Upper nozzle removal device

Abstract

To provide an upper nozzle pull-out device capable of reducing an unintended load applied to a pull-out rod, etc.SOLUTION: An upper nozzle pull-out device comprises a pull-out rod 11 which is inserted into an upper nozzle 3, and a sliding rod 12 in which one end part 121 is connected to a drive device 44 and has an inclined surface 122. The pull-out rod 11 has a rod body 111, and an abutting rod 112 inserted from a base end part of the rod body and fixed to the rod body in a manner not to move in a longitudinal direction. A rod through-hole 111b through which a sliding rod 12 passes is disposed on a side surface of the rod body 111, and when the sliding rod 12 passes through the rod through-hole 111b, a tip part of the abutting rod 112 and the inclined surface 122 of the sliding rod can abut on each other.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to an upper nozzle removal device for removing an upper nozzle installed at the bottom of a molten metal container. [Background technology]

[0002] An upper nozzle is installed at the bottom of a molten metal container such as a ladle or a tundish as a nozzle for discharging molten metal, and a sliding device is installed below this upper nozzle to adjust the flow rate of molten metal flowing out of the molten metal container. When servicing this sliding nozzle device, the upper nozzle installed at the bottom of the molten metal container may need to be replaced.

[0003] Conventionally, for replacing the upper nozzle, an extraction device has been used, for example, as disclosed in Patent Document 1. In the extraction device of Patent Document 1, a drive direction converter including a stand, a rod holder, and a cotter is attached to the extraction rod in order to convert the vertical propulsive force of the drive device provided on the upper side of the sliding nozzle device into a propulsive force in the direction of extracting the upper nozzle. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 6461574 Summary of the Invention [Problem to be solved by the invention]

[0005] When transmitting propulsive force via a drive direction converter including a stand, rod holder, and cotter, as in the extraction device of Patent Document 1, if the rod holder and cotter are not installed correctly, unintended loads may be applied to the extraction rod, etc., which may cause the extraction rod, etc. to deform.

[0006] The problem to be solved by the present invention is to provide an upper nozzle removal device that can reduce unintended loads applied to the removal rod, etc. [Means for solving the problem]

[0007] According to one aspect of the present invention, there is provided the following upper nozzle removal device. An upper nozzle removal device for removing an upper nozzle installed at the bottom of a molten metal container, comprising: A drawing rod inserted into the upper nozzle; a sliding rod having an inclined surface and one end connected to the driving device; The extraction rod has a rod body and an abutment rod that is inserted from a base end of the rod body and fixed to the rod body so as not to move in the longitudinal direction of the rod body, A rod through hole through which the sliding rod passes is provided on a side surface of the rod body, When the sliding rod passes through the rod through hole, the tip of the abutment rod and the inclined surface of the sliding rod can abut against each other. Effect of the Invention

[0008] According to the upper nozzle extraction device of the present invention, unintended loads applied to the extraction rod, etc. can be reduced. [Brief description of the drawings]

[0009] [Figure 1] FIG. 2 is a perspective view showing a state in which the upper nozzle removal device according to one embodiment of the present invention is used. [Figure 2A] FIG. 2 is a perspective view of the molten metal container and the sliding nozzle device shown in FIG. 1 with some parts omitted. [Figure 2B] FIG. 2 is a front view of the molten metal container and the sliding nozzle device shown in FIG. 1 with some parts omitted. [Figure 3A] FIG. 2 is a front view of an upper nozzle removal device according to an embodiment of the present invention. [Figure 3B] FIG. 2 is an exploded perspective view of an upper nozzle removal device according to an embodiment of the present invention. [Figure 4] Cross-sectional view of FIG. 2B. [Diagram 5] FIG. 4 is an enlarged perspective view of the tip end side of the extraction rod of the upper nozzle extraction device. [Figure 6] The upper nozzle extraction device stand is seen from three different directions. [Figure 7] FIG. 4 is a cross-sectional view showing a state in which the removal rod of the upper nozzle removal device is inserted into the upper nozzle. [Figure 8] FIG. 4 is a cross-sectional view showing a state in which the upper nozzle removal device is attached to the upper nozzle (at the start of a first removal operation). [Figure 9] FIG. 11 is a cross-sectional view showing a state during a first extraction operation. [Figure 10] FIG. 11 is a cross-sectional view showing a state at the end of a first extraction operation. [Figure 11] FIG. 11 is a cross-sectional view showing a state at the start of a second extraction operation. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Fig. 1 is a perspective view showing an upper nozzle removal device according to one embodiment of the present invention in use. Fig. 2A and Fig. 2B show a molten metal container and a sliding nozzle device in Fig. 1 with parts omitted. The upper nozzle removal device 1 is used to remove the upper nozzle 3, which is installed at the bottom of a ladle 2, which is a container for molten metal, from the outside of the ladle 2. A sliding nozzle device 4 is installed below the upper nozzle 3.

[0011] The sliding nozzle device 4 includes a fixed frame 41 fixed to the bottom of the ladle 2, a sliding frame 42 slidably (slidably) and openably / closably provided on the fixed frame 41, and two spring boxes 43 openably / closably provided on the fixed frame 41. The spring boxes 43 are provided with springs for applying surface pressure. In addition, when the sliding nozzle device 4 is in use, the fixed frame 41 holds and fixes an upper plate, and the sliding frame 42 holds and fixes a lower plate, and the upper plate of the sliding nozzle device 4 is connected to the base end of the upper nozzle 3. Furthermore, the fixed frame 41 is provided with a hydraulic cylinder 44 as a drive device for linearly sliding the sliding frame 42 (lower plate) relative to the fixed frame 41 (upper plate). That is, in this specification, the sliding direction of the plate is the direction of the arrow A shown in FIG. 2B. In addition, in FIG. 2A and FIG. 2B, the ladle 2 and the sliding frame 42 and two spring boxes 43 of the sliding nozzle device 4 in FIG. 1 are omitted.

[0012] The upper nozzle extraction device 1 is used by installing it in the fixed metal frame 41 with the sliding nozzle device 4's sliding metal frame 42 in an open state as shown in Fig. 1. When installing the upper nozzle extraction device 1 in the fixed metal frame 41, the upper plate held and fixed to the fixed metal frame 41 is removed. Here, the operation of opening and closing the sliding metal frame 42 of the sliding nozzle device 4 is performed with the sliding nozzle device 4 standing vertically, so Figs. 1, 2A and 2B also show the sliding nozzle device 4 standing vertically. The same applies to Figs. 4 and 7 to 11 described below.

[0013] A specific configuration of the upper nozzle removal device 1 will now be described. Fig. 3A shows a front view of the upper nozzle removal device 1, and Fig. 3B shows an exploded perspective view of the upper nozzle removal device 1. Also, Fig. 4 shows a cross section taken along the line BB in Fig. 2B. The upper nozzle extraction device 1 includes an extraction rod 11, a sliding rod 12, a stand 13, and a positioning rod .

[0014] The extraction rod 11 has a rod body 111 inserted into the upper nozzle 3, and a contact rod 112 inserted from the base end of the rod body 111. The inside of the base end side of the rod body 111 is a hollow portion 111a, and the inner circumferential surface of the hollow portion 111a is a female screw portion. On the other hand, the tip side of the contact rod 112 is a male screw portion. Therefore, by screwing the tip portion of the contact rod 112 from the base end of the rod body 111 into the hollow portion 111a, the contact rod 112 is inserted from the base end of the rod body 111 and is fixed to the rod body 111 so as not to move in the longitudinal direction of the rod body 111. Furthermore, by adjusting the screwing amount of the contact rod 112, the fixed position of the contact rod 112 in the longitudinal direction of the rod body 111 can be changed. The male screw portion of the contact rod 112 is a trapezoidal screw. A trapezoidal thread is preferable for the threaded portion of the abutment rod 112 because it has little backlash and high strength. A circular handle 113 is attached to the base end side of the abutment rod 112, and a rotating grip 114 is attached to the base end of the abutment rod 112. Therefore, when an operator holds the rotating grip 114 and turns the handle 113, the abutment rod 112 advances and retreats along the longitudinal direction of the rod main body 111, so that the fixed position of the abutment rod 112 in the longitudinal direction of the rod main body 111 can be easily changed. In this specification, the tip side of the extraction rod (rod main body and abutment rod) refers to the front side in the direction of insertion into the upper nozzle, and the base side refers to the rear side in the direction of insertion into the upper nozzle.

[0015] A rod through hole 111b through which the sliding rod 12 passes is provided on the side surface of the rod main body 111. The rod through hole 111b is continuous with the above-mentioned hollow portion 111a. In addition, a rod attachment portion 111c for attaching the positioning rod 14 is provided on the side surface of the rod main body 111.

[0016] FIG. 5 shows an enlarged view of the tip side of the rod main body 111. An engagement part 111d and a magnet 111e are provided at the tip of the rod main body 111. The engagement part 111d can rotate around a rotation shaft 111f attached to the tip of the rod main body 111, and is normally held in a position where the longitudinal direction of the engagement part 111d is aligned with the longitudinal direction of the rod main body 111 by the magnetic force of the magnet 111e, as shown in FIG. 5(a). In this state of FIG. 5(a), the rod main body 111 is inserted into the upper nozzle. That is, if the engagement part 111d is in the position shown in FIG. 5(a), it does not get in the way when the rod main body 111 is inserted into the upper nozzle. Therefore, in the following description, the position of FIG. 5(a) is referred to as the "insertion position." On the other hand, when the rod body 111 is inserted into the upper nozzle and its tip penetrates the upper nozzle, the magnet 111e is exposed to high temperature, and the magnetic force of the magnet 111e is reduced due to temperature change, i.e., temperature rise. Then, the engaging portion 111d rotates by its own weight, and as shown in FIG. 5(b), the longitudinal direction of the engaging portion 111d is displaced to a position perpendicular to the longitudinal direction of the rod body 111. That is, since the center of gravity of the engaging portion 111d is located on the tip side of the rotation axis 111f, when the magnetic force of the magnet 111e is reduced, the engaging portion 111d rotates by its own weight and displaces to the position shown in FIG. 5(b). When the engaging portion 111d is displaced to the position shown in FIG. 5(b) in this way, the engaging portion 111d becomes able to engage with the tip of the upper nozzle. Therefore, in the following description, the position of FIG. 5(b) is referred to as the "engaged position." Here, it is preferable that the magnet 111e has a high Curie temperature. If the Curie temperature is low, the magnetic force of the magnet 111e may decrease and the engaging portion 111d may be displaced to the engaged position before the tip of the rod main body 111 penetrates the upper nozzle. Also, if the magnet 111e is used at a temperature exceeding its Curie temperature, the magnetic force will not return to its original state. From these points of view, it is preferable that the magnet 111e has a high Curie temperature, and it is preferable to use, for example, a samarium cobalt magnet (Curie temperature = about 700°C to about 800°C) or an alnico magnet (Curie temperature = about 850°C).

[0017] As shown in FIG. 4, the sliding rod 12 has a connection part 121, which is one end part, detachably connected to the tip part of the cylinder rod 441 of the hydraulic cylinder 44, and slides along the direction A, which is the same as the sliding direction of the plate, by driving the hydraulic cylinder 44. The sliding rod 12 also has an inclined surface 122 inclined in the direction along the sliding direction A. When the upper nozzle 3 is pulled out, the sliding rod 12 is attached so as to penetrate the rod through hole 111b of the rod main body 111 as shown in FIG. 4. When the sliding rod 12 penetrates the rod through hole 111b, the tip part of the abutting rod 112 and the inclined surface 122 of the sliding rod 12 can abut against each other. That is, when the sliding rod 12 penetrates the rod through hole 111b, the inclined surface 122 of the sliding rod 12 is positioned within the rod through hole 111b, which is continuous with the above-mentioned hollow part 111a. 3B, the longitudinal width W1 of the rod through hole 111b is made sufficiently wider than the width W2 of the portion having the inclined surface 122 of the sliding rod 12. The tip of the abutment rod 112 is spherical or curved, and the tip of the abutment rod 112 abuts against the inclined surface 122 of the sliding rod 12 by point contact. Here, since the rod through-hole 111b is provided on the side surface of the rod main body 111, when the sliding rod 12 penetrates the rod through-hole 111b, the longitudinal direction of the rod main body 111 is perpendicular to the longitudinal direction of the sliding rod 12, i.e., the sliding direction A of the sliding rod 12. In addition, as shown in FIG. 4, the sliding center line C of the hydraulic cylinder 44 is located between the inclined surface 122 of the sliding rod, which is the abutment portion with the tip end of the abutment rod 112, and the back surface 123 of the sliding rod, which is the contact portion with the support surface 132 of the frame 13.

[0018] FIG. 6 shows the base 13 from three different directions. The base 13 has an engagement pin 131 for mounting to the fixed metal frame 41, and is attached to the fixed metal frame 41 so as to cover the base end of the upper nozzle 3 by engaging the engagement pin 131 with a pin engagement hole 411 provided on the fixed plate mounting surface of the fixed metal frame 41 as shown in FIG. 4. The base 13 has a support surface 132 that supports the sliding rod 12 in surface contact with the back surface 123 of the sliding rod 12 to support the sliding rod 12 that penetrates the rod through hole 111b of the rod main body 111. Here, the back surface 123 of the sliding rod 12 refers to the surface opposite to the inclined surface 122 of the sliding rod 12. The base 13 also has a guide groove 133 and a guide hole 134 as a guide portion for guiding the sliding of the sliding rod 12 in the A direction. The guide groove 133 and the guide hole 134 are continuous with the support surface 132, and are arranged at intervals along the sliding direction A of the sliding rod 12. Furthermore, the base 13 has a rod insertion part 135 in the center thereof, through which the extraction rod 11 is inserted. When the upper nozzle 3 is extracted, the extraction rod 11 is inserted into the upper nozzle 3 via the rod insertion part 135. The base 13 also has a groove-shaped rod holding part 136 for holding and positioning the positioning rod 14 attached to the rod attachment part 111c of the rod main body 111.

[0019] Next, a method for extracting the upper nozzle 3 by the upper nozzle extraction device 1 will be described. First, as shown in FIG. 7, the engaging pin 131 of the base 13 is engaged with the pin engaging hole 411 of the fixed metal frame 41 to attach the base 13 to the fixed metal frame 41, and the rod body 111 of the extraction rod 11 is inserted into the upper nozzle 3. Next, as shown in FIG. 3A, the positioning rod 14 is attached to the rod mounting portion 111c of the rod body 111, and the positioning rod 14 is held by the rod holding portion 136 to position the rod body 111 on the side surface of the base 13. This positioning determines the position of the rod body 111 in the rotation direction around the longitudinal axis and the longitudinal direction. That is, the position of the rod body 111 in the rotation direction around the longitudinal axis is a position where the engaging portion 111d can rotate by its own weight and be displaced to the engaged position, and the through hole 111b is oriented along the sliding direction A of the sliding rod 12, as shown in FIG. 5(b). In addition, the longitudinal position of the rod body 111 is a position where the engaging portion 111d engages with the tip of the upper nozzle, and a position where the sliding rod 12 can penetrate the through hole 111b. After the rod body 111 of the extraction rod 11 is positioned in this way, the sliding rod 12 penetrates the through hole 111b. Specifically, as shown in FIG. 8, the sliding rod 12 penetrates until the base end side of the inclined surface 122 of the sliding rod 12 is positioned within the through hole 111b. Thereafter, the abutment rod 112 is advanced to bring the tip of the abutment rod 112 into contact with the inclined surface 122 of the sliding rod 12. Specifically, in this embodiment, the operator holds the rotating grip 114 and turns the handle 113 to advance the abutment rod 112. In this way, by using the handle 113, the abutment rod 112 can be easily advanced, and the inertial force caused by the rotation of the handle 113 can ensure that the tip of the abutment rod 112 abuts firmly and securely against the inclined surface 122 of the sliding rod 12.

[0020] 9 and 10, the hydraulic cylinder 44 is driven to slide the sliding rod 12 in the direction A1 on one side of the sliding direction A. At this time, since the tip of the abutting rod 112 abuts against the inclined surface 122 of the sliding rod 12, the propulsive force of the hydraulic cylinder 44 in the A1 direction is converted into a propulsive force in the direction in which the upper nozzle 3 is pulled out, that is, in the direction D shown in Figs. 9 and 10, and the upper nozzle 3 can be pulled out by this propulsive force in the direction D.

[0021] As described above, according to this embodiment, the tip of the abutting rod 112 abuts against the inclined surface 122 of the sliding rod 12, so that the thrust of the hydraulic cylinder 44 can be transmitted in the direction of extracting the upper nozzle 3, and the thrust of the sliding rod 12 can be transmitted directly to the extraction rod 11, so that the unintended load on the extraction rod 11 can be reduced. In addition, as described in FIG. 4, the sliding center line C of the hydraulic cylinder 44 is located between the inclined surface 122 of the sliding rod 12, which is the abutting portion with the tip of the abutting rod 112, and the back surface 123 of the sliding rod 12, which is the contact portion with the support surface 132 of the base 13, so that the bending force applied to the sliding rod 12 can be reduced. Furthermore, in this embodiment, the back surface 123 of the sliding rod 12 slides while making surface contact with the support surface 132 of the base 13, so that the sliding rod 12 can slide smoothly. In order to prevent gaps or rattles from occurring between the back surface 123 of the sliding rod 12 and the support surface 132 of the base 13 during sliding, a magnet can be placed on the back surface 123 of the sliding rod 12 or on the support surface 132 of the base 13. In this embodiment, the base 13 is attached so as to cover the base end of the upper nozzle 3, so that the upper nozzle 3 can be safely removed.

[0022] The upper nozzle extraction device 1 of this embodiment has fewer parts and smaller parts than the extraction device of Patent Document 1. That is, the upper nozzle extraction device 1 of this embodiment is substantially composed of three parts, an extraction rod 11, a sliding rod 12, and a stand 13, and the weight of each part is about 7 kg at maximum. Therefore, an operator can assemble and disassemble the parts by holding them without using a jig such as a balancer, and the upper nozzle extraction device 1 of this embodiment has excellent handling and operability. Furthermore, the upper nozzle extraction device 1 of this embodiment has fewer parts that come into contact with each other than the extraction device of Patent Document 1, so there is an advantage that the frictional force acting on the parts is reduced and the parts are less likely to break.

[0023] 10, the tip end 111b-1 of the rod through hole 111b is located on the tip side of the support surface 132 of the stand 13, in other words, the back surface 123 of the sliding rod 12. This allows the extraction rod 11 to move without any problems in the extraction direction (direction D) of the upper nozzle 3 during the extraction operation.

[0024] If the upper nozzle 3 cannot be extracted by one extraction operation shown in Figs. 8 to 10, a second extraction operation can be performed. Fig. 11 shows the state at the start of the second extraction operation. That is, this state is a state in which the contact rod 112 is retracted and the sliding rod 12 is slid toward the other side A2 of the sliding direction A from the state at the end of one extraction operation shown in Fig. 10, and then the contact rod 112 is advanced so that the tip of the contact rod 112 is in contact with the inclined surface 122 of the sliding rod 12. The advancement and retreat of the contact rod 112 at this time can also be easily performed by the operator by holding the rotating grip 114 and turning the handle 113. Then, the second extraction operation can be performed by driving the hydraulic cylinder 44 to slide the sliding rod 12 toward the one side A1 of the sliding direction A from the state shown in Fig. 11. In this embodiment, in order to reliably perform a second pulling-out operation if necessary, the end 111b-1 on the tip side of the rod through hole 111b is designed to be positioned further tip-side than the support surface 132 of the stand 13, in other words, the back surface 123 of the sliding rod 12, even at the end of the second pulling-out operation.

[0025] As described above, in this embodiment, the sliding rod 12 is slid in the direction of one side A1 of the sliding direction A to perform the extraction operation, but the sliding rod 12 can also be slid in the direction of the other side A2 of the sliding direction A to perform the extraction operation. In this case, the direction of the inclined surface 122 of the sliding rod 12 is reversed from that of this embodiment. In this embodiment, the hydraulic cylinder 44, which is the drive device of the sliding nozzle device 4, is used as the drive device for sliding the sliding rod 12. However, this hydraulic cylinder 44 may be fixed to the maintenance site in advance, or may be installed in the sliding nozzle device 4. In this embodiment, the hydraulic cylinder 44, which is the drive device of the sliding nozzle device 4, is located on the upper side when the sliding rod 12 is erected vertically in the maintenance site, but it may also be located on the lower side. In this case, the extraction operation can also be performed by sliding the sliding rod 12 with the hydraulic cylinder 44. In addition, in this embodiment, the magnet 111e is provided to control the rotation of the engagement portion 111d, but instead of the magnet 111e, for example, air pressure or hydraulic pressure can be used. When air pressure or hydraulic pressure is used to rotate the engagement portion 111d, a pressing device connected to an air pressure cylinder or hydraulic cylinder may be used at the tip of the rod main body 111. Using air pressure or hydraulic pressure, the pressing device can press the engagement portion 111d to rotate the engagement portion 111d. [Explanation of symbols]

[0026] 1 Upper nozzle removal device 11 Extraction rod 111 Rod body 111a Cavity 111b Rod through hole 111b-1 End portion on the tip side of the rod through hole 111c Rod attachment part 111d Engagement part 111e Magnet 111f Rotation axis 112 Contact rod 113 Handle 12 Sliding rod 121 Connection part (one end) 122 Slope 123 Back 13 Mounting stand 131 Engagement pin 132 Support surface 133 Guide groove (guide part) 134 Guide hole (guide part) 135 Rod insertion part 136 Rod holder 14 Positioning rod 2 Ladle (molten metal container) 3 Upper nozzle 4. Sliding nozzle device 41 Fixed Gold Frame 411 Pin engagement hole 42 Slide Gold Frame 43 Spring Box 44 Hydraulic cylinder (drive unit) 441 Cylinder Rod

Claims

1. An upper nozzle removal device for removing an upper nozzle installed at the bottom of a molten metal container, comprising: A drawing rod inserted into the upper nozzle; a sliding rod having an inclined surface and one end connected to the driving device; The extraction rod has a rod body and an abutment rod that is inserted from a base end of the rod body and fixed to the rod body so as not to move in the longitudinal direction of the rod body, A rod through hole through which the sliding rod passes is provided on a side surface of the rod body, an upper nozzle removal device, wherein when the sliding rod passes through the rod through hole, the tip of the abutment rod and the inclined surface of the sliding rod can abut against each other.

2. The upper nozzle removal device according to claim 1 , wherein a fixed position of the abutment rod relative to the rod body is changeable.

3. Further comprising a stand for supporting the sliding rod, The upper nozzle removal device according to claim 1 or 2, wherein a back surface of the sliding rod is in surface contact with a support surface of the stand.

4. The upper nozzle removal device according to claim 3 , wherein at the end of the removal operation, a tip end of the rod through hole is positioned tip side of a support surface of the base.

5. The tip of the rod body is provided with an engagement portion and a magnet that can be engaged with the upper nozzle, 5. The upper nozzle removal device according to claim 1, wherein the engaging portion is capable of rotating by its own weight when the magnetic force of the magnet is reduced due to a temperature change.

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