JP4866270B2 - Sliding nozzle device and plate used in the device - Google Patents

Description

  The present invention relates to a sliding nozzle device used for controlling a flow of molten steel flowing out from a container such as a ladle or a tundish in continuous casting of steel, and a plate used in the device.

  In general, the sliding nozzle device is composed of a plurality of refractory plates, respective storage metal frames for fixing and holding them, a drive device for driving the storage metal frames, and a surface between the plates. Pressure applying means for applying pressure. Then, the flow of molten steel is controlled by sliding the plate relatively and opening and closing the nozzle holes. During use, a large pressure is applied between the surfaces of the plates to prevent leakage of molten steel from the gaps between the plates. It has been applied. In the sliding nozzle device, each plate is fixedly held by a storage metal frame. In general, the plate is mainly composed of a plate brick having nozzle holes, and the side of the plate is fastened with a metal band, or the type in which a metal box-shaped case is mounted.

  As an example of the sliding nozzle device, as shown in FIG. 7, an upper plate 72 and a lower plate 75 and a fixed member that is installed under the upper nozzle provided at the bottom of the molten metal container 71 and holds the upper plate 72. A metal frame 73, an open / close metal frame 74 that is openable / closable with respect to the fixed metal frame 73, and a slide metal frame 76 that holds a lower plate 75 provided between the fixed metal frame 73 and the open / close metal frame 74. The lower plate 75 includes an elastic body (not shown) that presses the lower plate 75 against the upper plate 72, and a drive device 79 for sliding the slide metal frame 76. By sliding the slide metal frame 76, the flow rate of the molten metal is adjusted by adjusting the degree of opening depending on the positions of the nozzle holes 77 and 78 formed in the upper plate 72 and the lower plate 75, respectively. The upper and lower plates 72 and 75 are fixedly held by a fixed metal frame 73 and a slide metal frame 76 as storage metal frames, respectively. Further, there are a type using three plates, a type in which the lower nozzle and the lower plate are integrated, and a type in which the lower plate and the immersion nozzle are integrated.

  In these sliding nozzle devices, there are a vertical pressing method and a horizontal pressing method as means for fixing the plate to the plate receiving metal frame. Among these, the vertical pressing method is mainly intended to prevent displacement with respect to the sliding force of the plate. However, since the plate becomes hot at the time of use and expands, the press in the longitudinal direction acts as a compressive force on the plate, which may cause a large crack extending in the longitudinal direction on the plate. For this reason, the generation of cracks has a problem that the plate having the cracks must be replaced with a new plate, resulting in high costs.

  Patent Document 1 is a method in which the vertical press and the horizontal press are simultaneously performed in order to prevent the occurrence of cracks in the longitudinal direction, which is a defect of the vertical press, and the horizontal press gives a pressing force to the other by a cotter method. ing. It is considered that this structure has an effect of suppressing the occurrence of cracks in the longitudinal direction from the nozzle holes by suppressing the occurrence of cracks in the longitudinal direction due to the pressing in the longitudinal direction with the pressing force in the width direction. Thus, normally, the horizontal press is used in combination with the vertical press in order to compensate for the defect of only the vertical press.

Further, Patent Document 2 is an embodiment applied to a fireproof plate having a curved outer circumference circle, and holding metal fittings arranged around an elliptical or oval fireproof plate are linked to each other with pins, By applying a tensile force to the link connection, the pressing metal can fasten and fix the fireproof plate from multiple directions. The fireproof plate can be tightened and fixed from multiple directions with a small number of pulling devices, and the work is simple and can be done in an extremely short time. The structure is simple and does not require a multiple-direction tightening mechanism, unlike conventional devices. There is no risk of creating parts. Further, it is described that the tightening is performed almost uniformly over the entire circumference of the refractory plate, so that it has an advantage that local stress can be reduced as compared with the conventional method.
JP 2000-233274 A Japanese Utility Model Publication No. 56-131966

  In the method of Patent Document 1, labor is required for attachment and detachment, workability is poor, and cracks generated from the center of the nozzle hole of the plate cannot be completely suppressed. In the method of Patent Document 2, for example, if the entire side surface of the plate is covered with the chain, the chain may be extended by the force that the chain receives from the plate when the nozzle hole is opened and closed. If the chain extends, the plate bricks will be displaced, creating gaps at the connection with the upper and lower nozzles, and there is a risk of steel leakage. Further, the refractory itself may be cracked at the fitting portion with the upper nozzle and the lower nozzle.

  A problem to be solved by the present invention is to suppress the occurrence of cracks around the nozzle hole during use by fixing the plate with a uniform force, and a sliding nozzle device capable of improving the durability of the blade and It is to provide a plate for use in this device.

  It is another object of the present invention to provide a sliding nozzle device and a plate used in the device that can prevent the chain from being stretched and the plate being displaced due to the plate being fastened and fixed by the chain.

The present invention relates to a sliding nozzle device including a plate and a plate storage metal frame for fixing and holding the plate, wherein the plate storage metal frame is provided on a side opposite to the plate, and the receiving block is in contact with the side surface of the plate. and comprising a chain fixed block, a chain provided between the block and the chain fixed block receives, and the chain presser means for pressing the chain Ru to generate a clamping force of the chain between the chain fixing block and the plate It is characterized by that.

Chains, two are provided, each chain receiving is fixed to the block and the chain fixing blocks pivotably chain presser means comprises a pressing portion for pressing the chain between the plate and the chain fixing block, retainer And a pressing means for pressing the part against the chain.

  The plate has an elliptical outer shape in plan view, and the outer shape in plan view is composed of a line including a curve with a radius of curvature r on both sides of the longitudinal axis and a curve with a radius of curvature R on both sides of the longitudinal axis and the vertical direction. When the diameter of the hole is D, it is possible to satisfy D <r <3D and 3r <R <8r.

  The sliding nozzle device of the present invention can prevent the elongation of the chain and the displacement of the plate due to the chain, so that the plate is fixed with a uniform force by the tightening force of the chain, thereby suppressing the occurrence of cracks around the nozzle hole during use. Therefore, the durability of the brate can be improved.

  Further, the plate of the present invention can prevent cracks when the plate is used because a force directed toward the inside of the plate is generated on almost the surface in contact with the chain by tightening the side surface of the plate with the chain.

  FIG. 1 shows a plan view of an embodiment of a plate receiving metal frame used in the sliding nozzle device of the present invention and a plate stored therein. 2 is a view taken along the line AA in FIG. 1, and FIG. 3 is a view taken along the line BB in FIG.

  In FIG. 1, an elliptical plate 1 is held and fixed at substantially the center of the plate receiving metal frame 2. The outer shape of the plate storing metal frame 2 is a long rectangle in plan view. A front wall 21 and a rear wall 22 are connected to the peripheral edge in the sliding direction, and a lateral wall 23 is connected to each side.

The plate 1 is fixedly held on the plate receiving metal frame 2 by tightening almost the entire side surface in the lateral direction by two chains 3 symmetrical with respect to the longitudinal axis of the plate 1. A receiving block 5 for positioning the plate 1 and a chain fixing block 4 on the other end side are attached to both sides of the plate 1 in the longitudinal direction, and the ends of the chain 3 are held so as to be rotatable.

  The receiving block 5 has an arcuate abutment surface 51 with which one side surface abuts in the longitudinal axis direction of the plate 1, and rotatably holds the rotation shaft of the chain 3 at both ends of the abutment surface 51. The opposite side of the contact surface 51 is fixed to the rear wall 22 of the plate receiving metal frame 2 by two bolts 52. The side surface of the plate 1 in the longitudinal axis direction contacts the contact surface 51 of the receiving block 5, and the position of the plate 1 can be determined. Further, since the longitudinal force can be received from the plate 1, it is possible to prevent the chain 3 from being stretched due to an excessive force applied to the chain 3. In this embodiment, the two chains 3 are fixed to the receiving block 5 so as to be rotatable. However, a single chain can also be used. In this case, it is possible to adopt a structure in which the chain is slidably held by the receiving block. For example, the receiving block may be provided with grooves, rollers, etc., and the chain may be slidably held.

  The length of the contact surface 51 of the receiving block 5 can be in the range of 10 mm or more and less than 100 mm. Similarly, it is sufficient that the distance between the two chain holding portions 53 that hold the two chains 3 rotatably is 10 mm or more and less than 100 mm. If it exceeds 100 mm, the tightening force of the chain 3 on the side surface of the plate 1 will be small, and if it is less than 10 mm, the receiving area will be small and the stress generated on the plate will be large, so that the durability may be insufficient. In this way, the side surface of the plate 1 abuts against the receiving block 5, so that even when a force is applied to move the plate to the right when sliding in FIG. 1, the receiving block 5 receives this force. And the displacement of the plate can be prevented.

The chain fixing block 4 is disposed on the plate longitudinal axis on the opposite side of the receiving block 5 with the plate 1 interposed therebetween and further away from the end face of the plate 1. As shown in FIG. 4, the chain fixing block 4 includes a fixing portion 41 having a T-shape in plan view, and a moving pin 44 that is movably fitted into a through hole of a fixing plate 42 provided at the center of the fixing portion 41. It consists of. The moving pin 44 has a chain holding terminal 46 at one end of the bolt part 45, and the bolt part has a male screw groove. The chain holding terminals 46 hold the rotation axes of the two chains 3 so as to be rotatable . The distance between the rotation axes of the two chains 3 held here is 20 mm. The bolt portion 45 of the moving pin 44 is fitted into the through hole of the fixed plate 42 and the nut 47 is screwed on the opposite side. By rotating the nut 47, the moving pin 44 moves, and the chain 3 can be positioned and fixed. The fixing portion 41 is fixed to the front wall 21 by screwing two fixing bolts 48 penetrating the front wall 21 on both sides of the side wall side.

  In the chain fixing block 4, if the distance between the chains 3 held by the chain holding portion 46 is too large, the contact surface of the chain 3 with the plate 1 is reduced, so that it can be 10 mm or more and less than 100 mm. The distance between the chain holding terminal 46 of the chain fixing block 4 and the end surface of the plate 1 can be set to 20 to 100 mm. If it exceeds 100 mm, the plate storage metal frame 2 becomes large, and it becomes difficult to handle. If it is less than 20 mm, the pressing force is insufficient.

  The chain fixing block only needs to be able to fix and hold the chain, and similarly to the receiving block, one chain can be slidably held. As a result, it is possible to use a chain in a single ring.

  The two chains 3 held by the chain fixing block 4 are in contact with the two rollers 64 as the pressing portions 61 of the chain pressing means 6 between the chain fixing block 4 and the plate 1. Tension is applied by pressing inward (in the plate direction). The chain pressing means 6 includes a pressing portion 61 for contacting the chain 3 and a pressing portion 62 for applying a pressing force. The pressing portion 61 includes a roller 64 that can contact the chain 3, and a roller holding portion 65 that rotatably supports the roller 64 on a rotation shaft 63. A plurality of magnets 69 are embedded in the roller 64. In this embodiment, the pressing portion 61 is a roller. However, the structure is not particularly specified as long as it can be pressed in contact with the chain.

  In this embodiment, since the roller 64 is used, the contact area with the chain 3 is large, and the frictional resistance with the chain 3 is reduced, so that a sufficient pressing force can be obtained with a small force of tightening the nut and moving the bolt. Obtainable. In this way, by pressing each chain 3 inward with the chain pressing means 6, the vertical pressing and the horizontal pressing can be applied simultaneously. And even if the force which moves to the left direction acts on a plate at the time of sliding in FIG. 1, this force can be received by the press part 61 and the effect which prevents the shift | offset | difference of a plate can also be acquired. Further, by releasing the pressing of the chain pressing means 6, the chain is loosened and a space is formed between the plate brick and the chain fixing block, so that the plate brick can be easily attached and detached.

  Further, the chain tightens the side surface of the plate between the receiving block with which one side surface in the longitudinal axis direction of the plate abuts and the chain fixing block provided on the opposite side of the receiving block. For this reason, compared to the conventional lateral pressing method, the plate can be pressed in the horizontal direction with a uniform force over a higher range, and the effect of preventing longitudinal cracks when using the plate is very excellent. It will be a thing.

  The roller holding portion 65 includes an upper plate 66 for supporting the rotating shaft 63 of the roller 64 at a substantially right angle with respect to the sliding surface of the plate 1, a lower plate (not shown), and a side wall (not shown) for connecting them. . A pressurizing part 62 is connected to the side wall. Further, a magnet 69 is embedded in the roller. When the tightening force of the chain 3 is weakened by these magnets 69, the chain 3 sticks to the magnets 69 so as not to obstruct plate replacement.

  The pressurizing unit 62 includes one tightening bolt 67 and two nuts 68 each having a thread groove on the front wall 21 side of the plate receiving metal frame 2. The fastening bolts 67 are fitted into the through holes of the front wall 21 and the chain fixing block 4, and nuts 68 are screwed on the outer surface side of the rear wall 21 and the inner surface side of the chain fixing block 4. The pressurizing unit 62 can advance and retreat in the plate longitudinal axis direction within the plate receiving metal frame 2 by rotating a nut 68. Further, a gap of about 1 mm is provided between the roller holding portion 65 and the lateral wall 23.

  The pressing unit 62 moves in a direction parallel to the longitudinal axis of the plate 1, but this is not particularly limited as long as it can apply tension to the chain 3. For example, it can also be pressed from the outside in a direction perpendicular to the longitudinal axis of the plate or in the center direction of the nozzle hole.

  The pressurizing unit 62 is not limited to the present embodiment, and a conventional pressurizing unit for fixing the plate, such as a cam mechanism or a cotter mechanism, can also be applied.

  In FIG. 1, the two lateral walls 23 of the plate receiving metal frame have arc-shaped side surfaces so as to surround the side surfaces of the plate 1. A chain 3 is disposed between the plate 1 and the lateral wall 23. A total of six magnets 25 are embedded in the horizontal wall 23 on each side, three on each side.

  Instead of the magnet 25, an elastic body such as a spring may be embedded to connect the elastic body and the chain. Furthermore, using the fact that the longitudinal axis direction of the plate becomes vertical during plate replacement work, a groove or cavity parallel to the longitudinal axis direction of the plate is formed in the lateral wall, and a weight connecting the lines is put therein. A hole or groove opening in the inner hole surface of the lateral wall may be provided in the groove or cavity, and the weight and the chain may be connected by a line.

  As the plate 1 used in the sliding nozzle device of the present invention, a generally used plate can be used. In addition, a round plate with no corners on the side surface is more preferable because a uniform tightening force is generally exerted by tightening with a chain. For example, it is desirable to use an elliptical plate in plan view as in the embodiment of FIG. Here, the elliptical shape means that most parts of the outer shape in the plan view are constituted by curves. Specifically, the length of 60% or more is preferably a curve. By using an elliptical plate, tightening the side of the plate with a chain generates a force toward the inside of the plate on most of the surfaces in contact with the chain, which has the effect of suppressing the occurrence of more vertical cracks. The effect of suppressing the generation | occurrence | production of the crack around a nozzle hole can be acquired more.

  FIG. 5 shows Example 1 of a plate that can be used in the present invention. The outer shape of the plate 1 includes two curves having a radius of curvature r of 65 mm on both sides in the longitudinal direction and two curves having a radius of curvature R of 370 mm on both sides of the longitudinal axis and the vertical direction. It consists of a short straight line. The inner diameter D of the nozzle hole 11 is 35 mm. A straight line S1 connecting the centers of the curvature radii R intersects at a right angle at the center of the straight line S2 connecting the centers of the curvature radii r of the plate 1. A straight line S2 connecting the centers of the curvature radii r coincides with the central axis in the longitudinal direction of the plate 1.

  Thus, the plate 1 includes a curve of the radius of curvature r on both sides in the longitudinal axis direction and a curve of the radius of curvature R on both sides of the longitudinal axis and the vertical direction, and the radius of curvature on both sides of the longitudinal axis direction is r and the direction perpendicular to the longitudinal axis. If the radius of curvature on both sides is R and the diameter of the nozzle hole 11 of the plate 1 is D, then D <r <3D and 3r <R <8r. The straight lines connecting the centers of the curvature radii R can be shaped so as to intersect at substantially right angles within a range of ± 20 mm with respect to the centers of the straight lines connecting the centers of the curvature radii r. By adopting such a shape, the tightening force by the chain can be applied more uniformly as a force from the vertical direction and the horizontal direction toward the center of the plate, so that cracks during use of the plate can be prevented.

  When the radius of curvature r on both sides in the longitudinal axis direction of the plate 1 is equal to or smaller than the diameter D of the nozzle hole 11, the distance between the inner surface of the nozzle hole and the side surface of the plate 1 becomes small, so that the strength is insufficient and the surface extends from the inner surface to the side surface. The crack which becomes easy to enter. When r is 3D or more, the plate 1 becomes too large as necessary, which is uneconomical.

  When the radius of curvature R on both sides of the longitudinal axis of the plate 1 is 3r or less, the length of the plate brick becomes too small for the necessary stroke for sliding the plate 1, and the strength is insufficient. Becomes worse. If R is 8r or more, the plate becomes too large as necessary, which is uneconomical.

  Further, as shown in FIG. 6, the plate as the second embodiment is composed of a curve with a radius of curvature r on both sides in the longitudinal axis direction and a curve with a radius of curvature R on both sides of the longitudinal axis and the vertical direction. If the curvature radius on both sides is r, the curvature radius on both sides in the direction perpendicular to the longitudinal axis is R, and the diameter of the nozzle hole 11 of the plate 1 is D, then D <r <2D and 3r <R <8r. This plate 1 has the object of rotating twice, that is, it has a target shape in front, rear, left and right, and a uniform tightening force can be applied to the side surface of the plate by a chain. Note that r is 65 mm, R is 370 mm, and D is 35 mm.

  Next, a method for fixing and holding the plate 1 to the plate receiving metal frame 2 of the present invention will be described with reference to FIG. Before the plate 1 is accommodated, the chain 3 is fixed to the lateral wall 23 and the roller 64 by a magnet embedded in the lateral wall and the roller 64 to form a space for accommodating the plate 1. Place plate 1 into this space. Next, when the tightening nut 68 of the chain pressing means 6 is tightened, the roller 64 moves in the direction of the plate 1 and contacts the chain. When further tightened, the chain 3 is pushed inward and tension is applied to the entire chain. When the tightening nut 68 is further tightened, the roller 64, the chain 3, and the side surface of the plate 1 come into contact with each other. The tightening does not need to be performed to this limit point, and may be stopped when the optimum tension is generated in the chain 3.

  By pressing the chain between the fixed block and the plate in this way, a part of the force acting on the chain can be received by the pressing means, and the chain can be prevented from extending. The optimum tension can be adjusted with the nut 47. Further, when the roller 64 and the chain 3 are brought into contact with each other or the gap is made small at the time of tightening, the force in the sliding direction of the plate 1 is received by the roller 64 and the displacement of the plate 1 is surely prevented. It is also possible to prevent the chain from being stretched due to excessive force applied to the chain 3. Further, when tension is applied to the chain, the chain tension can also be controlled by rotating the nut 47 of the chain fixing means without moving the chain pressing means as described above.

During use of the plate 1, since the tightening force from the lateral direction acts uniformly by the chain, an effect of preventing the vertical crack of the plate can be obtained. Further, since the force at the time of sliding of the plate 1 can be received by the receiving block 5 and the chain pressing means 6, the chain 3 is not stretched excessively, so that the chain 3 is less stretched.

The top view of the Example of the plate accommodation metal frame by this invention, and the plate accommodated in it AA arrow view in FIG. BB arrow view in FIG. 1 is an enlarged view of the chain fixing block and the chain pressing means in FIG. Explanatory drawing of one Example of the plate of FIG. Explanatory drawing of another Example of the plate of FIG. Explanatory drawing showing an example of a conventional sliding nozzle device

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Plate 11 Nozzle hole 2 Plate storing metal frame 21 Front wall 22 Rear wall 23 Side wall 24 Bottom wall
25 Magnet 3 Chain 4 Chain fixing block 41 Fixing portion 42 Fixing plate 44 Moving pin 45 Bolt portion 46 Chain holding terminal 47 Nut 48 Fixing bolt 5 Receiving block 51 Abutting surface 52 Bolt 53 Chain holding portion 6 Chain holding means 61 Holding portion 62 Pressure unit 63 Rotating shaft 64 Roller 65 Roller holding unit 66 Upper plate 67 Tightening bolt 68 Nut 69 Magnet 71 Molten metal container 72 Upper plate 73 Fixed metal frame 74 Opening and closing metal frame 75 Lower plate 76 Slide metal frame 77 Nozzle hole 79 Drive apparatus

Claims (7)

In a sliding nozzle device having a plate and a metal frame that holds the plate fixedly,
A receiving block in contact with the side surface of the plate, a chain fixing block provided on the opposite side of the plate from the receiving block, a chain provided between the receiving block and the chain fixing block, a chain fixing block, sliding nozzle device which comprises a chain presser means Ru generate a clamping force of the chain presses the chain between the plates. Chains, two are provided, each chain receives a sliding nozzle device according to claim 1, in block and chain fixing blocks are pivotably secured.   The sliding nozzle device according to claim 1 or 2, wherein the chain pressing means includes a pressing portion for pressing the chain and a pressing means for pressing the pressing portion against the chain.   The sliding nozzle device according to claim 1, wherein the plate has an elliptical outer shape in plan view. The plate has an outer shape in plan view composed of a line including a curve with a radius of curvature r on both sides of the longitudinal axis and a curve with a radius of curvature R on both sides of the longitudinal axis and the vertical direction, and the diameter of the nozzle hole of the plate is D. D <r <3D, and 3r <R <sliding nozzle device according to claim 1, wherein the 8r.   The sliding nozzle device according to claim 4 or 5, which is used for continuous casting.   A plate used in the sliding nozzle device according to claim 4, 5 or 6.

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