JP2013063471A - Method of determining reference position of grooved rolling roll - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of determining the reference position of grooved rolling rolls, capable of easily determining the reference position for adjusting the pressing position of the groove rolling rolls arranged in a rolling stand, and capable of easily calibrating the pressing position.SOLUTION: In the rolling stand 200, there are arranged the two grooved rolling rolls R11, R12 which are adjustable in position in a direction X perpendicular to the pressing direction Y. The method of determining the reference position of the grooved rolling rolls includes moving the grooved rolling roll R11 provided with a third straight part L3 or the grooved rolling roll R12 provided with a fourth straight part L4 in the direction Y perpendicular to the pressing direction X until the third straight part L3 of the grooved rolling roll R11, which is provided with the third straight part L3, contacts with the fourth straight part L4 of the grooved rolling roll R12, which is provided with the fourth straight part L4, under a constant load.

Description

  The present invention relates to a method for determining a reference position of a perforated rolling roll provided in a rolling stand for rolling a tubular or bar-shaped material to be rolled such as a seamless pipe or a steel bar. In particular, according to the present invention, it is possible to easily determine a relative reference position for adjusting the reduction position of the perforated rolling roll disposed in the rolling stand and to easily calibrate the reduction position. The present invention relates to a reference position determination method.

  In the production of a seamless pipe by the Mannesmann-Mandrel mill method, first, a round billet or a square billet is heated in a heating furnace, and then a hollow shell is produced by piercing and rolling with a piercing machine. Next, a mandrel bar is inserted into the inner surface of the hollow shell and stretch-rolled by a mandrel mill comprising a plurality of rolling stands. Thereafter, the tube material is formed and rolled to a predetermined outer diameter with a drawing mill to obtain a product.

  Conventionally, as shown in FIG. 1 (a), two perforated rolling rolls R11 ′ and R12 ′ are arranged facing each rolling stand, and perforated rolling rolls R11 ′ and R12 ′ are arranged between adjacent rolling stands. 2 roll mandrel mills that are alternately arranged with the rolling direction of 90 ° shifted, and three perforated rollings such that the angle formed by the rolling direction on each rolling stand is 120 ° as shown in FIG. Rolls R21 ′, R22 ′, R23 ′ are disposed, and a three-roll mandrel mill in which the rolling direction of the roll-type rolling rolls R21 ′, R22 ′, R23 ′ is alternately shifted by 60 ° between adjacent rolling stands is provided. It is used. Furthermore, as shown in FIG. 1C, four perforated rolling rolls R31 ′, R32 ′, R33 ′, and R34 ′ are arranged on each rolling stand so that the angle formed in the rolling direction is 90 °. A 4-roll mandrel mill is also applied.

  Here, in order to ensure the thickness accuracy of the material to be rolled in the mandrel mill and further suppress uneven thickness, the rolling position of each hole-type rolling roll provided in each rolling stand of the mandrel mill (rolling the material to be rolled) It is important to set the position of each perforated rolling roll with respect to the material to be rolled to an appropriate position. Specifically, as shown in FIG. 1, it is important that the groove bottom B of each perforated rolling roll is at a position that is evenly spaced from the pass line center O of the material to be rolled by a desired amount. However, due to the effects of dimensional tolerances and installation errors of each hole rolling roll and the tool that holds the hole rolling roll, it is actually difficult to set the rolling position of each hole rolling roll as designed. is there.

  Therefore, in the two-roll type mandrel mill, the opposed perforated rolling rolls R11 ′ and R12 ′ are moved in the reduction direction (the direction of the arrow in FIG. 1A), and the flange portions F ′ are brought into contact with each other. A method is used in which the rolls are pressed against each other with a constant load, and the position of each of the perforated rolling rolls R11 ′ and R12 ′ at this time is used as a reference position in the reduction direction to adjust the reduction position in the reduction direction. Specifically, after determining the reference positions of the perforated rolling rolls R11 'and R12', the positions of the perforated rolling rolls R11 'and R12' are evenly moved from the reference position in the reduction direction.

  However, in the case of a three-roll type or four-roll type mandrel mill, the degree of freedom in the relative relationship between the positions of the respective hole rolling rolls is large. The direction reference position cannot be determined properly. Therefore, there is a problem that it is difficult to suppress uneven thickness of the material to be rolled because the reduction position of each perforated rolling roll cannot be adjusted to an appropriate position.

  In Patent Document 1, for a three-roll mandrel mill, a wall thickness measuring device is arranged on the mandrel mill outlet side, and each die rolling is performed based on the measured thickness value of the material to be rolled measured by the wall thickness measuring device. A method for adjusting the rolling position of the roll in the rolling direction has been proposed. However, for the material to be rolled first, since there is no measurement value by the thickness measuring device, at least for the first material to be rolled, the reduction position of each perforated rolling roll cannot be adjusted to an appropriate position, It is difficult to suppress uneven thickness.

  On the other hand, even in the case of a two-roll mandrel mill, as shown in FIG. 2, the perforated rolling roll R11 is affected by the dimensional tolerance of each perforated rolling roll and the tool that holds the perforated rolling roll, installation errors, and the like. In some cases, the position in the direction perpendicular to the rolling direction of ', R12' (the direction indicated by the arrow in FIG. 2) is shifted. If the positional deviation in the direction perpendicular to the rolling direction occurs, unevenness occurs in the material P to be rolled. However, this misalignment cannot be corrected by a method in which the above-described perforated rolling rolls R11 'and R12' are moved in the reduction direction and the flange portions are brought into contact with each other.

  Patent Document 2 proposes a method of individually adjusting the amount of confinement on each flange side of the perforated rolling roll provided in the mandrel mill based on the measured thickness of the material to be rolled measured downstream of the mandrel mill. ing. According to the method described in Patent Document 2, the reduction position of the perforated rolling roll can be adjusted in a direction perpendicular to the reduction direction by varying the amount of confinement on each side. However, since there is no measured thickness for the material to be rolled for the first time, at least for the first material to be rolled, the reduction position in the direction perpendicular to the reduction direction of each perforated rolling roll is set to an appropriate position. It cannot be adjusted and it is difficult to suppress the uneven thickness as shown in FIG. The same applies to a three-roll or four-roll mandrel mill.

  The problems of the prior art described above are not limited to mandrel mills, but are common to rolling stands that roll a material to be rolled using a perforated rolling roll.

JP 2005-131706 A JP 2003-220403 A

  The present invention was created in order to solve such a problem of the prior art, and is a hole-type rolling roll provided in a rolling stand for rolling a tubular or rod-shaped material to be rolled such as a seamless tube or a steel bar. A method for determining a reference position, in which a reference position for adjusting a reduction position of a rolling mill roll arranged in the rolling stand can be easily determined, and the rolling roll can be easily calibrated. It is an object of the present invention to provide a reference position determination method.

A first means of the present invention is a method for determining a reference position of a perforated rolling roll in a rolling stand provided with two perforated rolling rolls, and a direction perpendicular to the reduction direction and the reduction direction of the perforated rolling roll. It is an object of the present invention to provide a method for determining the reference position of a perforated rolling roll, which can easily determine the reference position, and can easily calibrate the reduction position.
That is, the first means of the present invention is a reference position determination method for adjusting the rolling position of a perforated rolling roll provided in a rolling stand provided with a plurality of perforated rolling rolls. The two perforated rolling rolls whose positions can be adjusted in the direction perpendicular to the rolling direction are arranged at opposing positions, and each perforated rolling roll includes a center line of the rotation axis of the perforated rolling roll and is rolled. Regarding the cross-sectional shape of each of the perforated rolling rolls cut by a plane perpendicular to the pass line of the material, the cross-sectional shape of one perforated rolling roll is at least a third straight portion extending parallel to the rolling direction at least one flange portion And the cross-sectional shape of the other perforated rolling roll is provided with a fourth straight part facing the third straight part and extending in parallel with the third straight part in the flange part, and the third straight line Part of a perforated rolling roll having a section Until the straight line portion comes into contact with the fourth straight line portion of the perforated rolling roll including the fourth straight line portion under a constant load, the perforated rolling roll including the third straight line portion or the fourth straight line portion Provided is a method for determining a reference position of a hole-type rolling roll, characterized in that the hole-type rolling roll provided is moved in a direction perpendicular to the reduction direction.

A second means of the present invention is a method for determining a reference position of a perforated rolling roll in a rolling stand provided with four perforated rolling rolls, and a direction perpendicular to the reduction direction and the reduction direction of the perforated rolling roll. It is an object of the present invention to provide a method for determining the reference position of a perforated rolling roll, which can easily determine the reference position, and can easily calibrate the reduction position.
That is, the second means of the present invention is a reference position determination method for adjusting the rolling position of a perforated rolling roll provided in a rolling stand provided with a plurality of perforated rolling rolls. The four perforated rolling rolls are arranged so that the angles formed by the respective rolling directions are 90 °, and each perforated rolling roll includes the center line of the rotation axis of the perforated rolling roll, and the material to be rolled As for the cross-sectional shape of each of the perforated rolling rolls formed by cutting along a plane perpendicular to the pass line, the cross-sectional shape of any one set of perforated rolling rolls is such that the first straight portion extending perpendicularly to the rolling direction is on both sides. And the flange portion on both sides includes a third linear portion extending in parallel with the rolling direction, and the cross-sectional shape of another set of perforated rolling rolls is opposed to the first linear portion, A second straight line extending in parallel with the first straight line portion In the flange portion, and the flange portion includes a fourth straight portion that faces the third straight portion and extends in parallel with the third straight portion, and the second straight portion and the fourth straight portion. Opening the other set of perforated rolling rolls comprising: the first straight portion and the second straight portion so as to keep the first straight portion and the second straight portion facing each other; The first linear portion of the set of perforated rolling rolls including the third linear portion is the second of the other pair of perforated rolling rolls including the second linear portion and the fourth linear portion. Closing the pair of perforated rolling rolls including the first straight portion and the third straight portion in a rolling direction until they contact the straight portion under a constant load; and the first straight portion and the first straight portion The set of perforated rolling rolls having three straight portions is divided into the third straight portion and the first A step of evenly opening in the rolling direction so as to keep the four linear portions facing each other, and a fourth of the other pair of perforated rolling rolls comprising the second linear portion and the fourth linear portion. The second linear portion and the fourth linear portion until the linear portion contacts the third linear portion of the pair of perforated rolling rolls including the first linear portion and the third linear portion under a certain load. There is provided a method for determining a reference position of a hole rolling roll, characterized by sequentially performing the step of closing the other set of hole rolling rolls each having a straight portion in a rolling direction.

  According to the present invention, since it is possible to easily determine the reference position for adjusting the rolling position of the perforated rolling roll disposed on the rolling stand, the rolling position of each perforated rolling roll can be adjusted to an appropriate position, for example, When the material to be rolled is tubular, the uneven thickness can be suppressed.

FIG. 1 is a longitudinal sectional view schematically showing an example of a rolling stand constituting a mandrel mill. FIG. 2 is a vertical cross-sectional view for explaining a positional deviation in the horizontal direction of the perforated rolling roll constituting the rolling stand. FIG. 3 is a longitudinal sectional view showing a schematic configuration of a rolling stand constituting the three-roll mandrel mill according to the first embodiment of the present invention and an example of a procedure for determining a reference position for adjusting the rolling position. FIG. 4 is a longitudinal sectional view showing a schematic configuration of a rolling stand that constitutes a three-roll mandrel mill according to a modification of the first embodiment of the present invention. FIG. 5: is a longitudinal cross-sectional view which shows an example of the determination procedure of the reference position for schematic structure of a rolling stand which comprises the 3 roll type mandrel mill which concerns on 2nd Embodiment of this invention, and a rolling position adjustment. FIG. 6 is a longitudinal sectional view showing a schematic configuration of a rolling stand constituting the two-roll mandrel mill according to the third embodiment of the present invention. FIG. 7: is a longitudinal cross-sectional view which shows an example of the schematic structure of the rolling stand which comprises the 4 roll type mandrel mill which concerns on 4th Embodiment of this invention, and the determination procedure of the reference position for rolling position adjustment.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings as appropriate.
<First Embodiment>
FIG. 3 is a longitudinal sectional view showing a schematic configuration of a rolling stand constituting the three-roll mandrel mill according to the first embodiment of the present invention and an example of a procedure for determining a reference position for adjusting the rolling position. As shown in FIG. 1, a rolling stand 100 according to the present embodiment is provided with a housing (not shown) and an angle formed by the rolling direction of each perforated rolling roll at 120 ° in the housing. Three perforated rolling rolls R21, R22, R23 are provided.

  Longitudinal cross-sectional shapes of the perforated rolling rolls R21, R22, R23 provided in the rolling stand 100 according to the present embodiment (pass line of the material to be rolled (reference numeral O in FIG. 3G indicates the center of the pass line of the material to be rolled) (Cross-sectional shape orthogonal to the above) has the following characteristics. In other words, any one of the perforated rolling rolls R21 includes first linear portions L1 extending perpendicularly to the rolling direction (the Y direction in FIG. 3A) on both flange portions. Further, the other two perforated rolling rolls R22 and R23 are provided with a second straight portion L2 facing the first straight portion L1 and extending in parallel to the first straight portion L1, in the flange portion.

  In the rolling stand 100 having the above-described configuration, the determination of the reference position in the Y direction for adjusting the reduction positions of the perforated rolling rolls R21, R22, R23 is performed, for example, by the following procedure.

  First, as shown in FIG. 3 (b) among the hole rolling rolls R21 to R23 in the initial state (the state shown in FIG. 3 (a)), the hole rolling roll R22 provided with the second straight portion L2. , R23 are opened in the down direction (moved away from the pass line center O). Next, as shown in FIG. 3C, the perforated rolling roll R21 is closed in the reduction direction (moved so as to approach the pass line center O). By the above operation, when the linear part L1 and the linear part L2 are brought into contact as will be described later, it is possible to prevent the flange part F22 of the perforated rolling roll R22 and the flange part F23 of the perforated rolling roll R23 from contacting each other. It is.

  Next, as shown in FIG. 3 (d), until the second straight part L2 of the perforated rolling rolls R22 and R23 comes into contact with the first straight part L1 of the perforated rolling roll R21 under a certain load, The rolling rolls R22 and R23 are each closed in the reduction direction. At this time, since the flange portion F22 on the side where the linear portion L2 of the hole rolling roll R22 is not provided and the flange portion F23 on the side where the linear portion L2 of the hole rolling roll R23 is not provided do not contact, Contact between the first straight line portion L1 and the second straight line portion L2 is not hindered.

  Next, as shown in FIG. 3 (e), after opening the perforated rolling roll R21 having the first straight portion L1 in the rolling-down direction, the second straight portion L2 is moved as shown in FIG. 3 (f). The perforated rolling rolls R22 and R23 provided are each uniformly closed in the reduction direction until the flange portions F22 and F23 come into contact with each other under a certain load.

  Finally, as shown in FIG. 3 (g), until the first straight line portion L1 of the perforated rolling roll R21 comes into contact with the second straight line portion L2 of the perforated rolling rolls R22 and R23 under a certain load. The rolling roll R21 is closed in the reduction direction.

  By the procedure described above, at least the reference position in the Y direction of the perforated rolling rolls R21 to R23 can be determined. And each piercing-rolling roll R21-R23 can calibrate a reduction position based on the information of the reference position (position shown in Drawing 3 (g)), and can suppress uneven thickness of a material to be rolled. is there. If the hole rolling rolls R21 to R23 are moved integrally by moving the housing so that the center of gravity of each hole rolling roll R21 to R23 at the reference position matches the pass line center O, It is possible to calibrate the reduction position with reference to the pass line center O.

  In addition, in the rolling stand according to the present embodiment described above, in order to easily determine the reference position in the direction perpendicular to the rolling direction as well as the rolling direction of the perforated rolling roll, as shown in FIG. A rolling stand 100A is preferable. Hereinafter, a difference between the rolling stand 100A shown in FIG. 4 and the rolling stand 100 described above will be mainly described.

  FIG. 4 is a longitudinal sectional view showing a schematic configuration of a rolling stand that constitutes a three-roll mandrel mill according to a modification of the first embodiment of the present invention. As shown in FIG. 4, the longitudinal cross-sectional shape of the perforated rolling rolls R <b> 21 </ b> A, R <b> 22 </ b> A, and R <b> 23 </ b> A provided in the rolling stand 100 </ b> A according to this embodiment is as follows. It has the characteristics of. That is, any one of the perforated rolling rolls R21A further includes a third straight line portion L3 extending in parallel to the rolling direction (Y direction in FIG. 4) on at least one flange (on both sides in the example shown in FIG. 4). To do. In addition, at least one of the other two rolls R22A and R23A (both in the example shown in FIG. 4) faces the third straight part L3 and is parallel to the third straight part L3. The flange portion further includes a fourth straight portion L4 that extends. It is to be noted that the hole rolling roll R21A is the same as the hole rolling roll R21 described above in that the first straight portions L1 extending perpendicularly to the rolling direction are provided in the flange portions on both sides. Further, the point that the hole rolling rolls R22A and R23A are provided with the second straight line portion L2 facing the first straight line portion L1 and extending in parallel to the first straight line portion L1 in the flange portion is described above. , R23.

  In the rolling stand 100A having the above-described configuration, the determination of the reference position in the Y direction for adjusting the reduction position of the perforated rolling rolls R21A, R22A, R23A is the same as that of the rolling stand 100 described above with reference to FIG. Made in the procedure.

  On the other hand, the determination of the reference position in the direction perpendicular to the rolling direction (X direction in FIG. 4) is performed, for example, after determining the reference position in the Y direction, from the state shown in FIG. This is done by moving the hole rolling roll R21A in the X direction until the part L3 contacts the fourth linear portion L4 of the hole rolling roll R22A or R23A under a certain load. In the modification shown in FIG. 4, since the third straight portions L3 are provided on the flange portions on both sides of the perforated rolling roll R21A, any one of the third straight portions L3 is opposed to the fourth straight portion L4. Alternatively, the interval between the third linear portions L3 and the interval between the fourth linear portions L4 may be substantially equal, and the third linear portion L3 may be fitted between the fourth linear portions L4. It is also possible to determine the reference position in the X direction of the perforated rolling roll R21A. The determination of the reference position in the X direction of the perforated rolling roll R21A can be realized by attaching a drive mechanism (cylinder device or the like) that advances and retreats in the X direction to the perforated rolling roll. Similarly to the technology, it can be realized by attaching a drive mechanism that advances and retracts in the Y direction on both sides of the rotary roll roll in the rotation axis direction, and by making the advance and retreat amounts of both drive mechanisms different (in the latter case, the roll roll) Can move in the X direction at the same time as the Y direction, but it is also possible to move only in the X direction by reversing the directions of the forward and backward movements of the two drive mechanisms and making the absolute values the same).

  By the procedure described above, according to the rolling stand 100A according to the present modification, not only the Y direction of the perforated rolling rolls R21A to R23A but also the reference position in the X direction can be determined. Each of the perforated rolling rolls R21A to R23A can calibrate the reduction position based on the information on the reference position, and can further suppress uneven thickness of the material to be rolled.

Second Embodiment
FIG. 5: is a longitudinal cross-sectional view which shows an example of the determination procedure of the reference position for schematic structure of a rolling stand which comprises the 3 roll type mandrel mill which concerns on 2nd Embodiment of this invention, and a rolling position adjustment. As shown in FIG. 5, a rolling stand 100B according to the present embodiment is arranged such that a housing (not shown) and an angle formed by the rolling direction of each perforated rolling roll are 120 ° in the housing. Three perforated rolling rolls R21B, R22B, R23B are provided.

  Vertical sectional shape of the perforated rolling rolls R21B, R22B, R23B provided in the rolling stand 100B according to the present embodiment (pass line of the material to be rolled (the symbol O in FIG. 5 (h) indicates the center of the pass line of the material to be rolled)) Unlike the first embodiment, the cross-sectional shape orthogonal to (2) does not need to have a feature, and can have the same shape as the conventional one (see FIG. 1B). However, in the rolling stand 100B according to the present embodiment, at least any two (three in the present embodiment) of the perforated rolling rolls R21B, R22B, R23B are on both sides of the three perforated rolling rolls R21B, R22B, R23B. It is possible to close further in the reduction direction (moves so as to approach the pass line center O of the material to be rolled) than a position where the flange portions of the two come into contact with each other (position shown in FIG. 5 (h)). It has the characteristics. In this configuration, for example, the stroke of a drive mechanism (cylinder device or the like) that is attached to each of the perforated rolling rolls R21B, R22B, and R23B and advances and retracts each perforated rolling roll R21B, R22B, and R23B in the reduction direction is shown in FIG. It is realizable by extending in the direction which approaches the pass line center O of a to-be-rolled material rather than the state shown to h).

  In the rolling stand 100B having the above-described configuration, the determination of the reference position in the rolling direction of each rolling mill roll for adjusting the rolling position of the rolling mill rolls R21B, R22B, and R23B is performed in the following procedure, for example.

  In order to determine the reference position in the rolling direction of the perforated rolling roll R21B, first, among the perforated rolling rolls R21B to R23B in the initial state (the state shown in FIG. 5A), FIG. As shown, the perforated rolling rolls R21B and R22B are each opened in the reduction direction (moved away from the pass line center O). At this time, when the perforated rolling roll R23B is closed in the rolling-down direction as described later (when the state shown in FIG. 5 (c) is reached), the flange portion of the perforated rolling roll R23B is the same as that of the perforated rolling roll R21B. The perforated rolling roll R21B is opened until the position does not come into contact with the flange portion. Further, as described later, when the perforated rolling roll R23B is closed in the reduction direction (when the perforated rolling roll R23B is in the state shown in FIG. 5C), the position where the perforated rolling roll R23B does not interfere with the perforated rolling roll R22B; Until it becomes, the perforated rolling roll R22B is opened.

  Next, as shown in FIG. 5 (c), after the perforated rolling roll R23B is further closed in the rolling direction than the position shown in FIG. 5 (h) (after being moved closer to the pass line center O). Until the flange portion of the hole rolling roll R21B comes into contact with the side surface of the hole rolling roll R23B under a certain load, the hole rolling roll R21B is closed in the reduction direction. At this time, since the side surface of the hole rolling roll R23B extends in parallel with the rolling direction of the hole rolling roll R23B, the flange portion of the hole rolling roll R21B is in contact with the side surface of the hole rolling roll R23B (hole shape). The rolling direction of the rolling roll R21B (the position in the Y1 direction in FIG. 5C) is constant regardless of the closing amount of the hole rolling roll R23B (the amount of movement from the position shown in FIG. 5H). Therefore, the reference position in the rolling direction of the punch roll R21B can be determined by the above procedure.

  Next, in order to determine the reference position in the rolling direction of the hole rolling roll R22B, among the hole rolling rolls R21B to R23B in the initial state (the state shown in FIG. 5A), it is shown in FIG. Thus, each of the perforated rolling rolls R22B and R23B is opened in the reduction direction (moved in a direction away from the pass line center O). At this time, as described later, when the perforated rolling roll R21B is closed in the reduction direction (when the state shown in FIG. 5 (e) is reached), the flange portion of the perforated rolling roll R21B is the same as that of the perforated rolling roll R22B. The perforated rolling roll R22B is opened until the position does not come into contact with the flange portion. Further, as described later, when the hole rolling roll R21B is closed in the reduction direction (when the state shown in FIG. 5 (e) is reached), the position where the hole rolling roll R21B does not interfere with the hole rolling roll R23B; Until it becomes, the perforated rolling roll R23B is opened.

  Next, as shown in FIG. 5 (e), after the perforated rolling roll R21B is further closed in the reduction direction than the position shown in FIG. 5 (h) (after being moved closer to the pass line center O). Until the flange portion of the hole rolling roll R22B comes into contact with the side surface of the hole rolling roll R21B under a certain load, the hole rolling roll R22B is closed in the reduction direction. At this time, since the side surface of the perforated rolling roll R21B extends in parallel to the rolling direction of the perforated rolling roll R21B, the flange portion of the perforated rolling roll R22B is in contact with the side surface of the perforated rolling roll R21B (the perforated mold). The rolling direction of the rolling roll R22B (the position in the Y2 direction in FIG. 5 (e)) is constant regardless of the closing amount of the perforated rolling roll R21B (the amount of movement from the position shown in FIG. 5 (h)). Therefore, the reference position in the rolling direction of the hole-type rolling roll R22B can be determined by the above procedure.

  Finally, in order to determine the reference position in the rolling direction of the hole rolling roll R23B, among the hole rolling rolls R21B to R23B in the initial state (the state shown in FIG. 5A), as shown in FIG. Thus, each of the perforated rolling rolls R21B and R23B is opened in the reduction direction (moved away from the pass line center O). At this time, when the perforated rolling roll R22B is closed in the rolling-down direction as described later (when the state shown in FIG. 5 (g) is reached), the flange portion of the perforated rolling roll R22B is the same as that of the perforated rolling roll R23B. The perforated rolling roll R23B is opened until the position does not come into contact with the flange portion. As will be described later, when the hole rolling roll R22B is closed in the reduction direction (when the state shown in FIG. 5 (g) is reached), the position where the hole rolling roll R22B does not interfere with the hole rolling roll R21B; Until then, the perforated rolling roll R21B is opened.

  Next, as shown in FIG. 5 (g), after the perforated rolling roll R22B is further closed in the reduction direction than the position shown in FIG. 5 (h) (after being moved closer to the pass line center O). Until the flange portion of the hole rolling roll R23B comes into contact with the side surface of the hole rolling roll R22B under a certain load, the hole rolling roll R23B is closed in the reduction direction. At this time, since the side surface of the perforated rolling roll R22B extends in parallel to the rolling direction of the perforated rolling roll R22B, the position where the flange portion of the perforated rolling roll R23B contacts the side surface of the perforated rolling roll R22B (the perforated mold). The rolling direction of the rolling roll R23B (the position in the Y3 direction in FIG. 5G) is constant regardless of the closing amount of the hole rolling roll R22B (the amount of movement from the position shown in FIG. 5H). Therefore, the reference position in the rolling direction of the perforated rolling roll R23B can be determined by the above procedure.

  By the procedure described above, it is possible to determine at least the reference position of the rolling mill rolls R21B to R23B in the rolling direction. And each piercing-rolling roll R21B-R23B can calibrate a reduction position based on the information of the reference position, and can suppress uneven thickness of a material to be rolled. If the hole rolling rolls R21B to R23B are integrally moved by moving the housing so that the center of gravity of each hole rolling roll R21B to R23B at the reference position matches the pass line center O, It is possible to calibrate the reduction position with reference to the pass line center O.

  In this embodiment, all of the three perforated rolling rolls R21B, R22B, and R23B can be closed in the rolling direction further than the position shown in FIG. 5 (h), and the perforated rolling roll R23B is illustrated. The reference position of the rolling roll R21B in the rolling direction is determined by closing it further in the rolling direction than the position shown in FIG. 5 (h), and the rolling roll R21B is pushed in the rolling direction further than the position shown in FIG. 5 (h). Is closed to determine the reference position of the rolling roll R22B in the rolling direction, and the rolling roll R22B is further closed in the rolling direction than the position shown in FIG. An example in which the reference position is determined has been described. However, the present invention is not limited to this, and it is only necessary that at least any two perforated rolling rolls can be closed in the rolling direction further than the position shown in FIG. For example, if the two perforated rolling rolls R22B and R23B can be further closed in the rolling direction than the position shown in FIG. 5 (h), the perforated rolling roll R23B is more than the position shown in FIG. 5 (h). Further, it is closed in the rolling direction, and the reference position of the rolling roll R21B in the rolling direction is determined by bringing the flange portion of the rolling roll R21B into contact with one side surface of the rolling roll R23B, and the rolling roll R22B. The reference position in the rolling direction of the hole rolling roll R22B can be determined by bringing the flange portion of the hole into contact with the other side surface of the hole rolling roll R23B. Then, the perforated rolling roll R22B is further closed in the reduction direction than the position shown in FIG. 5 (h), and the flange portion of the perforated rolling roll R23B is brought into contact with the side surface of the perforated rolling roll R22B in the same manner as described above. The reference position in the rolling direction of the perforated rolling roll R23B can be determined. Thus, if at least any two perforated rolling rolls can be further closed in the rolling direction than the position shown in FIG. 5 (h), for all three perforated rolling rolls R21B to R23B, The reference position in the rolling direction can be determined.

<Third Embodiment>
FIG. 6 is a longitudinal sectional view showing a schematic configuration of a rolling stand constituting the two-roll mandrel mill according to the third embodiment of the present invention. As shown in FIG. 6, the rolling stand 200 according to the present embodiment includes a housing (not shown) and two opposed perforated rolling rolls R11 and R12 arranged in the housing.

  Vertical cross-sectional shape of the perforated rolling rolls R11 and R12 provided in the rolling stand 200 according to the present embodiment (cross-sectional shape orthogonal to the pass line of the material to be rolled (the symbol O in FIG. 6 indicates the center of the pass line of the material to be rolled) ) Has the following characteristics. That is, one of the perforated rolling rolls R11 includes a third straight portion L3 extending in parallel to the rolling direction (Y direction in FIG. 6) at least on one side (both sides in the present embodiment). Further, the other hole-type rolling roll R12 includes a fourth linear portion L4 facing the third linear portion L3 and extending in parallel with the third linear portion L3 in the flange portion.

  In the rolling stand 200 having the above-described configuration, the determination of the reference position for adjusting the reduction positions of the perforated rolling rolls R11 and R12 is performed, for example, in the following procedure.

  As in the prior art, the Y-direction reference position is determined by closing the perforated rolling rolls R11 and R12 in the reduction direction (moving them closer to the pass line center O) and keeping the flange portions under a certain load. It is performed by contacting with.

  On the other hand, the determination of the reference position in the direction perpendicular to the rolling direction (the X direction in FIG. 6) is that the third straight line portion L3 of the hole rolling roll R11 is under a certain load on the fourth straight line portion L4 of the hole rolling roll R12. Is performed by moving the perforated rolling roll R11 or R12 in the X direction until contact is made. In this embodiment, since the 3rd linear part L3 is provided in the flange part of the both sides of the hole-type rolling roll R11, either one 3rd linear part L3 is made to contact the 4th linear part L4 which opposes this. Alternatively, the interval between the third straight line portions L3 and the distance between the fourth straight line portions L4 may be substantially equal, and the third straight line portion L3 may be fitted between the fourth straight line portions L4. It is also possible to determine the reference position in the X direction of the rolling roll R11 or R12. The determination of the reference position in the X direction of the hole rolling roll R11 or R12 can be realized by attaching a drive mechanism (cylinder device or the like) that moves back and forth in the X direction to the hole rolling roll. Similarly to the described technology, it is also possible to attach drive mechanisms that advance and retreat in the Y direction on both sides of the rotary axis direction of the perforated rolling roll, and to change the advance and retreat amounts of both drive mechanisms (however, in the latter case, The perforated rolling roll moves in the X direction simultaneously with the Y direction).

  The reference positions in the X direction and Y direction of the perforated rolling rolls R11 and R12 can be determined by the procedure described above. And each piercing-rolling roll R11, R12 can calibrate a reduction position based on the information of the reference position, and can suppress uneven thickness of a material to be rolled. If the hole rolling rolls R11 and R12 are moved integrally by moving the housing so that the center of gravity of the hole rolling rolls R11 and R12 at the reference position and the pass line center O coincide with each other, It is possible to calibrate the reduction position with reference to the pass line center O.

<Fourth embodiment>
FIG. 7: is a longitudinal cross-sectional view which shows an example of the schematic structure of the rolling stand which comprises the 4 roll type mandrel mill which concerns on 4th Embodiment of this invention, and the determination procedure of the reference position for rolling position adjustment. As shown in FIG. 7, the rolling stand 300 according to the present embodiment is arranged such that a housing (not shown) and the angle formed by the rolling direction of each perforated rolling roll is 90 ° in the housing. Four perforated rolling rolls R31, R32, R33, R34 are provided.

  The longitudinal cross-sectional shape of the perforated rolling rolls R31, R32, R33, R34 provided in the rolling stand 300 according to the present embodiment (the pass line of the material to be rolled (reference symbol O in FIGS. 7C and 7E is the material to be rolled). The cross-sectional shape perpendicular to the center of the pass line) has the following characteristics. That is, at least one (both in the present embodiment) of the pair of opposed roll rolls R31, R33 is perpendicular to the rolling direction (Y direction in FIG. 7A). One straight line portion L1 is provided on both flange portions, and a third straight line portion L3 extending in parallel to the rolling direction is provided on both flange portions. In addition, another set of perforated rolling rolls R32 and R34 includes a second straight line portion L2 facing the first straight line portion L1 and extending in parallel to the first straight line portion L1, and a third straight line. The flange portion includes a fourth linear portion L4 that faces the portion L3 and extends parallel to the third linear portion L3.

  In the rolling stand 300 having the above-described configuration, the determination of the reference position for adjusting the rolling position of the perforated rolling rolls R31, R32, R33, and R34 is performed, for example, by the following procedure.

  First, among the perforated rolling rolls R31 to R34 in the initial state (the state shown in FIG. 7A), as shown in FIG. 7B, the second straight portion L2 and the fourth straight portion L4 are provided. Opening rolling rolls R32 and R34 to be opened are each moved in the reduction direction (moved away from the center of the pass line). At this time, the perforated rolling rolls R32 and R34 are opened so as to keep the first straight line portion L1 and the second straight line portion L2 facing each other (the state having overlapping portions when viewed in the Y direction). Next, as shown in FIG. 7 (c), until the first linear portion L1 of the perforated rolling rolls R31 and R33 comes into contact with the second linear portion L2 of the perforated rolling rolls R32 and R34 under a certain load. The perforated rolling rolls R31 and R33 are each closed in the reduction direction (moved so as to approach the center of the pass line). At this time, as described above, since the perforated rolling rolls R32 and R34 are opened in the rolling direction in advance, the other portions of the flange portions of the perforated rolling rolls R31 to R34 are not in contact with each other. The contact between the first straight line portion L1 and the second straight line portion L2 is not inhibited.

  The reference position in the Y direction of the perforated rolling rolls R31 to R34 can be determined by the procedure described above.

  Next, as shown in FIG. 7 (d), the perforated rolling rolls R31 and R33 provided with the first straight line portion L1 and the third straight line portion L3 are equally opened in the reduction direction (in a direction away from the pass line center O). To move). At this time, the perforated rolling rolls R31 and R33 are opened so as to keep the third linear portion L3 and the fourth linear portion L4 facing each other (the state having overlapping portions when viewed in the X direction). Next, as shown in FIG. 7 (e), until the fourth linear portion L4 of the perforated rolling rolls R32, R34 comes into contact with the third linear portion L3 of the perforated rolling rolls R31, R33 under a constant load, The perforated rolling rolls R32 and R34 are closed in the reduction direction (moved so as to approach the pass line center O). At this time, as described above, since the perforated rolling rolls R31 and R33 are opened in the rolling direction in advance, the other portions of the flange portions of the perforated rolling rolls R31 to R34 are not in contact with each other. The contact between the three straight line portions L3 and the fourth straight line portion L4 is not inhibited.

  According to the procedure described above, in addition to the determination of the Y-direction reference position of the above-described perforated rolling rolls R31 to R34, the X-direction reference position can be determined. Each of the perforated rolling rolls R31 to R34 can calibrate the reduction position based on the information on the reference position, and can suppress uneven thickness of the material to be rolled. In addition, by moving the housing so that the center of gravity of each of the perforated rolling rolls R31 to R34 and the pass line center O at the positions moved uniformly from the reference positions in the X direction and the Y direction coincide with each other. If the perforated rolling rolls R31 to R34 are moved integrally, the reduction position can be calibrated with the pass line center O as a reference.

100, 100A, 100B, 200, 300 ... rolling stand L1 ... 1st straight line portion L2 ... 2nd straight line portion L3 ... 3rd straight line portion L4 ... 4th straight line portion R11, R12 .. Hole type rolling rolls R21, R21A, R21B, R22, R22A, R22B, R23, R23A, R23B ... Hole type rolling rolls R31, R32, R33, R34 ... Hole type rolling rolls

Claims (2)

A reference position determination method for adjusting the rolling position of a perforated rolling roll provided in a rolling stand provided with a plurality of perforated rolling rolls,
In the rolling stand, two perforated rolling rolls whose positions can be adjusted in a direction perpendicular to the rolling direction are arranged at opposing positions.
Regarding the cross-sectional shape of each perforated rolling roll formed by cutting each perforated rolling roll along a plane perpendicular to the pass line of the material to be rolled including the center line of the rotation axis of the perforated rolling roll,
The cross-sectional shape of one of the perforated rolling rolls includes a third straight portion extending in parallel with the rolling direction at least on one flange portion,
The cross-sectional shape of the other perforated rolling roll is provided with a fourth straight part facing the third straight part and extending in parallel with the third straight part in the flange part,
The third straight line until the third straight line portion of the perforated rolling roll including the third straight line portion contacts the fourth straight line portion of the perforated rolling roll including the fourth straight line portion under a certain load. A method for determining a reference position of a roll-type rolling roll, comprising: moving a roll-type rolling roll provided with a section or a roll-type rolling roll provided with the fourth straight part in a direction perpendicular to the rolling direction. A reference position determination method for adjusting the rolling position of a perforated rolling roll provided in a rolling stand provided with a plurality of perforated rolling rolls,
In the rolling stand, four perforated rolling rolls are arranged so that an angle formed by each rolling direction is 90 °,
Regarding the cross-sectional shape of each perforated rolling roll formed by cutting each perforated rolling roll along a plane perpendicular to the pass line of the material to be rolled including the center line of the rotation axis of the perforated rolling roll,
The cross-sectional shape of any one set of opposed roll rolls includes a first straight portion extending perpendicularly to the reduction direction in both flange portions, and a third straight portion extending parallel to the reduction direction to flanges on both sides. In the department,
The cross-sectional shape of another set of perforated rolling rolls includes a second straight part facing the first straight part and extending in parallel to the first straight part in the flange part, and the third straight part has The flange portion has a fourth straight portion facing and extending parallel to the third straight portion,
The other set of perforated rolling rolls having the second straight portion and the fourth straight portion is in a rolling direction so that the first straight portion and the second straight portion are kept facing each other. Step to open,
The first linear portion of the set of hole-type rolling rolls having the first linear portion and the third linear portion is the other set of holes having the second linear portion and the fourth linear portion. Closing the pair of perforated rolling rolls comprising the first straight part and the third straight part in a rolling direction until they contact the second straight part of the die rolling roll under a constant load;
The pair of perforated rolling rolls having the first straight portion and the third straight portion are equally distributed in the rolling direction so that the third straight portion and the fourth straight portion are kept facing each other. Step to open,
The set of holes in which the fourth linear portion of the other set of perforated rolling rolls including the second linear portion and the fourth linear portion includes the first linear portion and the third linear portion. Closing the other set of perforated rolling rolls comprising the second straight portion and the fourth straight portion in a rolling direction until they contact the third straight portion of the die rolling roll under a constant load;
Are sequentially executed. A method for determining a reference position of a perforated rolling roll.

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