JP5898348B1 - Molten metal supply structure, casting machine, and manufacturing method of casting - Google Patents

Abstract

In a molten metal supply structure having a chute, damage to the chute is reduced. A molten metal supply structure includes an arc ladle (3) and a chute (5). The ladle body (9) of the arc ladle (3) is a first arc whose first cross-sectional shape is centered on the center (3c), which is the rotation axis, and extends along the rotation axis. Part (9b). The nozzle (10) of the arc ladle (3) is disposed on the bottom surface (9b). [Selection] Figure 1

Description

  The present invention relates to a molten metal supply structure provided with a ladle for pouring molten metal to the outside, a casting machine equipped with the molten metal supply structure, and a method for producing a cast using the caster.

  As a casting machine, as a molten metal supply structure of a casting machine as described in Patent Document 1, a chute having a groove for receiving molten metal poured from a pouring port of a ladle and guiding the received molten metal in a horizontal direction. The one with is known.

  FIG. 8 is a cross-sectional view showing an example of the casting machine according to the conventional example.

  A casting machine 150 shown in FIG. 8 includes a triangular ladle 103 to which a molten metal 102 is supplied from a stationary ladle 101, a motor 104, a chute 105, a trough (groove) 106, a cart unit 107, a cart traveling unit 108, and a cylinder 109. I have. The cart unit 107 includes a mold 110, a sleeve 111, and a mold rotation mechanism 112.

  In the casting machine 150 shown in FIG. 8, when the triangular ladle 103 is tilted, a coating mold (graphite or the like) is applied to the surface of the molten metal 102 in an amount proportional to the tilting angle of the triangular ladle 103. The chute 105 and the trough 106 are passed through and supplied into the mold 110 of the cart unit 107 constituting the casting machine 150.

  In the casting machine 150, the following problems relating to the triangular ladle 103 occur.

  That is, the molten metal 102 stored in the triangular ladle 103 can be mixed with dirt. An example of the plaque is an oxide or sulfide of the molten metal 102. If the dirt flows out from the triangular ladle 103 together with the molten metal 102 and is supplied to the mold 110, the casting may be mixed with the casting and the quality of the casting may be deteriorated. Moreover, if the dirt adheres to the inner wall of the triangular ladle 103, the dirt hinders the flow of the molten metal 102, and there is a possibility that the amount of pouring of the molten metal 102 is not stable.

JP 7-204819 A (published August 8, 1995)

  On the other hand, in the casting machine 150, the following problems relating to the chute 105 occur.

  That is, in the triangular ladle 103, the molten metal 102 is always poured from the vicinity of the fan-shaped center 103c. Moreover, since the center 103c is a rotation axis of the triangular ladle 103, the center 103c is fixed even if the triangular ladle 103 is rotated. As a result, the chute 105 always receives the molten metal 102 poured from the triangular ladle 103 at the same position. As a result, if the thickness of the coating mold applied to the molten metal contact surface on the surface of the chute 105 is thin, image sticking may occur. Therefore, when the coating mold is formed thick, the coating mold is easily peeled off, and when the coating mold is peeled and mixed into the molten metal 102, the quality of the casting may be deteriorated.

  Therefore, the inventors of the present application have made an intensive study and have to devise a new molten metal supply structure for solving the problem related to the chute 105.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a molten metal supply structure capable of reducing damage to the chute in the molten metal supply structure including the chute, and the molten metal supply structure. It is an object of the present invention to provide a casting machine equipped with the casting machine and a method of manufacturing a casting using the casting machine.

  In order to solve the above problems, a molten metal supply structure of the present invention includes a ladle and a chute having a groove for receiving the molten metal poured from the ladle and guiding the received molten metal in a horizontal direction. The ladle is provided with a ladle body for storing the molten metal, and a pouring port for pouring the molten metal stored in the ladle body to the outside. A rotary shaft that rotates the pouring gate in a plane defined by the pouring direction from the ladle body to the outside and the vertical direction, and a cross-sectional shape in a direction parallel to the plane is the rotational shaft. And a bottom surface portion extending along the rotation axis, and the pouring gate is arranged on the bottom surface portion.

  According to said structure, the position of a pouring gate can be changed by rotating a ladle main body. Thereby, the position where the chute receives the molten metal can be appropriately changed according to the rotation angle of the ladle body. As a result, even if the coating mold applied to the molten metal contact surface on the chute surface is not thickly applied, it is possible to suppress the occurrence of seizure on the chute surface and to reduce damage to the chute.

  In the molten metal supply structure of the present invention, in the cross section in the direction parallel to the plane, the angle formed by the pouring direction from the ladle body to the outside and the direction in which the chute guides the molten metal is 90 ° or more and 270. It is preferable that the angle is not more than °.

  According to said structure, since the flow of the molten metal poured from the ladle can change a flow direction largely with a chute | shoot, it is possible to buffer the momentum at the time of the pouring from a ladle. For this reason, the flow of the molten metal supplied from the chute can be stabilized.

  In the molten metal supply structure of the present invention, the chute has a cross-sectional shape in a direction parallel to the plane, the center of which is the rotation axis, and a distance from the first arc to the rotation axis is long. Two arcs are preferred.

  According to said structure, it is easy to make constant the shortest distance of a bottom face part (as a result, pouring gate) and a chute | shoot. By making this shortest distance constant, it is possible to further stabilize the chute from guiding the molten metal.

  Moreover, it is preferable that the width | variety of the said bottom face part in the direction in alignment with the said rotating shaft of the molten metal supply structure of this invention is less than the diameter of the circle | round | yen which has the said 1st circular arc.

  According to said structure, control of the pouring amount of a molten metal becomes easy by making small the width | variety of the ladle main body in the direction perpendicular | vertical with respect to the pouring direction.

  In the molten metal supply structure of the present invention, the pouring spout is constituted by a substantially cylindrical nozzle, and a line segment connecting the rotating shaft and the center of the nozzle in a cross section in a direction parallel to the plane. It is preferable that the axis of the nozzle is disposed above.

  According to said structure, in the said cross section, since the axial center of a nozzle is arrange | positioned on the line segment which connects a rotating shaft and the center of a nozzle, the flow of the molten metal which passes a nozzle can be made smooth. it can.

  Moreover, the casting machine of this invention is equipped with said molten metal supply structure, It is characterized by the above-mentioned.

  According to said structure, in a casting machine, the effect similar to said molten metal supply structure can be acquired.

  The casting production method of the present invention is a casting production method using the above casting machine, wherein the molten metal poured from the ladle is passed through the chute into the cylinder of the casting machine. A molten metal supplying step for supplying the molten mold to the mold, and the molten metal supplying step further rotates the mold around the cylindrical axis of the mold while the chute is used to supply the molten metal to the mold. It is characterized by moving in the direction.

  According to said structure, the casting by which quality degradation was suppressed can be manufactured by using the casting machine of this invention.

  According to the present invention, in the molten metal supply structure provided with a chute, it is possible to stabilize the flow of the molten metal, suppress the deterioration of the casting quality, and reduce the damage to the chute.

It is sectional drawing which shows the structure of the casting machine which concerns on Embodiment 1 of this invention. It is an enlarged view of a ladle and a chute, which is a molten metal supply structure in the casting machine shown in FIG. It is sectional drawing which shows the structure of the casting machine which concerns on Embodiment 2 of this invention, and has shown the mode at the time of casting start. It is sectional drawing which shows the structure of the casting machine which concerns on Embodiment 2 of this invention, and has shown the mode at the time of completion | finish of casting. It is sectional drawing of the ladle and chute of the casting machine shown in FIG. 3 and FIG. (A)-(e) is the figure which showed the height relationship of the pouring opening in the ladle which concerns on this invention, and the liquid level of a molten metal in time series. It is sectional drawing which shows the specific example of a structure of the ladle which concerns on this invention. It is sectional drawing which shows an example of the casting machine which concerns on a prior art example, and has shown the mode at the time of a casting start. It is a perspective view of the ladle shown in FIG.

  The form for implementing this invention is demonstrated below.

[Embodiment 1]
1 is a cross-sectional view showing a configuration of a casting machine according to Embodiment 1. FIG. Specifically, FIG. 1 shows a state at the end of casting.

  FIG. 2 is an enlarged view of a ladle and a chute, which is a molten metal supply structure in the casting machine shown in FIG.

  A casting machine 100 shown in FIG. 1 includes an arc ladle (ladder) 3 to which a molten metal 2 is supplied from a stationary ladle 1, a motor 4, a chute 5, a trough 6, a casting part 7, and a trough moving part 8. Yes. The arc ladle 3 includes a ladle body 9 and a nozzle (a pouring gate) 10.

  The ladle body 9 stores the molten metal 2. The ladle body 9 has a first cross section (cross section in a direction parallel to the plane defined by the pouring direction from the ladle body to the outside and the vertical direction, that is, the same surface as the paper surface), the shape centering on the center 3c. The bottom surface part 9b which is a first arc is provided. In other words, the first cross-sectional view of the ladle body 9 has a fan shape centered on the center 3c. The ladle body 9 is rotated by a motor 4 within a plane defined by the pouring direction from the ladle body 9 to the outside and the vertical direction with the center 3c as a rotation axis. The bottom surface portion 9b is provided so as to extend along the rotation axis (in the front and back direction of the paper).

  The nozzle 10 is disposed on the bottom surface portion 9b. The arc ladle 3 is capable of pouring the molten metal 2 stored in the ladle body 9 from the nozzle 10 to the outside. By controlling the rotation angle of the ladle body 9 by the motor 4, it is possible to adjust the amount of the molten metal 2 poured from the ladle body 9 to the outside. Further, the nozzle 10 is also rotated following the rotation of the ladle body 9.

  The chute 5 is a groove-shaped member that receives the molten metal 2 poured from the arc ladle 3 and guides the received molten metal 2 in the horizontal direction. The chute 5 has a coating mold (graphite or the like) applied to its surface. The molten metal 2 guided by the chute 5 is supplied to the trough 6.

  In the first cross section, the chute 5 has an angle θ (see FIG. 2) formed by a pouring direction from the ladle body 9 to the outside and a direction in which the chute 5 guides the molten metal 2 is 90 ° or more and 270 ° or less. is there. Preferably, it is 180 degrees or less. Here, the direction in which the chute 5 guides the molten metal 2 is the flow direction of the molten metal 2 at the tip of the chute 5 (the direction in which the molten metal 2 is guided to the trough 6), and the angle θ is the ladle body as shown in FIG. This is an angle at which the flow direction changes from the direction of pouring from 9 to the outside and the direction in which the tip of the chute 5 leads the molten metal 2 to the trough 6. In other words, the direction in which the molten metal 2 flows at the tip of the chute 5 is substantially opposite to the direction of pouring from the nozzle 10 and the horizontal direction. Thereby, since the flow of the molten metal 2 poured from the arc ladle 3 can greatly change the flow direction by the chute 5, it is possible to buffer the momentum during pouring from the arc ladle 3. For this reason, the flow of the molten metal 2 supplied from the chute 5 can be stabilized. The chute 5 is a second arc in which the first cross-sectional shape is centered on the center 3c and the distance from the first arc to the center 3c is far. Thereby, it is easy to make the shortest distance d (refer FIG. 2) of the bottom face part 9b and the chute | shoot 5 constant. By making the shortest distance d constant, it is possible to further stabilize the chute 5 from guiding the molten metal 2.

  The trough 6 is a groove through which the molten metal 2 passes, extends slightly inclined so that the casting part 7 side is lowered, and is placed on the carriage 6b. The trough moving unit 8 is, for example, a rail, and moves the carriage 6b along the extending direction of the trough 6. The trough 6 usually has an inclination angle parallel to the rail, but it may be possible to further incline the casting part 7 side relative to the rail.

  The casting unit 7 includes a mold 11, a sleeve 12, a mold rotation mechanism 13, and a vibration damping table 14. The mold 11 and the sleeve 12 are cylindrical. The sleeve 12 is provided concentrically with the mold 11 so as to surround the mold 11. Further, a space 15 is formed between the mold 11 and the sleeve 12, and the mold 11 can be cooled by supplying a cooling fluid (water or the like) to the space 15. The molten metal 2 guided to the trough 6 flows down from the end of the trough 6 on the casting part 7 side (hereinafter referred to as the end of the trough 6) and is guided to the mold 11. That is, the end of the trough 6 is a supply part of the molten metal 2 to the mold 11.

  The mold rotation mechanism 13 rotates the mold 11 and the sleeve 12 about the cylindrical axis of the mold 11 as a rotation axis. As a rotation method by the mold rotation mechanism 13, both ends of the sleeve 12 are supported by support rollers, and a roller mounted on the vibration damping table 14 is brought into contact with the lower side of the sleeve 12 to be mounted on the vibration damping table 14. For example, a method of rotating a roller by a motor can be used.

  The damping table 14 suppresses vibration of the mold 11 when the mold 11 and the sleeve 12 are rotated. Further, as described above, the vibration damping table 14 is provided with a roller, and this roller rotates the mold 11 and the sleeve 12 (part of the function of the mold rotation mechanism 13).

  In the casting machine 100, the position of the nozzle 10 can be changed by rotating the ladle body 9. Thereby, the position where the chute 5 receives the molten metal 2 can be appropriately changed according to the rotation angle of the ladle body 9. As a result, even if the coating mold applied to the molten metal contact surface on the surface of the chute 5 is not thickly applied, it is possible to suppress the occurrence of seizure on the surface of the chute 5 and to reduce damage to the chute 5.

  Further, the width Z3 of the bottom surface portion 9b in the direction along the rotation axis is less than the diameter dca of the circle ca having the first arc (see FIGS. 2 and 9). FIG. 9 is a perspective view of the arc ladle 3. In other words, the width of the bottom surface portion 9 b is less than the maximum value of the width of the side surface portion that is a sector shape of the ladle body 9. Thereby, since it becomes possible to make small the change of the pouring amount accompanying rotation of the arc ladle 3 by making the width | variety of the ladle main body 9 in the direction perpendicular | vertical with respect to the pouring direction, The amount of pouring can be easily controlled.

  As shown in FIG. 2, the nozzle 10 has a substantially cylindrical shape. In the first cross section, the nozzle 10 is positioned on a line segment connecting the center 3 c (rotating shaft) and the center 10 c of the nozzle 10. The axial center 10ax is preferably arranged. Thereby, the flow of the molten metal 2 passing through the nozzle 10 can be made smooth.

[Embodiment 2]
3 and 4 are sectional views showing the configuration of the casting machine according to the second embodiment. Specifically, FIG. 3 shows a state at the start of casting, and FIG. 4 shows a state at the end of casting.

  The casting machine 140 shown in FIGS. 3 and 4 is different from the casting machine 100 shown in FIG.

  That is, in the casting machine 140, the chute 5 has an angle θ of 90 in the first cross section formed by the pouring direction from the ladle body 9 to the outside and the direction in which the tip of the chute 5 leads the molten metal 2 to the trough 6. Arranged to be less than °. In other words, the direction in which the molten metal 2 flows at the tip of the chute 5 is substantially the same in the horizontal direction and the direction of pouring from the nozzle 10. In the casting machine 140, the chute 5 has a circular arc in the first cross section, but the circular arc is not centered on the center 3c (not the second arc).

  The casting machine 100 can further stabilize the flow of the molten metal 2 than the casting machine 140, and can further stabilize the chute 5 from guiding the molten metal 2. However, also in the casting machine 140, the position where the chute 5 receives the molten metal 2 can be appropriately changed according to the rotation angle of the ladle body 9. Therefore, it is possible to stabilize the flow of the molten metal 2, suppress deterioration of the casting quality, and reduce damage to the chute 5.

[Manufacturing method of casting]
With reference to FIG. 3 and FIG. 4, the manufacturing method of the casting using the casting machine 140 is demonstrated below. The casting machine 100 can also be manufactured by a manufacturing method described below.

  When casting by the casting machine 140 is started, first, the molten metal 2 is poured from the arc ladle 3. The molten metal 2 poured from the arc ladle 3 is guided in the order of the chute 5 and the trough 6, and is supplied to the mold 11 from the end of the trough 6 (molten supply process).

  At this time, the mold 11 and the sleeve 12 are rotated about the cylindrical axis of the mold 11 by the mold rotation mechanism 13. Further, at this time, as shown in FIG. 3, the trough 6 is moved by the trough moving unit 8 so that the end of the trough 6 is moved in the direction of the chute 5. Thereby, the terminal end of the trough 6 moves toward the chute 5 side in the mold 11. Therefore, if the initial position of the trough 6 is set so that the molten metal 2 can be supplied to the end of the mold 11 opposite to the chute 5, the mold 11 can be connected to the end of the chute 5 from the end opposite to the chute 5. The molten metal 2 is sequentially supplied to the end portion.

  Further, at this time, the trough 6 may be further inclined so that the cast part 7 side is lowered with respect to the rail of the trough moving part 8. Thereby, the molten metal 2 remaining on the trough 6 without flowing through the trough 6 can be guided without leaving the mold 11 from the end of the trough 6. As a result, it is possible to increase the utilization efficiency of the molten metal 2 and to prevent surplus soot (jam) from remaining on the trough 6.

  When the casting by the casting machine 140 is finished, the end of the trough 6 is closer to the chute 5 than the mold 11 as shown in FIG. The molten metal 2 is supplied over the entire mold 11. In addition, it is preferable that the arc ladle 3 pours a required amount of the molten metal 2 for each casting.

[Solving problems related to ladle]
By using the arc ladle 3, the problems related to the triangular ladle 103 can be solved. This will be described with reference to FIG. FIG. 5 is a cross-sectional view of the arc ladle 3 and the chute 5 of the casting machine 140.

  The molten metal 2 stored in the ladle body 9 can be mixed with the paste 16. The plaque 16 is light enough to float on the molten metal 2. Therefore, by pouring while maintaining the nozzle 10 sufficiently below the liquid level of the molten metal 2, it is possible to prevent the scale 16 from flowing out together with the molten metal 2.

  In addition, the ladle body 9 is rotated so that the level of the liquid level of the molten metal 2 with respect to the nozzle 10 is kept constant during pouring, so that the pressure applied to the nozzle 10 is kept constant. Since the moment at which the molten metal 2 is poured can be kept constant, the amount of the molten metal 2 poured can be easily quantified to some extent strictly.

  With reference to FIG. 6, a description will be given of keeping the momentum at which the molten metal 2 is poured from the nozzle 10 constant. FIG. 6 is a diagram showing the height relationship between the nozzle 10 and the liquid level of the molten metal 2 in the arc ladle 3 in time series.

  FIG. 6A shows a state before the molten metal 2 is supplied from the stationary ladle 1. At this time, the nozzle 10 is at a position higher than the liquid level of the molten metal 2. For this reason, the molten metal 2 is not poured from the ladle body 9.

  FIG. 6B shows a state immediately after the molten metal 2 is supplied from the stationary ladle 1. At this time, the nozzle 10 is still at a position higher than the liquid level of the molten metal 2. For this reason, the molten metal 2 is not poured from the ladle body 9.

  (C) of FIG. 6 has shown the mode in the pouring of the molten metal 2 (first half). (D) of FIG. 6 has shown the mode in the pouring (middle board) of the molten metal 2. FIG. FIG. 6E shows a state during the pouring of the molten metal 2 (second half). At these times, the nozzle 10 is positioned below a certain height Hmm of the liquid level of the molten metal 2 by the rotation of the ladle body 9. Here, the constant height Hmm is set to 50 mm, for example. For this reason, the molten metal 2 is poured from the ladle body 9. Further, the rotation angle of the ladle body 9 is maintained so that the nozzle 10 is maintained Hmm below the liquid surface of the molten metal 2 during the molten metal 2 (first half) to the molten metal 2 (second half). Is controlled. For this reason, during the pouring of the molten metal 2, the momentum at which the molten metal 2 is poured from the nozzle 10 can be kept constant, so that the amount of the molten metal 2 poured can be quantified to some extent strictly.

[Specific example of ladle structure]
FIG. 7 is a cross-sectional view showing a specific example of the configuration of the arc ladle 3.

  As shown in FIG. 7, the arc ladle 3 is provided on the ladle wall 31 that constitutes the inner wall of the ladle body 9, the iron skin 32 that covers the ladle wall 31 and constitutes the outer wall of the ladle body 9, and the center 3 c. A rotation shaft 33 extending in the front and back direction of the paper surface and a nozzle 10 are provided.

  For example, the radius of the outer wall of the ladle body 9 shown in FIGS. 2 and 9 (corresponding to the radius of the circle ca) is 250 mm, and the width of the ladle body 9 (corresponding to the width of the bottom surface portion 9b in the direction along the rotation axis). Is 150 mm and the length of the nozzle 10 is 110 mm.

[Additional Notes]
In the casting machines 100 and 140, the nozzle 10 is provided as a pouring port, but the shape of the pouring port is not limited to the cylindrical nozzle 10, and may be a conical shape, a prismatic shape, or the like. Moreover, as a formation method of a pouring spout, you may form the pouring spout by notching the bottom face part 9b of the ladle main body 9, for example.

  The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope shown in the claims, and embodiments obtained by appropriately combining technical means disclosed in different embodiments. Is also included in the technical scope of the present invention.

  INDUSTRIAL APPLICATION This invention can be utilized for the molten metal supply structure provided with the ladle which pours molten metal outside, the casting machine provided with this molten metal supply structure, and the manufacturing method of the casting using this casting machine.

1 Stationary ladle 2 Molten metal 3 Arc ladle (Ladle)
3c Center of the first arc (rotating axis)
4 Motor 5 Chute 6 Trough 7 Casting part 8 Trough moving part 9 Ladle body 9b Bottom face part 10 Nozzle 10ax Nozzle shaft center 10c Nozzle center 11 Mold 12 Sleeve 13 Mold rotation mechanism 14 Damping table 15 Space 31 Ladle wall 32 Iron skin 33 Rotating shaft 100 Casting machine 140 Casting machine

Claims (7)

Ladle and
Receiving a molten metal poured from the ladle, and a chute having a groove for guiding the received molten metal horizontally,
The ladle above is
A ladle body for storing the molten metal;
It has a pouring port for pouring the molten metal stored in the ladle body to the outside,
The ladle body is
The direction in which the upper Symbol chute leads to molten metal, in a plane defined by the vertical direction, a rotation shaft for rotating the ladle body,
A bottom portion for storing the molten metal;
The bottom portion has a first circular arc cross section taken along with the plane parallel to the direction around the shaft above times, and may be the first arc is extended along the rotation axis Curved surface ,
The pouring gate is disposed on the bottom surface ,
The ladle body is configured such that the rotation angle is controlled during pouring of the molten metal so that the pouring spout is maintained below a certain level of the liquid level of the molten metal stored in the ladle body. Has been
The molten metal supply structure in which the position at which the chute receives the molten metal poured from the ladle main body to the outside changes according to the rotation angle of the ladle main body . In a cross section in the plane parallel to the direction, relative to the direction of pouring is carried out to the outside from the ladle body, as the angle of the direction in which the chute guides the molten metal becomes 90 ° or more than 180 °, collected the The molten metal supply structure according to claim 1, wherein the pan body is configured to allow pouring . The chute, the cross-sectional surface cut into the plane parallel to the direction, around the shaft above times and said the distance from the first arc to the rotation axis is distant second arc The molten metal supply structure according to claim 1 or 2.   The molten metal supply structure according to any one of claims 1 to 3, wherein a width of the bottom surface portion in a direction along the rotation axis is less than a diameter of a circle having the first arc. The pouring gate is composed of a substantially cylindrical nozzle,
In a cross section in the plane parallel to the direction, the molten metal supply structure according to claim 1, any one of 4 straight lines stretched axis of the upper Symbol nozzle is characterized in that through the shaft above times.   A casting machine comprising the molten metal supply structure according to any one of claims 1 to 5.   A method for producing a casting using a casting machine,
  The casting machine is
    Ladle and
    Receiving a molten metal poured from the ladle, and a chute having a groove for guiding the received molten metal horizontally,
    The ladle above is
      A ladle body for storing the molten metal;
      It has a pouring port for pouring the molten metal stored in the ladle body to the outside,
      The ladle body is
        A rotating shaft for rotating the ladle body in a plane defined by a direction in which the chute guides the molten metal and a vertical direction;
        A bottom portion for storing the molten metal;
        The bottom surface has a first arc whose cross section cut in a direction parallel to the plane has a first arc centered on the rotation axis, and is a curved surface formed by extending the first arc along the rotation axis And
      The pouring gate is disposed on the bottom surface,
  During pouring of the molten metal, the rotation angle of the ladle body is controlled so that the pouring spout is maintained below a certain level of the liquid level of the molten metal stored in the ladle body,
  A method for producing a casting, characterized in that a position at which the chute receives molten metal poured from the ladle body to the outside is changed according to a rotation angle of the ladle body.

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