of the porous ring and the upper end surface of the nozzle body are in close contact with each other.

  According to an eleventh aspect of the present invention, in the long nozzle according to any one of the ninth to tenth aspects, the porous material is exposed on an inner peripheral surface of the porous ring.

The invention according to claim 12 is the long nozzle according to claim 11,
The gripping material has an upper flat portion and a lower flat portion that constitute parallel flat surfaces facing each other up and down across the porous material, and the radial length of the upper flat portion is the lower flat portion A part of the surface of the porous material exposed to the inner peripheral surface of the porous ring is exposed continuously to the upper flat portion and the lower flat portion.

  According to the configuration of the first aspect, at least the highly durable nozzle body and the porous material can be separated from each other, so that the deteriorated portion can be handled as an exchange unit. Since the durability of the long nozzle can be improved by separating and replacing the deteriorated portion, the running cost can be reduced. Highly durable nozzle body and porous material can be recycled.

  According to the configuration of the second aspect, the separable nozzle head and the nozzle body are detachably fixed integrally by using a fixing tool. According to the structure of Claim 3, since the outer peripheral surface of the contact part of a nozzle head and a nozzle main body can be covered simultaneously and fastened, fixing property can be ensured. According to the structure of Claim 4, since it has the inner peripheral surface contact | abutted to the outer peripheral surface of the junction part of a nozzle head and a nozzle main body, the airtightness at the time of joining can be improved. According to the structure of Claim 5, a belt-shaped fastener functions as positioning in the gas supply direction at the time of ladle replacement | exchange at the same time it avoids interference with a fixing tool and a socket.

  According to the structure of Claim 6, fixation by the locking member provided in the outer peripheral surface of the nozzle head and the nozzle main body is attained. According to the configuration of the seventh aspect, for example, after the nozzle head provided with the claw member is fitted to the locking member provided in the nozzle body, the nozzle head is rotated in the circumferential direction. The abutment surface between the nozzle body and the nozzle body can be fastened. Airtightness at the time of close contact / contact can be improved. Moreover, the fastening force at the time of fastening can be adjusted. According to the structure of Claim 8, since the pair of locking members can be arrange | positioned by equiangular separation based on the number of installation of a pair of locking members, a fastening pressure can be disperse | distributed equally.

  According to the structure of Claim 9, since a socket and porous material can be integrated as a ring-shaped porous ring, it becomes possible to provide a gas spray structure as an exchange unit. According to the structure of Claim 10, it becomes possible to improve the airtightness at the time of contact | abutting and fixation. According to the structure of Claim 11, since the blowing of an inert gas can be provided uniformly with respect to a cyclic | annular fitting surface, it can be used effectively, without increasing the flow volume of the gas flowed in from the socket. According to the structure of Claim 12, since the gas can be blown into the periphery of the contact portion between the nozzle main body and the nozzle head, the sealing performance of the corresponding contact portion can be improved.

It is side surface sectional drawing which shows the embodiment which concerns on the long nozzle of this invention. It is a front view which shows the embodiment which concerns on the long nozzle of this invention. It is a side view including the partial cross section which shows the other embodiment which concerns on the long nozzle of this invention. It is a figure which shows embodiment of a porous ring, (a) is a top view, (b) is AA sectional drawing in (a) figure. It is side surface sectional drawing which shows the structure of the conventional long nozzle.

  Embodiments of the present invention will be described below in detail with reference to the drawings. In all the drawings in the present specification, the same reference numerals are given to portions corresponding to each other, and overlapping portions are appropriately omitted in the description to be described later.

Embodiment

  FIG. 1-2 shows an embodiment according to the long nozzle of the present invention, and shows a long nozzle 1 including a porous ring 10 that is detachably fixed to an upper portion of a nozzle body 2.

  The lower nozzle 3 that functions as a nozzle-like outflow portion from which the molten metal flows out is composed of a dense material, and is disposed below the ladle in this embodiment. The nozzle body 2 has an annular fitting surface 1 a that is fitted to the lower end 3 c of the lower nozzle 3. The porous ring 10 is held on the upper side of the nozzle body 2, and the porous material 13 for blowing an inert gas into the gap 1 b between the lower nozzle 3 and the fitting surface 1 a of the nozzle body 2 and the porous material 13 And a socket 12 for supplying gas. The porous ring 10 functions as a nozzle head 2 a having an inert gas blowing structure, and the porous ring 10 and the nozzle main body 2 are incorporated in a separable manner by a fixture 14.

  As is clear from FIG. 1, the gas spray structure including the porous material 13 is separated from the nozzle body 2 as a porous ring 10. That is, since the porous material 13 is not included in the protective skin 4 that covers the nozzle body 2, the sealing due to the difference in linear expansion coefficient that has conventionally occurred between the porous material and the protective skin (for example, FIGS. 5 and 4 b). There is no degradation of sex. The inert gas blowing structure (including at least a porous material) that is a deterioration factor of the long nozzle 1 can be handled as an exchange unit that can be incorporated into the nozzle body 2.

  The porous ring 10 that is the nozzle head 2 a and the nozzle body 2 are integrally fastened and fixed by a fixture 14 and function as the long nozzle 1. The long nozzle 1 is fitted to the lower nozzle 3, and conducts molten metal (molten metal) in the ladle to a tundish (not shown) while preventing secondary oxidation by the atmosphere. An inert gas (nitrogen, argon, etc.) is supplied from the socket 12 of the porous ring 10 at a predetermined gas flow rate. The inflowing inert gas is uniformly and uniformly blown into the ring-shaped gap 1b between the lower nozzle 3 and the annular fitting surface 1a through the porous material 13 held and fixed to the porous ring 10 ( In FIG. 1, it is indicated by a thick arrow direction).

  The atmospheric pressure around the fitting surface 1 a becomes higher than the atmospheric pressure around the long nozzle 1 due to the gas pressure of the inert gas that is blown and filled, and the inner hole 3 c of the lower nozzle 3 to the inner hole 2 c of the nozzle body 2. Since the negative pressure caused by the molten metal (melt) flowing down can be reduced, the entrainment of ambient air is suppressed and the oxidation of the melt can be prevented.

  As described above, since the nozzle body 2 and the porous material 13 having at least high durability can be separated from each other, the deteriorated portion can be handled as an exchange unit, and the nozzle body 2 can be recycled. Since the inside of the nozzle body 2 covered with the protective skin 4 does not include a porous material that contacts the protective skin 4, the durability of the nozzle body 2 is improved. The long nozzle 1 in which the deteriorated part can be separated and replaced can reduce the running cost.

  The lower nozzle 3 is disposed so as to protrude downward from a ladle (not shown), and conducts molten metal, which is a molten metal in the ladle, to the long nozzle 1. When the lower nozzle 3 and the long nozzle 1 are fitted, the lower end 3 c is fitted to the annular fitting surface 1 a of the nozzle body 2. The outer wall surface 3 b of the lower nozzle 3 faces the porous material 13 held and fixed to the porous ring 10. The molten metal in the ladle flows down through the inner hole 3a of the lower nozzle 3 and is conducted to the inner hole 2c of the nozzle body 2 without being exposed to air.

  As shown in FIG. 4, the porous ring 10 includes a porous material (porous refractory material) 13 and a gas supply socket 12. The porous material 13 is integrally formed in a ring shape by the grip material 11.

  The holding member 11 is a member having a substantially U-shaped cross section, and includes an annular upper flat portion 11a and a lower flat portion 11b having a width in the radial direction, and an annular outer annular surface 10b having a width in the vertical direction. The lower flat portion 11 b of the gripping material 11 is the lower end surface of the porous ring 10, and the outer annular surface 10 b also serves as the outer peripheral surface of the porous ring 10.

  The surface of the porous material 13 faces the outer wall surface 3b of the lower nozzle 3 when the lower nozzle 3 and the long nozzle 1 are fitted. A socket 12 for supplying an inert gas protrudes radially at one end of the outer peripheral surface 10 b of the porous ring 10.

  In the present embodiment, the outer peripheral surface (outer annular surface) 10b of the porous ring 10 and the upper outer peripheral surface 4a of the protective skin 4 that covers the nozzle body 2 are formed so that the surface positions are roughly the same. The lower end surface (lower flat portion) 11 b of the porous ring 10 is in close contact with and in contact with the upper end surface 2 b of the nozzle body 2. The configuration of the porous ring 10 will be described in detail later.

  In the present embodiment, the porous ring 10 can be provided as an exchange unit that can be separated from the nozzle body 2. For example, even if looseness or looseness due to the difference in linear expansion coefficient occurs between the porous material 13 and the upper flat portion 11a of the gripping material 11, it can be detached from the nozzle body 2 during maintenance work when replacing the ladle. By replacing with a porous ring, a stable sealing property can be provided. And since there is no need to increase the gas flow rate with the deterioration of the sealing performance, the running cost can be suppressed.

  The fixture 14 is a belt-like fastener having a band shape having a width in the vertical direction. The fixing tool 14 covers the outer peripheral surface (10b, 4a) of the contact portion between the porous ring 10 and the nozzle main body 2, and integrally fixes the two that are contacted in the vertical direction. The fixing tool 14 after covering the outer periphery may be fixed, for example, by bolting belt-shaped ends or by welding. If the nozzle body 2 and the porous ring 10 are separable, it will not be limited to this.

  The outer peripheral surface (10b, 4a) of the contact portion between the porous ring 10 that is the nozzle head 2a and the nozzle body 2 is simultaneously and integrally covered with the fixing device 14 that is such a belt-like fastener, and Since it can be fastened, it can be secured sufficiently as a long nozzle during operation.

  In order to ensure the airtightness of the contact portion between the porous ring 10 and the nozzle main body 2, the outer peripheral surface (outer annular surface) 10 b of the porous ring 10 and the upper outer peripheral surface 4 a of the protective skin 4 covering the nozzle main body 2 are It is desirable that the surface position is roughly the same surface. Furthermore, the inner peripheral surface of the fixture 14 that covers both the outer peripheral surfaces (10b, 4a) of the contact portion is the protective skin 4 that covers the outer peripheral surface (outer annular surface) 10b of the porous ring 10 and the nozzle body 2. It is desirable to be able to come into contact with the upper outer peripheral surface 4a.

  A sealing material such as packing is provided between the inner peripheral surface of the fixture 14 that is a belt-like fastener, the outer peripheral surface (outer annular surface) 10 b of the porous ring 10, and the upper outer peripheral surface 4 a of the nozzle body 2. It may be pasted and inserted to increase the airtightness of the contact part. In this case, the airtightness can be improved by adjusting the thickness of the sealing material in accordance with the position of each surface (10b, 4a) without previously setting the surface positions (10b, 4a) of both the surfaces to be roughly the same.

  Further, as shown in the front view of FIG. 2, the belt-shaped fixture 14 is provided with a semicircular cutout 14 a in the direction of the nozzle body 2. This is to avoid interference with the socket 12 of the porous ring 10 when the porous ring 10 and the nozzle body 2 are in contact with each other. At the same time, the arrangement position of the notch 14 a in the belt-shaped fixture 14 also serves as a positioning function for determining the position of the socket 12 when the inert gas is supplied to the long nozzle 1.

  The nozzle body 2 is mainly composed of a dense refractory material, and has an annular fitting surface 1a fitted to the lower end 3c of the lower nozzle 3 on the upper side thereof, and a protective skin 4 that is a cylindrical outer cylinder wall around the periphery. Covered with The molten metal flowing down from the fitted lower nozzle 3 further flows down the inner hole 2c of the nozzle body 2 and is conducted to a tundish (not shown). In addition, the porous material is not included in the protective skin 4 that covers the nozzle body 2, and the protective skin 4 does not have a portion that contacts the porous material.

  In this embodiment, it has the protective skin (upper end surface 2b) which continues to the protective skin 4 and extends the upper end of the nozzle body 2 in the radial direction. The upper end surface 2b and the lower end surface 11b of the porous ring 10 held and fixed on the upper side of the nozzle body 2 are in close contact with each other. Furthermore, the surface position of the outer peripheral surface (outer annular surface) 10b of the porous ring 10 and the upper outer peripheral surface 4a of the protective skin 4 covering the nozzle body 2 is formed to be roughly the same surface.

  In this embodiment, the conventional long nozzle has a problem by integrally forming an inert gas blowing structure (porous material 13, gripping material 11, socket 12) provided at the head of the conventional long nozzle. The main deterioration site can be provided as an exchange unit (porous ring 10) that can be separated from the nozzle body 2. Therefore, if a porous ring 10 that has received a heat history due to repeated heating and cooling each time the ladle is replaced and has deteriorated sealing performance is replaced with a new porous ring 10 and then mounted and fixed to the nozzle body 2, the running as a long nozzle Costs can be reduced. Since the porous material is not included in the protective skin 4 covering the nozzle body 2, the durability of the nozzle body 2 is not impaired.

  Since the porous material 13 is also highly durable like the nozzle body 2, it can be recycled. For example, the porous material 13 can be recycled by removing the porous material 13 after cutting the gripping material 11 of the porous ring 10 that has been deteriorated and separated and replaced, and holding and fixing the porous material 13 in a ring shape with the new gripping material 11. Can be realized.

  The porous ring 10 is held and fixed on the upper side of the nozzle body 2. At this time, the lower end surface 11b of the porous ring 10 and the upper end surface 2b of the nozzle body 2 are brought into close contact with each other, whereby the airtightness of the contact portion is enhanced. The inert gas supplied through the socket 12 of the porous ring 10 is filled in the gap 1b between the lower nozzle 3 and the fitting surface 1a via the porous material 13. Since the gas pressure around the contact portion can be maintained higher than the atmospheric pressure around the nozzle body by the filled gas pressure, the contact surface between the lower end surface 11 b of the porous ring 10 and the upper end surface 2 b of the nozzle body 2. No air entrainment occurs. Airtightness at the time of contact and fixation between the ring 10 and the nozzle body 2 can be secured.

  Further, as described above, the belt-shaped fixture 14 has an inner peripheral surface that abuts the upper outer peripheral surface 4 a of the protective skin 4 that covers the nozzle body 2 and the outer peripheral surface (outer annular surface) 10 b of the porous ring 10. Therefore, the airtightness is further enhanced. Airtightness can be secured with a simple structure without using a complicated structure when holding and fixing the porous ring 10.

  FIG. 4 shows an embodiment of the porous ring 10, FIG. 4 (a) shows a top view of the porous ring 10, and FIG. 4 (b) shows an AA side sectional view. Yes.

  In the porous ring 10, a porous material (porous refractory material) 13 and a gripping material 11 are integrally formed in a ring shape. The holding member 11 is a member having a substantially U-shaped cross section, and includes an annular upper flat portion 11a and a lower flat portion 11b having a width in the radial direction, and an annular outer annular surface 10b having a width in the vertical direction. On the inner peripheral surface of the porous ring 10, the surface of the held porous material 13 (inner annular surface 10a) is exposed.

  The outer annular surface 10 b of the gripping material 11 also serves as the outer peripheral surface of the porous ring 10. And the cylindrical socket 12 for supplying inert gas, such as nitrogen gas and argon gas, protrudes in the radial direction at the end of the outer side annular surface 10b.

  The porous material 13 that is a porous refractory material includes one or more of silicon dioxide (SiO 2), aluminum oxide (Al 2 O 3), zirconium oxide (ZrO 2), and chromium oxide (Cr 2 O 3). Excellent corrosion resistance and high oxygen resistance.

  The compounding ratio of the compounding material is, for example, 4 to 6 percent for silicon dioxide, 85 to 87 percent for aluminum oxide, 3 to 5 percent for zirconium oxide, and 3 to 4 percent for chromium oxide. And kneaded to produce. However, the composition is not limited to this.

  When the lower nozzle 3 and the long nozzle 1 are fitted, the exposed porous material 13 faces the outer wall surface 3 b of the lower nozzle 3. The inert gas supplied through the socket 12 is uniformly blown out evenly through the exposed porous material 13, and is filled in the ring-shaped gap 1b between the outer wall surface 3a of the lower nozzle 3 and the exposed porous material 13.

  The upper flat portion 11a and the lower flat portion 11b of the gripping material 11 having a substantially U-shaped cross-sectional shape form a flat surface parallel to each other in the radial direction. The length in the radial direction of the upper flat portion 11a (indicated by X in FIG. 4B) is longer than the length in the radial direction of the lower flat portion 11b (indicated by Y in FIG. 4B). Is formed. The lower flat portion 11b is in close contact with the upper end surface 2b of the nozzle body 2 as a lower end surface of the porous ring 10.

  In the AA side cross-sectional view shown in FIG. 4B, the porous material 13 has a rectangular cross-sectional shape. The length of the porous material 13 in the radial direction is longer than the radial length of the upper flat portion 11a and the lower flat portion 11b of the gripping material 11 (indicated by Z in FIG. 4B).

  Accordingly, a part of the surface of the porous material 13 held by the upper flat part 11a and the lower flat part 11b is not completely covered by the flat parts (11a, 11b), and the lower end face side of the porous ring 10 And it will be exposed to the upper end surface side (upper flat part 11a side).

  The porous material 13 exposed to the lower end surface 11b side of the porous ring 10 provides uniform gas blowing around the contact portion (11b, 2b) between the porous ring 10 and the nozzle body 2. Since the gas pressure around the contact parts (11b, 2b) can be maintained higher than the atmospheric pressure around the nozzle body by the uniformly filled gas pressure, the lower end surface 11b of the porous ring 10 and the upper part of the nozzle body 2 There is no air entrainment from the contact surface with the end surface 2b. As a result, the sealing performance by the inert gas can be enhanced.

  Note that the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention. Regarding the form of attaching / detaching / fixing the porous ring 10 and the nozzle body 2, for example, an embodiment without using the belt-like fixing tool 14 is possible.

  FIG. 3 shows another embodiment of the long nozzle that does not use the belt-like fixture 14. In FIG. 3, a wedge frame is provided on the porous ring 10 side (for example, the outer peripheral surface 10 b of the gripping material 11) and the protective skin 4 side (for example, the upper outer peripheral surface 4 a) that covers the nozzle body 2. . In this way, a pair of locking members (15a, 15b) having a wedge-frame relationship can be provided at a plurality of locations, and the porous ring 10 and the nozzle body 2 can be held and fixed so as to be separable.

  The locking member provided on the porous ring 10 side (the outer peripheral surface 10b of the gripping material 11) is a claw member 15b having a U-shaped cross section. The claw member 15b functions as a top, protrudes in the radial direction from the outer peripheral surface 10b of the porous ring 10, and extends in the direction of the nozzle body 2 located on the lower side.

  The locking member 15a provided on the protective skin 4 (upper outer peripheral surface 4a) covering the nozzle body 2 protrudes in the radial direction. The locking member 15a functions as a wedge that can be fitted to the frame. The claw member 15b and the locking member 15a form a matable pair.

  The fitting of the claw member 15b and the locking member 15a is performed by, for example, once bringing the porous ring 10 into close contact so that the claw member 15b is positioned in the outer peripheral area of the nozzle body 2 where the locking member 15a is not provided. Make contact. Next, the porous ring 10 is rotated in the circumferential direction (direction toward the locking member 15a) while sliding the corresponding contact surface so that the locking member 15a as a wedge is inserted inside the claw member 15b as a frame. Fit together.

  By providing such a locking structure, the porous ring 10 and the nozzle body 2 can be attached / detached / fixed with a simpler configuration and without the need for the belt-like fixture 14. In this case, it is not necessary to previously form the surface position of the outer peripheral surface 10b of the porous ring 10 and the upper outer peripheral surface 4a of the protective skin 4 of the nozzle body 2 so as to be roughly the same surface.

  In the present embodiment, the installation positions of the locking members (15a, 15b) functioning as wedge wedges are separated at an equal angle (for example, 120 degrees) according to the number of installation (for example, three positions), and are provided at a plurality of positions. Yes. As described above, the angular distribution is equally distributed according to the number of the locking members (15a, 15b) to be paired, and each pair is separated and provided at a plurality of locations, so that the porous ring 10 can be held and fixed. The pressing force (fixed pressure) on the contact surface can be evenly distributed. As long as separation is performed at an equal angle, it is possible to further increase the installation position of the pair of locking members (15a, 15b), increase the pressing force of the contact surface, and improve airtightness (for example, 90 degrees). 4 places installed at a distance from each other).

  In the present embodiment shown in FIG. 3, the fitting surface between the claw member 15 b provided on the outer peripheral surface 10 b of the porous ring 10 and the locking member 15 a provided on the upper outer peripheral surface 4 a of the nozzle body 2 is provided on the fitting surface. A tapered slope is provided along the circumferential direction. The lower end surface 11b of the porous ring 10 and the upper end surface 2a of the nozzle body 2 are brought into contact with each other and rotated in the circumferential direction (the locking member 15a side direction), thereby fitting the claw member 15b and the locking member 15a together. At the same time, it is configured to be fastened and fixed.

  By providing such a locking structure, the contact surface between the lower end surface 11b of the porous ring 10 and the upper end surface 2b of the nozzle body 2 can be tightly fastened at the same time as fitting, so that the airtightness can be further improved. . It is also possible to adjust the fastening pressure at the time of fastening.

  As another variation, the cross-sectional shape of the porous material 13 shown in FIG. 4 is a rectangular shape, but the porous material exposed in a row from the lower flat portion 11b is protruded in a convex shape toward the lower end surface side, and the nozzle body 2 It may be configured to increase the bonding area. With such a configuration, the surface of the exposed porous material is directly adhered to the upper end surface 2b side of the nozzle body 2, so that the sealing performance by the inert gas can be further improved.

1, long nozzle 1a, fitting surface 1b, gap 2, nozzle body 2a, head 2b, upper end surface 2c, inner hole 3, lower nozzle 3a, inner hole 3b, outer wall surface 4, protective skin 4a, upper outer peripheral surface 5 , Socket 6, porous material 10, porous ring 11, gripping material 11 b, lower end surface 12, socket 13, porous material
14, belt-shaped fixture 14a, semicircular cutout 15a, locking member 15b, claw member

Claims (12)

A nozzle body having an annular fitting surface to be fitted to the lower end of the nozzle-like outflow portion from which the molten metal flows,
A porous material that is held on the upper side of the nozzle body, is inserted from the lower end of the outflow portion, and blows gas into a gap between the outflow portion and the fitting surface of the nozzle body, and the gas is supplied to the porous material A long nozzle comprising a nozzle head having a socket and a protective skin covering the outer periphery of the nozzle body,
At least the porous material is incorporated so as to be separable from the nozzle body.
This is a long nozzle.   The long nozzle according to claim 1, further comprising a fixture that detachably fixes the nozzle head and the nozzle body.   The long nozzle according to claim 2, wherein the fixing tool is a belt-shaped fastener that integrally tightens an outer peripheral surface of the nozzle head and an outer peripheral surface of the protective skin covering the nozzle body.   The long nozzle according to claim 3, wherein the belt-shaped fastener has an inner peripheral surface that comes into contact with an outer peripheral surface of the nozzle head and an outer peripheral surface of the protective skin covering the nozzle body.   The long nozzle according to any one of claims 3 to 4, wherein the fixture has a notch for avoiding interference with the socket. The fixing tool protrudes in a radial direction from the outer peripheral surface of the nozzle head, and has a plurality of claw members having a U-shaped cross section extending in the nozzle body direction;
A pair with the claw member, comprising a plurality of locking members projecting radially on the outer peripheral surface of the protective skin covering the nozzle body,
The long nozzle according to claim 2, wherein the head and the nozzle body are integrally fixed by fitting the claw member and the locking member. The fitting surface between the claw member and the locking member is provided with a tapered inclination in the circumferential direction of the nozzle body,
The long nozzle according to claim 6, wherein the nozzle head and the nozzle body are fastened and fixed when the claw member and the locking member are fitted together.   The long nozzle according to any one of claims 6 to 7, wherein the pair of the claw member and the locking member are arranged at an equal angle based on the number of the installed members, and disposed at a plurality of locations.   The nozzle head is a porous ring integrally formed by gripping at least the porous material in a ring shape with a generally U-shaped gripping material and projecting the socket in a radial direction from the outer peripheral surface of the gripping material. The long nozzle as described in any one of Claims 1-8.   The long nozzle according to claim 9, wherein a lower end surface of the porous ring and an upper end surface of the nozzle body are in close contact with each other.   The long nozzle according to any one of claims 9 to 10, wherein the porous material is exposed on an inner peripheral surface of the porous ring. The gripping material has an upper flat part and a lower flat part that constitute a flat surface parallel to each other facing up and down across the porous material,
The radial length of the upper flat portion is larger than the radial length of the lower flat portion,
The long nozzle according to claim 11, wherein a part of the surface of the porous material exposed on the inner peripheral surface of the porous ring is exposed continuously to the upper flat portion and the lower flat portion.

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