JP3419699B2 - Mandrel and rolling equipment for furnace coiler - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mandrel for a furnace coiler used in, for example, a Steckel mill and a rolling mill equipped with the furnace coiler.

[0002]

2. Description of the Related Art A steckel mill is equipped with furnace coilers on the inlet side and outlet side of a hot rolling mill, respectively, and performs reversible rolling of several passes by a hot rolling mill while winding rolled material alternately on the furnace coiler. is there.

As this furnace coiler, conventionally, for example, as described in US Pat. No. 5,009,092, a housing, a mandrel for winding and unwinding rolled material, and a housing are provided in the housing. It has been proposed to have a heating means (for example, a burner) that prevents the temperature of the rolled material coil from decreasing during winding and unwinding.

At this time, the mandrel has a hollow and substantially cylindrical shape, and an axial opening is provided at one position in the circumferential direction. Guide portions for smoothly guiding the rolled material introduced into the furnace coiler into the substantially cylindrical shape are provided on both sides of the opening in the circumferential direction. The uniform thickness cylindrical portion other than the opening and the guide portion is a shell portion for winding and winding the rolled material. When the rolled material is introduced into the furnace coiler and its tip is penetrated into the substantially cylindrical shape by the guide portion, the mandrel starts rotating in a direction so as to give a bending force to the tip. As a result, the rolled material is sequentially wound around the shell portion with the tip caught in the mandrel.

[0005]

The above-mentioned prior art has the following problems.

(A) When a rolled material is wound by a drum-shaped deformable mandrel, the rolled material is usually wound while applying an arbitrary tension to the mandrel, and therefore a tightening force is applied to the mandrel. Since this tightening force is generated only within the plate width range of the rolled material, a large tightening force is applied within the plate width range of the substantially cylindrical mandrel, and both axial end portions outside the plate width range. Tightening force is not applied in the vicinity. In the mandrel according to the above conventional technique, the thickness of the shell portion is equal in the circumferential direction and also in the axial direction. Therefore, in particular, the central portion in the axial direction is most likely to be deformed and the amount of deformation is large, whereas the deformation hardly occurs in the vicinity of both end portions in the axial direction. Due to such a difference in the amount of deformation depending on the axial position of the mandrel, the mandrel is deformed into a substantially drum shape.

(B) Anomalous deformation such that the opening is reduced. Further, since the substantially cylindrical shape of the mandrel is not continuous in the circumferential direction, and the position of the opening becomes a discontinuous portion, the above-mentioned tightening force is required. When is operated, a distorted deformation (anomalous deformation) is likely to occur as it bends inward from the position farthest from the opening in the circumferential direction (= the position on the opposite side of the opening across the mandrel axis). . Since the mandrel according to the above-mentioned conventional technique does not pay particular attention to the suppression of this abnormal deformation, this deformation narrows the circumferential width of the opening. In particular, it becomes noticeable in the central portion of the mandrel where the deformation amount is originally large in the axial direction.

(C) Asymmetrical Deformation Further, the guide portions located on both sides in the circumferential direction of the opening have higher rigidity than the shell portion having a simple cylindrical shape because of the function of guiding the tip of the rolled material. Therefore, when the above-described tightening force is applied, the shell portion adjacent to the side opposite to the opening of the guide portion becomes a portion having a relatively low rigidity and is likely to be deformed to be recessed inward. Also at this time,
When introducing the rolled material tip into the mandrel, the guide portion does not introduce the tip toward the axial center position but rather introduces it at a position deviated from the axial center position to the front side in the introduction direction. Of the two guide parts, the one located on the rear side is more rigid than the one located on the front side in the introduction direction. Therefore, the difference in rigidity between the guide portion and the adjacent shell portion on the rear side in the introduction direction is larger than the difference in rigidity between the guide portion and the adjacent shell portion on the front side of the pass line.

Since the mandrel according to the above-mentioned prior art does not pay particular attention to such a deviation in rigidity between the front side and the rear side of the pass line, the difference in deformation between the guide portion and the adjacent shell portion is large on the front side of the pass line. Although not present, the guide portion is not significantly deformed on the rear side of the pass line and only the adjacent shell portion is largely recessed, which causes asymmetric deformation on the front and rear sides.

If the rolled material is wound in a state where the mandrel is deformed in various manners as described above in (a) to (c), there is a possibility that vibration such as meandering of the rolled material or fluctuation of tension may be induced. , Hinders the quality improvement of rolled material. In particular, when the deformation (b) occurs, the width of the opening in the circumferential direction becomes narrower, which makes it difficult to insert the rolled material into the mandrel, and there is a possibility that rolling will be hindered.

In order to suppress the above-mentioned problems as much as possible, conventionally, the deformed mandrel has been circularly ground to be in a state close to a perfect circle and reused. However, in this case, the mandrel must be replaced earlier, which makes it difficult to continuously use the mandrel for a long time. Also,
Considering the shell thickness and the like in view of structural strength, it is difficult to grind into a perfect circle.

An object of the present invention is to provide a mandrel for a furnace coiler and a furnace coiler for the mandrel capable of suppressing deformation of the mandrel due to a tightening force during winding while ensuring long-term use of the mandrel and improving quality of rolled material. To provide rolling equipment.

[0013]

(1) In order to achieve the above object, the present invention is provided in a furnace coiler,
A substantially cylindrical shell portion, an opening portion arranged in the axial direction as a circumferentially discontinuous portion of the shell portion, and first and second rolling material introduction members located on both sides in the circumferential direction of the opening portion, respectively. In the mandrel for a furnace coiler having a guide part, the first guide part is arranged on the rear side in the rolled material introduction direction, and the second guide part is arranged on the front side in the rolled material introduction direction. The thickness T1 of the portion of the shell portion adjacent to the side opposite to the opening of the first guide portion is the thickness T2 of the portion adjacent to the side opposite to the opening of the second guide portion. Thicker than.
The guide portions located on both sides of the opening in the circumferential direction have higher rigidity than the shell portion having a simple cylindrical shape because of the function of guiding the tip of the rolled material. Therefore, when the tightening force is applied, a portion of the shell portion adjacent to the guide portion on the side opposite to the opening portion becomes a portion having relatively low rigidity, and is likely to be deformed abnormally such that it is recessed inward. Further, at this time, when introducing the rolled material tip into the mandrel, the guide portion does not introduce the tip toward the axial center position, but rather toward a position deviated from the axial center position to the front side in the rolled material introduction direction. Because of the introduction, the first guide portion located on the rear side is structurally more rigid than the second guide portion located on the front side in the introduction direction. Therefore, the difference in rigidity between the first guide portion and the adjacent shell portion on the rear side in the introduction direction is larger than the difference in rigidity between the second guide portion and the adjacent shell portion on the front side in the introduction direction. That is, asymmetrical deformation occurs on the front side and the rear side in the introduction direction.

In the present invention, accordingly, the wall thickness T1 of the portion of the first guide portion adjacent to the non-opening portion side is set to the thickness of the portion of the second guide portion adjacent to the non-opening portion side. Make it thicker than T2. Accordingly, the rigidity of the portion of the shell portion adjacent to the first guide portion can be relatively improved, and the difference in rigidity between the shell portion and the first guide portion can be reduced. Therefore, the difference in rigidity between the first guide portion and the adjacent shell portion on the rear side in the introduction direction can be made close to the difference in rigidity between the second guide portion and the adjacent shell portion on the front side in the introduction direction. It is possible to make the deformation behaviors on the rear side and the front side in the rolling material introduction direction substantially equal to each other so as to be symmetrical, and to suppress the occurrence of asymmetrical deformation.

(2) In the above item (1), preferably,
When the length of the first guide portion in the introduction direction of the rolled material is L2 and the wall thickness in the direction perpendicular to the introduction direction is T4, T1≤L2≤6 * T4.
The larger the length L2 of the first guide portion in the rolling material introduction direction is, the stronger the rigidity becomes. However, by setting this L2 to be 6 times or less of the wall thickness T4 in the direction perpendicular to the introduction direction, the first guide The rigidity of the part can be made relatively small. As a result, the difference in rigidity between the first guide portion and the adjacent shell portion on the rear side in the rolling material introduction direction can be reduced, and therefore the difference in rigidity between the second guide portion and the adjacent shell portion on the front side in the introduction direction can be further reduced. You can get closer.
Further, at this time, by setting T1 ≦ L2, it is possible to ensure the original function of the first guide portion that smoothly introduces the rolled material.

(3) In the above (1), and more preferably, the angle formed by the side wall surface of the opening of the first guide portion with respect to the radial direction is 40 ° or less. As the angle of the first guide portion with respect to the radial direction of the opening side wall surface increases, the inclination of the first guide portion becomes closer to the circumferential direction and the rigidity becomes weaker. Can be suppressed more. However, at this time, if the angle is too large, the opening is narrowed and the original function of smoothly introducing the rolled material is impaired. Therefore, the angle formed by the first guide portion with respect to the radial direction of the side wall surface of the opening is set to 40 degrees.
By setting it to be at most 0, it is possible to further suppress the above-mentioned asymmetrical deformation while ensuring smooth introduction of the rolled material.

(4) In order to achieve the above-mentioned object, the present invention is also provided in a furnace coiler, and is arranged in the axial direction as a substantially cylindrical shell portion and a circumferentially discontinuous portion of the shell portion. In a mandrel for a furnace coiler having an opening and first and second guides for introducing rolled material which are respectively located on both sides in the circumferential direction of the opening, a mandrel for a furnace coiler, in the shell part, a circumferential direction from the opening. The thickness T3 of the farthest portion is defined as the average thickness Tm of the shell portion in the entire circumferential direction.
Make it larger than ean. The substantially cylindrical shell of the mandrel is not continuous in the circumferential direction, and the position of the opening is discontinuous, so that when the tightening force is applied, the part farthest from the opening in the circumferential direction (= mandrel axis) An abnormal deformation that bends inward is likely to occur from a position (on a side substantially opposite to the opening across the opening) as a base point. In the present invention, accordingly, the wall thickness T3 at the farthest portion in the circumferential direction from the opening is made larger than the wall thickness Tmean of the shell portion in the entire circumferential direction. That is, in the entire shell portion, at least the portion farthest from the opening in the circumferential direction is made relatively rigid. Thereby, the abnormal deformation can be suppressed.

(5) In the above item (4), preferably,
The shell further has a first rib extending in the circumferential direction at least at one position in the axial direction of the inner circumference of the shell portion, and a radial height of a portion farthest from the opening in the circumferential direction in the first rib. The height H1 is made larger than the radial height H2 of the portion located near the opening. Accordingly, the rigidity of the shell portion in the portion farthest in the circumferential direction from the opening portion can be further increased, and thus abnormal deformation can be further suppressed.

(6) In order to achieve the above object, the present invention is also provided in a furnace coiler, and is provided with a substantially cylindrical shell portion and an axially discontinuous portion of the shell portion in the circumferential direction. A furnace mandrel for a furnace coiler having an opening and first and second guides for rolling material introduction that are located on both sides of the opening in the circumferential direction. Further having a plurality of first ribs respectively extended to
The axial thickness Tb1 of one of the plurality of first ribs located at a position corresponding to the inside of the strip width of the rolled material is the axial thickness of the one located at a position corresponding to the outside of the strip width of the rolled material. The thickness is made larger than Tb2. Since the tightening force on the mandrel is generated only within the plate width range of the rolled material, a large tightening force is applied within the plate width range of the substantially cylindrical shell part, and the axial direction is outside the plate width range. Tightening force is not applied near both ends. In the present invention, accordingly, the first rib is extended in the circumferential direction at a plurality of positions in the axial direction on the inner circumference of the shell portion, and among the plurality of first ribs, within the plate width of the rolled material. The axial thickness Tb1 of the corresponding one is made larger than the axial thickness Tb2 of the one corresponding to the outside of the strip width of the rolled material.
As a result, the rigidity of the portion of the shell portion within the plate width range can be made relatively larger than that of the portion outside the plate width range, so that the difference in the amount of deformation due to the axial position is reduced, and the mandrel is reduced. Can be suppressed from deforming into a substantially drum shape.

(7) In order to achieve the above object, the present invention also has a rolling mill and furnace coilers provided at the inlet side and the outlet side of the rolling mill, respectively, and the furnace coiler is a rolling mill. In a rolling facility equipped with a mandrel for winding and unwinding a material, any one of the above (1), (4) and (6) is provided as the mandrel.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to the drawings. The present embodiment is an embodiment when the present invention is applied to a Steckel mill rolling facility.

FIG. 2 is a side sectional view showing a structure of a Steckel mill rolling equipment having a furnace coiler equipped with a mandrel and a rolling mill according to this embodiment, and FIG. 3 is a transverse sectional view taken along the line III-III in FIG. Is.

In FIGS. 3 and 2, the Steckel mill uses a high-temperature rolled material (steel strip) 1 at the upper and lower working ports 2.
Reversible finishing mill 2 capable of reversibly rolling between U and 2L
And the adjacent table roller 3 to assist it
And a pinch roller 4 as a conveying means capable of biting the rolled material 1, and both the inlet side and the outlet side of the reversible finishing rolling mill 2 in order to retain or heat the rolled material 1 during rolling. Furnace coilers 5 and 5 provided (however, only one is shown in FIG. 2), a lower guide 7 for introducing the rolled material 1 into the furnace coiler 5, and the rolled material 1.
And an upper guide guide 8 for introducing into the mandrel 6 (described later).

The pinch roller 4 is a rolled material 1 to the rolling mill 2 side (left side in FIG. 2) and the anti-rolling mill 2 side (right side in FIG. 2).
The above-mentioned transportation is alternately repeated. In detail,
For example, a roller is pressed when the rolled material 1 is passed through the rolling mill 2, and an upper roller is released during winding and unwinding of the rolled material 1 (described later).

The furnace coiler 5 has a mandrel 6 for introducing the rolled material 1 from an opening 66 (described later) for rewinding, and heating for heating or keeping heat of the rolled material 1 during winding by the mandrel 6. Means (for example, burner) 9, upper furnace body 13 and lower furnace body 14, and these furnace bodies 13, 14
And a pedestal 15 for supporting the. At this time, the lower furnace body 14 is provided with a rolled material opening 16 for taking in and out the rolled material 1, and the upper furnace body 13 is provided with a chimney 17 for exhausting exhaust gas in the furnace. Has been.

Needless to say, the other furnace coiler 5 (not shown) and the structure between the furnace coiler 5 and the reversible finishing mill 2 are similar.

In the Steckel rolling facility having the above structure,
When reversibly rolling the rolled material 1, the bar material rolled by the rough rolling machine (not shown) located on the upstream side of the pass line is the table roller (not shown, but the table roller 3 in FIG. 2).
(Almost the same as the above). The leading portion of the rolled material 1 which has been passed through the rolling machine 2 to the right in FIG. 2 and which has undergone the first pass rolling is conveyed by the table roller 3. At this time,
The lower guide guide 7 that has descended on the same plane as the table roller 3 rises, and the upper guide guide 8 located at the tip of the lower guide guide 7 also rises and is sent from the reversible finishing mill 2 by the pinch roller 4. The rolled material 1 is guided into the furnace coiler 5 above the pass line of the table roller 3 and further into the opening 66 as the meshing portion of the mandrel 6 in the furnace coiler 5.

When the tip of the rolled material 1 guided is inserted into the opening 66 of the mandrel 6, the mandrel 6 rotates in the clockwise direction in FIG. 2 at a speed synchronized with the strip passing speed of the rolled material 1. Wrap material 1. In this way, while rolling the rolled material 1 around the mandrel 6, the rolled material 1 is wound into the furnace coiler 5 in a coil shape while applying tension to the rolled material 1. When the winding is started, the upper guide 8 is lowered so as not to interfere with the rolled material 1.

After that, when the trailing end of the rolled material 1 slips out of the rolling mill 2, the rolling mill 2 and the furnace coiler 5 are reversed to perform the second pass rolling. That is, the rolled material 1 wound by the furnace coiler 5 is unwound, and the rolling mill 2 passes the rolled material 1 to the left in FIG. 2 to perform the second pass rolling.
The rolled material 1 is rolled up by the furnace coiler 5 on the opposite side (not shown) in the same manner as above.

After the above-described forward and reverse rolling is repeated several times by the rolling mill 2 to obtain a predetermined product plate thickness, the rolled material 1 is coiled by a finish winder (not shown) provided on the downstream side of the pass line. Roll up.

FIG. 1 is a horizontal sectional view showing the detailed structure of the mandrel 6 which is the main part of this embodiment, and FIG. 4 is a partially enlarged vertical sectional view of the portion A in FIG. In FIGS. 1, 3, and 4, a shaft 10 is arranged at the center of the mandrel 6, and both ends of the shaft 10 are rotatably supported by bearings 11. A gear coupling 12 is attached to one end surface (right side in FIG. 3) of the shaft 10. By transmitting a rotary driving force from a rotary driving means (motor) (not shown) to the gear coupling 12. , The mandrel 6 is adapted to rotate. Further, in FIG. 3, Ba indicates the inside of the rolled material plate width, and Bb indicates the outside of the rolled material plate width. The mandrel 6 winds the rolled material 1 in a region of the rolled material plate width Ba in the axial direction. The rolled material 1 does not come into direct contact with the rolled material 1 outside the rolled material width Ba outside the rolled material width Bb.

The mandrel 6 is, as shown in FIG.
The shell 61 is provided with a substantially cylindrical shape, and the shell 61 is further provided with vertical ribs 62 and horizontal ribs 63 for reinforcing the strength. The vertical rib 62 has a substantially ring shape,
Along the inner circumferential surface of the mandrel 6, the inner circumferential surface of the mandrel 6 is circumferentially extended at a plurality of axially spaced locations at arbitrary intervals. The horizontal ribs 63 are axially extended at a plurality of circumferentially spaced positions on the inner peripheral surface of the mandrel 6 at intervals between the plurality of vertical ribs 62. That is, as shown in FIG. 4, for the shell 61 having the shell thickness Ta, the rib thickness Tb
The vertical ribs 62 are provided so that the rib height is Ha (Ha> Ta). The horizontal rib 63 has a rib height Hb (Ha> H).
It is attached so that b> Ta).

Further, the mandrel 6 has a substantially rectangular opening 66 arranged axially as a circumferentially discontinuous portion of the shell portion 61, and rolling material introductions located on both sides of the opening 66 in the circumferential direction. A long guide 64 and a short guide 65 are provided. At this time, the long guide 64 on the rolling mill 2 side (= rear side in the rolling material 1 introduction direction) and the short guide 65 on the non-rolling mill 2 side (= front side in the rolling material 1 introduction direction) do not have the same shape. The shapes are different from each other as shown in FIG. Then, after the rolled material 1 is inserted into the opening 66, the entire mandrel 6 rotates clockwise to reversely bend the rolled material 1 to hook the rolled material 1 on the short guide 65, and thereafter, the mandrel 6 Rolled material 1 on the outer peripheral surface of the shell portion 61 of
It is designed to be wound up.

The most significant feature of the mandrel 6 according to the present embodiment is a drum-shaped deformation, an abnormal deformation in which the opening is reduced,
In order to suppress the occurrence of various types of deformation such as asymmetrical deformation, various considerations have been given to the dimensions of the shell 61, the long guide 64, the short guide 65, the vertical ribs 62, and the horizontal ribs 63. Below are the dimensions of each of these parts.
The operation will be described in detail.

(1) Structure for suppressing asymmetrical abnormal deformation (1-A) Shell thickness In the mandrel 6 of this embodiment, first, the shell 61 has a non-uniform thickness Ta in the circumferential direction. Of the 61, the thickness Ta = T1 of a portion 61a of the long guide 64 adjacent to the side opposite to the opening 66 is larger than the thickness Ta = T2 of a portion 61b of the short guide 65 adjacent to the side opposite to the opening 66. (For example, T1≈85 mm, T2≈60 mm). This has the following significance.

The long and short guides 64 and 65 located on both sides of the opening 66 in the circumferential direction guide the leading end of the rolled material 1,
The rigidity is stronger than that of the shell 61 having a simple cylindrical shape. Therefore, when the rolled material 1 receives a tightening force during winding of the rolled material, the guide 6 of the shell 61
Portions 61a, 61 adjacent to the side opposite to the opening 66 of 4, 65
b is a portion having a relatively low rigidity and is likely to be deformed abnormally such that it is recessed inward. At this time, the guides 64, 65
Is when the tip of the rolled material 1 is introduced into the mandrel 6,
Since the tip portion is not introduced toward the axial center position (that is, the center of the shaft 10) P, but is introduced toward a position deviated to the front side (the right side in FIG. 1) of the rolled material introduction direction from the axial center position P. , The short guide 6 which is structurally located on the front side in the introduction direction.
The long guide 64 located on the rear side (left side in FIG. 1) of 5 has a higher rigidity. Therefore, the long guide 64 and the shell adjacent portion 61a on the rear side in the introduction direction
The difference in rigidity between the short guide 65 on the front side in the introduction direction is
Becomes larger than the difference in rigidity between the shell adjacent portion 61b and the amount of deformation also depends on such rigidity behavior. The behavior of abnormal deformation as described above is shown in FIG. FIG. 5 is an analysis of how the outer shape of the shell 61 of the mandrel 6 changes due to the above-described abnormal deformation, and the thin solid line of the substantially circular shape represents the outer shape of the shell 61 before the abnormal deformation. The solid line represents the outer shape of the shell 61 after being deformed. For reference, the positions of the long and short guides 64.65 are also shown by broken lines. In FIG. 5, as described above, it can be seen that the portions 61a and 61b of the guides 64 and 65 which are adjacent to the side opposite to the opening 66 are recessed inward. Further, in particular, on the front side in the rolling material introduction direction, the difference in deformation amount between the short guide 65 and the shell adjacent portion 61b is not so large, whereas on the rear side in the rolling material introduction direction, the long guide 64 does not deform much but the shell adjacent portion It can be seen that the portion 61a is significantly deformed and there is a large difference in the amount of deformation. That is, as shown in FIG. 5, asymmetrical deformation occurs on the front side and the rear side in the rolling material introduction direction.

In the mandrel 6 of this embodiment, accordingly, the thickness T1 of the portion 61a of the shell 61 adjacent to the side of the long guide 64 on the side opposite to the opening 66 is made equal to the thickness T1 of the short guide 65. Thickness T2 of the portion 61b adjacent to the side
Thicker than. Accordingly, the rigidity of the portion 61a of the shell portion 61 adjacent to the long guide 64 can be relatively improved, and the difference in rigidity with the long guide 64 can be reduced. Therefore, the long guide 64 on the rear side in the introduction direction
Since the difference in rigidity between the shell adjacent portion 61a and the shell adjacent portion 61a can be made close to the difference in rigidity between the short guide 65 and the shell adjacent portion 61b on the front side in the introduction direction, the deformation behavior on the rear side / front side of the rolled material introduction direction. Can be made substantially equal to each other to make them symmetrical and suppress the occurrence of asymmetrical deformation.

(1-B) Length and Thickness of Long Guide Portion In the mandrel 6 of this embodiment, the length L2 of the long guide 64 in the rolling material introduction direction is defined by the direction perpendicular to the rolling material introduction direction. The thickness T1 of the shell adjacent portion 61a is not more than 6 times the thickness T4 of
I am trying to be above. That is, T1 ≦ L2 ≦ 6 ×
It is configured to be T4. This has the following significance.

The longer guide 64 has a higher rigidity as the length L2 in the rolling material introduction direction is larger. As described above, if the rigidity difference between the long guide 64 and the shell adjacent portion 61a is large, asymmetrical deformation is caused. Therefore, it is preferable to reduce the rigidity of the long guide 64 as much as possible. The inventors of the present application variously changed the length L2 in the rolling material introduction direction, analyzed the behavior of the deformation of the entire shell 61 at that time, and obtained the deformation behavior as shown in FIG. Although not shown, it has been found that the rigidity of the long guide 64 can be made sufficiently small by setting this L2 to be not more than 6 times the wall thickness T4 of the long guide 64 in the direction perpendicular to the rolling material introduction direction. That is, by setting L2 ≦ 6 × T4, the difference in rigidity between the long guide 64 and the shell adjacent portion 61a on the rear side in the rolling material introduction direction can be made sufficiently small, and the short guide 65 and the shell adjacent portion on the introduction direction front side can be sufficiently reduced. It is possible to more reliably approach the difference in rigidity with 61b.

On the other hand, the longer guide 64 can improve the original function of smoothly introducing the rolled material 1 as the length L2 in the rolled material introduction direction is larger. Therefore, if the length L2 of the long guide 64 is made too small for the purpose of suppressing the asymmetric deformation as described above, the function of introducing the rolled material deteriorates. Therefore, the length L2 of the long guide 64 is made too small. Not too much is preferred. The inventors of the present application have variously changed L2 and studied the introduction guide function of the rolled material 1. As a result, although not particularly shown, if this L2 is set to the shell adjacent portion 61a or more, introduction of the rolled material of the long guide 64 will be described. It turned out that the function can be fully secured. That is, by setting T1 ≦ L2, it is possible to ensure the original function of the guide 64 that the rolled material 1 is smoothly introduced.

From the above, by setting T1≤L2≤6 × T4, the rigidity of the long guide 64 and the shell adjacent portion 61a on the rear side in the rolling material introduction direction is ensured while ensuring the function of introducing the rolled material 1 of the long guide 64. Difference can be made sufficiently small, and the short guide 65 and the shell adjacent portion 6 on the front side in the introduction direction.
The difference in rigidity from 1b is more reliably approached to improve the rigidity balance between the rear side and the front side of the rolled material introduction direction,
It is possible to more reliably suppress the occurrence of asymmetrical deformation.

(1-C) Angle of Long Guide Portion Further, in the mandrel 6 of this embodiment, the long guide 64
The angle θ (see FIG. 1) formed by the opening with respect to the radial direction of the side wall surface 64a (line segment PQ in FIG. 1) is set to 40 ° or less.
This has the following significance.

The long guide 64 has an opening side wall surface 64a.
The larger the angle θ with respect to the radial direction of the
Since the inclination of 4 becomes closer to the circumferential direction and the rigidity becomes weaker, the asymmetric abnormal deformation described above can be suppressed more reliably. However, at this time, if the angle θ becomes too large, the width L1 of the opening 66 becomes narrow, which impairs the original function of smoothly introducing the rolled material 1. The inventors of the present application have studied the introduction guide function of the rolled material 1 by changing θ variously, and as a result, although not particularly shown, if this θ2 is set to 40 ° or less, the function of introducing the rolled material of the long guide 64 is sufficient. It turned out that it can be secured. That is, θ2 ≦ 40 °
By so doing, the difference in rigidity between the long guide 64 and the shell adjacent portion 61a on the rear side in the rolling material introduction direction can be further reduced while ensuring the smooth introduction of the rolled material 1, and the asymmetric abnormal deformation described above occurs. Can be suppressed more reliably.

(1-D) Length of Short Guide Section Furthermore, in the mandrel 6 of this embodiment, the short guide 65 is provided.
The length L3 in the rolling material introduction direction is set to be longer than that of an ordinary mandrel of this type. As a result, the rigidity of the short guide 65 having a relatively small rigidity can be increased, so that the rigidity of the guides 64, 65 on both sides can be made more uniform, and it is more certain that the above-mentioned asymmetrical deformation occurs. Can be suppressed.

(2) Structure for suppressing abnormal deformation such that the opening is reduced (2-A) Shell portion thickness In the mandrel 6 of the present embodiment, the shell 61 extends in the circumferential direction from the opening 66. Wall thickness of the farthest portion 61c Ta =
T3 is larger than the average thickness Tmean in the circumferential direction of the shell 61 (for example, T3≈70 mm). This has the following significance.

Since the substantially cylindrical shell 61 of the mandrel 6 is not continuous in the circumferential direction and the position of the opening 66 is a discontinuous portion, when the tightening force acts when winding the rolled material, the shell 61 is opened in the circumferential direction. The part farthest from the part 66 (= axis 10
(A position approximately opposite to the opening 66 across the center of the) 6
Anomalous deformation such as bending inward from 1c is likely to occur (see also FIG. 5 described above). In the mandrel 6 of this embodiment, accordingly, the opening 6 of the shell 61 is
6 is the wall thickness T3 of the farthest portion 61c in the circumferential direction from the wall thickness Tmean of the shell portion in the entire circumferential direction (the wall thickness of the portion Ta = T
3, Ta = T1 of the long guide adjoining portion 61a, and Tb = T2 of the short guide adjoining portion 61b, etc., which is larger than the average value of the entire circumferential region (in this case, Tmean = 68 mm). As a result, the rigidity can be relatively increased in at least the farthest portion 61c in the circumferential direction in the entire shell 61. It is possible to suppress abnormal deformation such that the opening 66 is reduced.

(2-B) Vertical Rib Height Further, in the mandrel 6 of this embodiment, the height Ha of the vertical ribs 62 is made nonuniform in the circumferential direction, and the vertical ribs 62 have the highest height in the circumferential direction from the opening 66. Radial height of the distant portion 62a Ha = H1
Is larger than the radial height Ha = H2 of the portion 62b located near the opening 66. This allows the shell 6
Since the rigidity of the portion 61c farthest from the opening 66 in the circumferential direction of 1 can be further increased, the opening 6
It is possible to further suppress abnormal deformation such that 6 is reduced.

Instead of the above, the thickness T of the vertical rib 62 is
b may not be uniform in the circumferential direction, and may be thicker in the vicinity of the farthest circumferential portion 61c than in other portions. Further, of the lateral ribs 63 provided at a plurality of positions in the circumferential direction, the farthest portion 61c in the circumferential direction.
The height Hb and the wall thickness of those provided in the vicinity may be made larger than those provided in other positions.

(3) Structure for suppressing drum-like deformation (3-A) Thickness of vertical ribs In the mandrel 6 of this embodiment, of the vertical ribs 62 provided at a plurality of positions in the axial direction, the rolled material 1 is the same. The axial thickness Tb = Tb1 of the plate within the strip width range Ba is larger than the axial thickness Tb = Tb2 of the rolled material 1 outside the strip width range Bb. This has the following significance.

Since the tightening force acting on the mandrel 6 is generated only within the plate width range Ba of the rolled material 1, a large tightening force is applied within the plate width range Ba of the shell 61, for example, in the vicinity of both axial end portions. For example, the tightening force is not applied to the outside of the plate width range Bb. In the mandrel of this embodiment, accordingly, the axial wall thickness Tb1 of the plurality of vertical ribs 62 within the rolled material plate width Ba is larger than the axial wall thickness Tb2 of the plurality of vertical ribs 62 outside the plate width Bb. Enlarge. As a result, the rigidity of the portion of the shell 61 within the plate width range Ba can be made relatively larger than the rigidity of the portion outside the plate width range Bb. Therefore, it is possible to reduce the difference in the deformation amount of the shell 61 depending on the axial position, and to suppress the deformation of the mandrel 6 into a substantially drum shape.

As described in (1) to (3) above, according to the present embodiment, the thickness Ta of the shell 61 is changed, the guides 64 and 65 on both sides of the opening are changed, the vertical ribs 62 are changed, etc. By performing the above, it is possible to reduce the deformation of the mandrel 6 by eliminating the bias in the rigidity of the entire mandrel 6 and making the rigidity more uniform. Also, when deformed, it is deformed into a circular shape, and it is possible to improve the distorted abnormal deformation. Therefore, since it is possible to reduce the possibility of inducing vibration or the like due to meandering of the rolled material 1 or fluctuations in tension in the Steckel mill rolling facility, it is possible to manufacture high quality products. Further, since it is not necessary to perform the circular grinding which has been conventionally performed, it becomes possible to prolong the life of the mandrel 6, and an economically good effect can be obtained.

Among the above effects, the effect of suppressing abnormal deformation will be described more specifically with reference to FIG. Figure 6
It shows the analysis result of the stress analysis in the outer peripheral portion by FEM on the axial center cross section of the mandrel 6. Taking the tensile stress on the + side of the vertical axis and the compressive stress on the-side,
The horizontal axis indicates the circumferential positions (symbols A to G) on the outer circumference of the mandrel. For comparison, the thickness of the shell 61 is uniform over the entire circumference, and the length L2 of the long guide 64 in the rolling material introduction direction is larger than 6 times the wall thickness T4 in the direction perpendicular to the rolling material introduction direction ( That is, L2> 6 × T
4), angle θ of opening side wall surface 64a of long guide 64> 4
A case where the length of the short guide 65 is 0 ° as usual (without consideration of improvement of rigidity) and the height and wall thickness of the vertical ribs are all uniform is shown as a comparative example in FIG.

(I) Stress Distribution in Comparative Example In FIG. 6, in the stress distribution of the comparative example represented by the chain double-dashed line, first, in the shell 61, the anti-opening portion 6 of the long guide 64 is formed.
A strong compressive stress is generated in the portion 61a (near F) adjacent to the 6th side. This compressive stress is stronger in the rigidity from the opening 66 of the shell 61 to the farthest portion 61c and the rigidity of the long guide 64 than the rigidity of the shell adjacent portion 61a against the tightening force applied in the radial direction of the mandrel. , Due to the difference in rigidity, the shell adjacent portion 61a
Is subject to compressive stress. Also, the short guide 6
A strong compressive stress is also generated in the portion 61b (near B) adjacent to the side opposite to the opening 66 of No. 5. From these,
As described in (1) above, the portions 61 a and 61 b adjacent to the side opposite to the opening 66 of the guides 64 and 65 are the guides 6.
It can be seen that the behavior of denting inwardly of 4,65 is supported. At this time, since the compressive stress is significantly larger in the vicinity of F than in the vicinity of B, the difference between the deformation amounts of the short guide 65 and the shell adjacent portion 61b on the front side in the rolling material introduction direction is compared with that of the rolled material. It can be seen that the difference in the amount of deformation between the long guide 64 and the shell adjacent portion 61a on the rear side in the introduction direction becomes large, which causes a different deformation.

Further, in FIG. 6, the portion 61c farthest from the opening 66 of the shell 61 (= the opposite side of the opening 66 across the center of the shaft 10) (near D) is subjected to a strong tensile stress. I understand. As a result, as described in (2) above, when a tightening force is applied during winding of the rolled material, an abnormal deformation occurs such that the farthest portion 61c serves as a base point and bends inward, so that it is pulled outward. It can be seen that various tensile stresses are acting.

(II) Stress distribution in the present embodiment In contrast to the stress distribution behavior in the comparative example as described above, in the stress distribution behavior in the present embodiment, the positions of stress peaks are almost the same as shown in FIG. However, the stress peak value is significantly reduced for both compressive stress and tensile stress.

That is, first, as described in (1) above, the thickness T1 of the portion 61a of the shell 61 adjacent to the side opposite to the opening 66 of the long guide 64 is set to the side opposite to the side opposite to the opening 66 of the short guide 65. Is made thicker than the wall thickness T2 of the portion 61b adjacent to, and the length L2 of the long guide 64 in the rolling material introduction direction is set to be not more than 6 times the wall thickness T4. As a result, the difference in rigidity between the long guide 64 (near G) and the shell adjacent portion 61a (near F) on the rear side in the rolling material introduction direction is reduced, and the compressive stress FF acting on the shell adjacent portion 61a (near F). It can be seen that (for example, about 25%) is alleviated. As a result, the compressive stress is transferred to the short guide 65 (near A) and the shell adjacent portion 61b on the front side in the introduction direction.
Shell adjacent portion 61b based on the difference in rigidity from (near B)
It is close to the value of the compressive stress FB acting on (around B). Therefore, it was found that the deformation behaviors on the rear side and the front side of the rolled material introduction direction were made substantially equal to each other to make them symmetrical and to suppress the occurrence of asymmetrical deformation.

As described in (2) above, the portion 6 of the shell 61 farthest from the opening 66 in the circumferential direction.
The thickness T3 of 1c is the average thickness Tm of the shell 61 over the entire circumferential direction.
It is larger than ean, and the radial height H1 of the farthest circumferential portion 62a of the vertical rib 62 is larger than the radial height H2 of the portion 62b located near the opening 66.
As a result, the rigidity of the outermost portion 61c (near D) of the shell 61 in the circumferential direction from the opening 66 is strengthened, and the tensile stress FD acting on the farthest portion 61c (near D) in the circumferential direction is increased (for example, about 15%). You can see that it is relaxing. Therefore, it was found that it is possible to suppress the abnormal deformation such that the opening 66 is reduced.

In the above embodiment, the short guide 6
5, the thickness T2 of the shell adjacent portion 61b on the side opposite to the opening 66
The reason why the thickness is not thickened to about 60 mm is that the balance of rigidity is taken into consideration as in the long guide 64 side. That is, for example, if the wall thickness T2 of the shell adjacent portion 61b is made thicker by about 80 mm, the compressive stress acts on the contrary due to the difference in rigidity with the short guide 65. Therefore, the thickness T2 of the shell adjacent portion 61b is not increased, but the rigidity is increased by changing the shape of the short guide 65 so as to balance the stress.

[0059]

According to the present invention, the difference in rigidity between the first guide portion and the adjacent shell portion on the rear side in the rolling material introduction direction is determined by the difference between the rigidity of the second guide portion and the adjacent shell portion on the introduction direction front side. Since the difference in rigidity can be approximated, the deformation behaviors on the rear side and the front side of the rolled material introduction direction can be made substantially equal and symmetric, and asymmetrical abnormal deformation can be suppressed. Further, in the entire shell portion, at least the portion farthest from the opening in the circumferential direction can be made relatively rigid, so that the portion farthest from the opening in the circumferential direction can be bent inwardly. Such abnormal deformation can be suppressed. Further, the rigidity of the portion within the plate width range of the shell portion can be made relatively larger than that of the portion outside the plate width range, so that the difference in the deformation amount due to the axial position is reduced, and the mandrel is It is possible to suppress the deformation into the substantially drum shape. Therefore, it is possible to reduce the possibility of inducing vibration or the like due to meandering or tension fluctuation of the rolled material, and to improve the quality of the rolled material. Further, at this time, since it is less necessary to grind the mandrel, long-term use of the mandrel can be secured.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a detailed structure of a mandrel according to an embodiment of the present invention.

FIG. 2 is a side sectional view showing the structure of a Steckel mill rolling mill having a furnace coiler equipped with the mandrel of FIG. 1 and a rolling mill.

3 is a cross-sectional view taken along the line III-III in FIG.

FIG. 4 is a partially enlarged vertical sectional view of a portion A in FIG.

FIG. 5 is a diagram showing a result of analysis as to how the outer shape of the mandrel shell changes due to abnormal deformation.

FIG. 6 is a diagram showing an analysis result obtained by FEM for stress analysis in an outer peripheral portion on a cross section of a central portion of the mandrel in the axial direction.

[Explanation of symbols]

1 Rolled material 2 Reversible finishing mill 5 Furnace coiler 6 Mandrel 61 Shell (shell part) 61a Shell adjacent part (part adjacent to the side opposite to the opening of the first guide part) 61b Shell adjacent part (second guide part) 61c Shell farthest portion (farthest portion from the opening in the circumferential direction) 62 Vertical rib (first rib) 62a Farthest portion vertical rib (farthest portion from the opening in the circumferential direction) 62b Vertical ribs Near opening (portion located near opening) 63 Horizontal rib (second rib) 64 Long guide (first guide) 64a Opening side wall surface 65 Short guide (second guide) 66 opening

Front page continuation (72) Inventor Eiji Ishikawa 3-1-1, Sachimachi, Hitachi City, Ibaraki Hitachi Ltd. Hitachi factory (72) Inventor Katsumi Totsuka 4-2 Kojimacho, Kawasaki-ku, Kawasaki-shi, Kanagawa Nihon Metallurgical Industry Co., Ltd. (72) Inventor Tsune Yamada 4-2 Kojima-cho, Kawasaki-ku, Kawasaki-shi, Kanagawa Nihon Metallurgical Industry Co., Ltd. (56) Reference JP-A-8-309436 (JP, A) -95614 (JP, U) (58) Fields surveyed (Int.Cl. ⁷ , DB name) B21C 47/00 B21B 1/32 B21C 47/28

Claims (7)

(57) [Claims] 1. A furnace portion provided in a furnace coiler, having a substantially cylindrical shape, an opening portion arranged axially as a circumferentially discontinuous portion of the shell portion, and circumferentially opposite sides of the opening portion, respectively. A mandrel for a furnace coiler having first and second guide portions for introducing rolled material located therein, wherein the first guide portion is arranged on the rear side in the rolled material introduction direction and the second guide. The portion is disposed on the front side in the rolling material introduction direction, and the wall thickness T1 of the portion of the shell portion adjacent to the side opposite to the opening portion of the first guide portion is equal to that of the second guide portion. A mandrel for a furnace coiler, which is thicker than a wall thickness T2 of a portion adjacent to the opposite opening side. 2. The furnace coiler mandrel according to claim 1, wherein the length of the first guide portion in the rolling material introduction direction is L2 and the wall thickness in a direction perpendicular to the introduction direction is T4, A mandrel for a furnace coiler, characterized in that T1≤L2≤6 × T4. 3. The furnace coiler mandrel according to claim 1, wherein the angle formed by the opening side wall surface of the first guide portion with respect to the radial direction is 40 ° or less. Mandrel. 4. A substantially cylindrical shell portion provided in a furnace coiler, an opening portion axially arranged as a circumferentially discontinuous portion of the shell portion, and circumferentially opposite sides of the opening portion, respectively. In a furnace coiler mandrel having first and second guide portions for introducing rolled material positioned therein, a wall thickness T3 of a portion farthest in the circumferential direction from the opening of the shell portion is defined as a circumference of the shell portion. Direction mean wall thickness Tmean
The mandrel for the furnace coiler, which is characterized by being made larger than. 5. The mandrel for a furnace coiler according to claim 4, further comprising a first rib extending in the circumferential direction at at least one position in the axial direction of the inner circumference of the shell portion, and the first rib. A mandrel for a furnace coiler, characterized in that a radial height H1 of a portion farthest from the opening in the circumferential direction is made larger than a radial height H2 of a portion located in the vicinity of the opening. 6. A substantially cylindrical shell portion provided in a furnace coiler, an opening portion axially arranged as a circumferentially discontinuous portion of the shell portion, and circumferentially opposite sides of the opening portion, respectively. In a furnace coiler mandrel having first and second guide portions for introducing rolled material positioned, a plurality of first ribs respectively extending in the circumferential direction at a plurality of axial positions of the inner circumference of the shell portion are further provided. Of the plurality of first ribs having the axial thickness Tb1 at a position corresponding to the inside of the strip width of the rolled material, the axial thickness Tb1 at a position corresponding to the outside of the strip width of the rolled material A mandrel for a furnace coiler, which is characterized by being made thicker than the axial wall thickness Tb2. 7. A rolling mill, and a furnace coiler provided on each of an inlet side and an outlet side of the rolling mill, and the furnace coiler includes a mandrel for winding and unwinding a rolled material. In the rolling facility, the mandrel according to any one of claims 1, 4 and 6
A rolling facility provided with the mandrel according to the item.