ROLLING MACHINE

Abstract

Rolling machine (1) includes work roll (10) that comes into contact with rolled material (K), backup roll (20) that supports work roll (10), housing (30) that accommodates work roll (10) and backup roll (20), first bearing (40) that supports work roll (10) with respect to housing (30), and second bearing (50) that supports backup roll (20) with respect to housing (30).

Claims

1. A rolling machine comprising: a work roll that comes into contact with a rolled material; a backup roll that supports the work roll; a housing that accommodates the work roll and the backup roll; a first bearing that supports the work roll with respect to the housing; and a second bearing that supports the backup roll with respect to the housing, wherein the first bearing is arranged in a first hole provided in the housing, the first hole is configured such that a first length in a first direction in which the work roll and the backup roll are arranged side by side is larger than a second length in a second direction orthogonal to the first direction, and a gap is provided between the first bearing and the first hole in the first direction.

2. The rolling machine according to claim 1, wherein the first bearing is fitted to a sleeve, the first bearing is arranged in the first hole via the sleeve, and the gap is provided between the sleeve fitted with the first bearing and the first hole in the first direction.

3. The rolling machine according to claim 1, wherein a sectional shape of the first hole is a rectangular shape, an elliptical shape, or an oval shape.

4. The rolling machine according to claim 1, wherein the housing includes a first support member and a second support member formed as different members, the first hole is provided in the first support member, a second hole is provided in the second support member, and the second bearing is arranged in the second hole.

5. The rolling machine according to claim 1, wherein the first support member includes a first portion and a second portion dividable from each other in the first hole.

6. The rolling machine according to claim 1, wherein the gap is at least a sum of a deformation amount of the backup roll, a deformation amount of the second bearing, and an approach amount between the work roll and the backup roll.

7. The rolling machine according to claim 1, wherein the gap is at least 1 mm.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0010] FIG. 1 is a perspective view illustrating a rolling machine according to a first exemplary embodiment.

[0011] FIG. 2 is a front sectional view of the rolling machine according to the first exemplary embodiment taken along line II-II.

[0012] FIG. 3 is a plan sectional view of the rolling machine according to the first exemplary embodiment taken along line III-III.

[0013] FIG. 4 is a front sectional view illustrating a gap between a first bearing and a first through-hole according to the first exemplary embodiment.

[0014] FIG. 5 is a perspective view illustrating a work roll according to the first exemplary embodiment.

[0015] FIG. 6 is a perspective view illustrating a second support member of a housing according to the first exemplary embodiment.

[0016] FIG. 7 is a front view illustrating a first support member of the housing according to the first exemplary embodiment.

[0017] FIG. 8 illustrates derivation of a gap according to the first exemplary embodiment.

[0018] FIG. 9 is a diagram corresponding to FIG. 7 according to the second exemplary embodiment.

DESCRIPTION OF EMBODIMENT

[0019] Hereinafter, exemplary embodiments of the present disclosure will be described in detail with reference to the drawings. The following description of preferred exemplary embodiments is merely illustrative in nature and is not intended to limit the present disclosure, applications thereof, or uses thereof at all.

First Exemplary Embodiment

(Rolling Machine)

[0020] Rolling machine 1 according to a first exemplary embodiment will be described. FIG. 1 is a perspective view of rolling machine 1. FIG. 2 is a front sectional view of rolling machine 1 taken along line II-II. FIG. 3 is a plan sectional view of rolling machine 1 taken along line III-III. FIG. 4 is a front sectional view illustrating gap C between first bearing 40 and first through-hole 33a to be described later. FIG. 5 is a perspective view of work roll 10 to be described later. FIG. 6 is a perspective view illustrating second support member 34 of housing 30 to be described later. FIG. 7 is a front view illustrating first support member 33 of housing 30 to be described later.

[0021] In FIG. 1, an X direction is referred to as a front-rear direction as a first direction, a Y direction is referred to as a left-right direction, and a Z direction is referred to as an upper-lower direction as a second direction. The front-rear direction (first direction), the left-right direction, and the upper-lower direction (second direction) are orthogonal to each other.

[0022] Rolled material K side to be described later in the front-rear direction (first direction) is referred to as an inner side in the front-rear direction, and a side opposite to rolled material K in the front-rear direction is referred to as an outer side in the front-rear direction. Trunk portion 11 side in an axial direction of work roll 10 to be described later in the left-right direction is referred to as an inner side in the left-right direction, and shaft portion 12 side in the axial direction of work roll 10 to be described later in the left-right direction is referred to as an outer side (side) in the left-right direction.

[0023] Rolling machine 1 rolls rolled material K. Rolled material K contains, for example, metal, resin, powder, or the like. In this example, rolled material K has a plate shape. Rolled material K is conveyed in the upper-lower direction by a conveying mechanism, and passes through rolling machine 1 on the way. In this example, rolling machine 1 is a four-stage rolling machine.

[0024] As illustrated in FIGS. 1 to 3, rolling machine 1 includes work rolls 10, backup rolls 20, housing 30, first bearings 40, second bearings 50, and sleeves 60.

[0025] As illustrated in FIGS. 1 to 3, there is one pair (two) of work rolls 10. An axial direction (axis) of work roll 10 extends in the left-right direction. Work rolls 10 are arranged side by side in the front-rear direction (first direction). Work roll 10 includes trunk portion 11 and two shaft portions 12.

[0026] Trunk portion 11 constitutes an intermediate portion of work roll 10 in the axial direction. Shaft portions 12 constitute both end portions of work roll 10 in the axial direction. An outer diameter of trunk portion 11 is larger than an outer diameter of shaft portion 12. A gap through which rolled material K passes is formed between outer peripheral surfaces of trunk portions 11 of work rolls 10. Trunk portions 11 of work rolls 10 come into contact with rolled material K.

[0027] As illustrated in FIGS. 1 to 3, there is one pair (two) of backup rolls 20. An axial direction (axis) of backup roll 20 extends in the left-right direction. Work rolls 10 and backup rolls 20 are arranged side by side in the front-rear direction (first direction and X direction). Backup rolls 20 are arranged outside work rolls 10 in the front-rear direction (on sides opposite to rolled material K). Backup roll 20 includes trunk portion 21 and two shaft portions 22.

[0028] Trunk portion 21 constitutes an intermediate portion of backup roll 20 in the axial direction. Shaft portions 22 constitute both end portions of backup roll 20 in the axial direction. An outer diameter of trunk portion 21 is larger than an outer diameter of shaft portion 22. Trunk portion 21 of backup roll 20 comes into contact with trunk portion 11 of work roll 10. Trunk portion 21 of backup roll 20 supports trunk portion 11 of work roll 10. Trunk portion 21 of backup roll 20 presses trunk portion 11 of work roll 10 inward in the front-rear direction (toward rolled material K).

[0029] As illustrated in FIGS. 1 to 3, housing 30 accommodates work rolls 10 and backup rolls 20. Housing 30 has a substantially box shape. Housing 30 includes sole plate 31, upper plate 32, first support members 33, and second support members 34. Sole plate 31, upper plate 32, first support members 33, and second support members 34 are formed as separate members, and can be divided from each other.

[0030] As illustrated in FIGS. 1 and 2, sole plate 31 has a plate shape. Through-hole 31a is formed in sole plate 31. Sole plate 31 is placed on a reference surface such as a table. Upper plate 32 has a plate shape. Through-hole 32a is formed in upper plate 32. Upper plate 32 is arranged above sole plate 31. Work rolls 10 and backup rolls 20 are arranged between sole plate 31 and upper plate 32.

[0031] Rolled material K passes through through-hole 32a of upper plate 32 from an upper side to a lower side, is rolled when the rolled material passes through a gap between work rolls 10, and is sent downward through through-hole 31a of sole plate 31.

[0032] As illustrated in FIGS. 1, 3, and 4, there are two second support members 34. Second support member 34 is arranged between sole plate 31 and upper plate 32. Second support member 34 couples sole plate 31 and upper plate 32 to each other in the upper-lower direction.

[0033] As illustrated in FIG. 6, second support member 34 is formed in a substantially U shape opened inward in the front-rear direction as viewed in the upper-lower direction. Second support member 34 includes lengthwise extension portions 34a and widthwise extension portions 34b. Lengthwise extension portion 34a has a plate shape and extends in the upper-lower direction and the left-right direction. Lengthwise extension portions 34a are arranged outside backup roll 20 in the front-rear direction.

[0034] There are two widthwise extension portions 34b. Widthwise extension portion 34b has a plate shape and extends in the upper-lower direction and the front-rear direction. Widthwise extension portions 34b are arranged inside lengthwise extension portion 34a in the front-rear direction. Widthwise extension portion 34b protrudes inward in the front-rear direction from lengthwise extension portion 34a. Widthwise extension portions 34b are arranged outside backup rolls 20 in the left-right direction (axial direction).

[0035] Second through-hole 34c as a second hole is provided in widthwise extension portion 34b of second support member 34. Second through-hole 34c penetrates widthwise extension portion 34b of second support member 34 in the left-right direction (axial direction). Second through-hole 34c corresponds to backup roll 20. A sectional shape of second through-hole 34c is a substantially perfect circular shape.

[0036] As illustrated in FIG. 4, second bearings 50 support shaft portions 22 of backup roll 20 with respect to housing 30. Two second bearings 50 are used for each backup roll 20. In this example, second bearing 50 is a rolling bearing. A sectional shape of second bearing 50 is a substantially perfect circular shape. An inner ring of second bearing 50 is fitted to shaft portion 22 of backup roll 20. An outer ring of second bearing 50 is fitted to second through-hole 34c of second support member 34 of housing 30. Protrusion 34d provided on an inner periphery of second through-hole 34c suppresses coming off of second bearing 50 in the axial direction (left-right direction).

[0037] Notch 34e is provided at a distal end portion (an inner end portion in the front-rear direction) of widthwise extension portion 34b of second support member 34. Notch 34e is provided to suppress interference with work roll 10 (see FIG. 4).

[0038] As illustrated in FIG. 3, there are four first support members 33. As illustrated in FIG. 7, first support member 33 has a plate shape and extends in the upper-lower direction and the front-rear direction. First support members 33 are arranged outside second support members 34 in the left-right direction (axial direction). First support member 33 is arranged to be displaced inward in the front-rear direction with respect to second support members 34. First support members 33 are arranged outside work rolls 10 and backup rolls 20 in the left-right direction (axial direction).

[0039] As illustrated in FIGS. 4 and 7, first support member 33 of housing 30 is provided with first through-hole 33a as a first hole and piercing hole 33b. First through-hole 33a penetrates first support member 33 in the left-right direction (axial direction). Piercing hole 33b penetrates first support member 33 in the left-right direction (axial direction). First through-hole 33a is arranged inside piercing hole 33b in the front-rear direction. First through-hole 33a corresponds to work roll 10 as will be described later. Piercing hole 33b corresponds to backup roll 20 and allows shaft portion 22 of backup roll 20 to pass therethrough.

[0040] As illustrated in FIG. 4, first bearings 40 support shaft portions 12 of work roll 10 with respect to housing 30. Two first bearings 40 are used for each work roll 10. In this example, first bearing 40 is a rolling bearing. A sectional shape of first bearing 40 is a substantially perfect circular shape. As illustrated in FIG. 5, an inner ring of first bearing 40 is fitted to shaft portion 12 of work roll 10.

[0041] An outer ring of first bearing 40 is fitted to an inner periphery of sleeve 60 having a cylindrical shape. Two sleeves 60 are used for each work roll 10. A sectional shape of sleeve 60 is a substantially perfect circular shape. An outer periphery of sleeve 60 in a state where first bearing 40 is fitted is fitted to first through-hole 33a of first support member 33 of housing 30. In other words, first bearing 40 is fitted to first through-hole 33a via sleeve 60. Sleeve 60 is interposed between first bearing 40 and first through-hole 33a. Coming off of sleeve 60 (first bearing 40) in the axial direction (left-right direction) is suppressed by protrusion 33g provided on an inner periphery of first through-hole 33a.

[0042] As illustrated in FIG. 7, first through-hole 33a is configured such that front-rear length Hx as a first length in the front-rear direction (first direction and X direction) is larger than upper-lower length Hz as a second length in the upper-lower direction (second direction and Z direction) orthogonal to the front-rear direction.

[0043] First through-hole 33a has a flat shape that is long in the front-rear direction (first direction) and short in the upper-lower direction (second direction). A sectional shape of first through-hole 33a is an elliptical shape or an oval shape having a major axis in the front-rear direction (first direction) and a minor axis in the upper-lower direction (second direction).

[0044] As illustrated in FIG. 4, gap C is provided between first bearing 40 and first through-hole 33a in the front-rear direction (first direction). More accurately, gap C is provided between sleeve 60 to which first bearing 40 is fitted and first through-hole 33a in the front-rear direction (first direction). More specifically, gap C is provided between the outer periphery of sleeve 60 and the inner periphery of first through-hole 33a in the front-rear direction (first direction).

[0045] Gap C in the front-rear direction (the sum of gaps on both sides in the front-rear direction) is preferably at least 1 mm.

[0046] The gap between sleeve 60 (first bearing 40) and first through-hole 33a in the upper-lower direction (second direction) is preferably as small as possible, and is preferably 0.

(Derivation of Gap)

[0047] Minimum necessary gap C is derived as follows. FIG. 8 illustrates derivation of gap C. Gap C is preferably at least the sum of deformation amount 12 of backup roll 20, deformation amount 3 of second bearing 50, and approach amount 4 between work roll 10 and backup roll 20 (C12+3+4).

[0048] Deformation amount 12 of backup roll 20 is generated by a rolling load against work roll 10 from rolled material K. The rolling load from rolled material K acts on backup roll 20 via work roll 10. Then, the rolling load acting on backup roll 20 is supported by two second bearings 50.

[0049] Deformation amount 12 of backup roll 20 is the sum of maximum deflection amount 1 due to bending and maximum deflection amount 2 due to shearing (12=1+2).

[0050] Maximum deflection amount 1 [mm] due to bending is expressed by [Math. 1] by deforming d.sup.2y/dx.sup.2=M/E.sub.BI. Note that, M is a bending moment [N.Math.mm], E.sub.B is a longitudinal elastic modulus (Young's modulus) [N/mm.sup.2] of backup roll 20, and I is a sectional secondary moment [mm.sup.4].

[0051] In Expression [Math. 1], a total length of backup roll 20 (accurately, a distance between two second bearings 50) L [mm], outer diameter DB [mm] of trunk portion 21 of backup roll 20, outer diameter d.sub.B [mm] of shaft portion 22 of backup roll 20, distance n [mm] from an end portion of trunk portion 21 of backup roll 20 to a support position by second bearing 50, longitudinal elastic modulus (Young's modulus) E.sub.B [N/mm.sup.2] of backup roll 20, rolling load W [N/mm] per unit length, working range b [mm] of rolling load W, and circumferential modulus were used. Note that, maximum deflection amount 1 due to bending is generated at center position (L/2) of backup roll 20.

[00001]$\begin{array}{cc}{}_1=\frac{Wb}{6D_B^4{E}_B}\left[8L^3-4L{b}^2+b^3+64n^3\left(\frac{D_B^4}{d_B^4}-1\right)\right]& \left[\mathrm{Math}.1\right]\end{array}$

[0052] Maximum deflection amount 2 due to shearing is expressed by Expression [Math. 2] by deforming =G.sub.B and using lateral elastic modulus (shear elastic modulus) G.sub.B [N/mm.sup.2]. Note that, is shear stress [N/mm.sup.2], and is shear strain [-].

[00002]$\begin{array}{cc}{}_2=\frac{Wb}{G_B{D}_B^2}\left[L-\frac{b}{2}+2n\left(\frac{D_B^2}{d_B^2}-1\right)\right]& \left[\mathrm{Math}.2\right]\end{array}$

[0053] Note that, in FIG. 8, support load A against rolling load Wb by each second bearing 50 of two second bearings 50 on backup roll 20 side is illustrated. Each second bearing 50 supports substantially half of rolling load Wb (Wb). That is, support load A by second bearing 50 is of rolling load Wb (A=Wb/2).

[0054] Deformation amount 3 [mm] of second bearing 50 is generated by support load A. Deformation amount 3 of second bearing 50 varies depending on an aspect of the bearing. For example, in a case where a roller bearing (model number 22212RZ) manufactured by JTEKT Corporation is used as second bearing 50, deformation amount 3 of second bearing 50 is expressed by Expression [Math. 3]. In Expression [Math. 3], is a nominal contact angle [], L.sub.wr is a roller effective contact length [mm], and Q.sub.MAX is a maximum rolling element load [N].

[00003]$\begin{array}{cc}{}_3=\frac{0.00018}{\cos }\frac{Q_{\mathrm{MAX}}^{{0.75}^{}}}{L_{\mathrm{wr}}^{0.5}}& \left[\mathrm{Math}.3\right]\end{array}$

[0055] Approach amount 4 [mm] between work roll 10 and backup roll 20 is expressed by Expression [Math. 4]. Expression [Math. 4] uses the Hertz contact stress theory. In Expression [Math. 4], outer diameter D.sub.W [mm] (see FIG. 5) of trunk portion 11 of work roll 10, longitudinal elastic modulus (Young's modulus) E.sub.W [N/mm.sup.2] of work roll 10, Poisson's ratio v.sub.W [-] of work roll 10, outer diameter D.sub.B [mm] of trunk portion 21 of the backup roll, longitudinal elastic modulus (Young's modulus) E.sub.B [N/mm.sup.2] of backup roll 20, Poisson's ratio v.sub.B [-] of backup roll 20, rolling load W [N/mm] per unit length, circumferential modulus , Napier's number e, and natural logarithm ln with a base being e were used.

[00004]$\begin{array}{cc}{}_4=\frac{W}{}\left(\frac{1-v_W^2}{E_w}+\frac{1-v_B^2}{E_B}\right)\left\{\mathrm{In}\frac{{}^3\sqrt{e^2}}{2\left(\frac{1-v_W^2}{E_w}+\frac{1-v_B^2}{E_B}\right)}+\mathrm{In}\left(D_w+D_B\right)-\mathrm{InW}\right\}& \left[\mathrm{Math}.4\right]\end{array}$

[0056] Necessary gap C can be obtained by using Expression [Math. 1] to Expression [Math. 4] (C12+3+4=1+2+3+4).

[0057] It is assumed that materials of work roll 10 and backup roll 20 contain SKD11. It is assumed that L=430 [mm] (L/2=215 [mm]), D.sub.B=200 [mm], d.sub.B=60 [mm], n=85 [mm], b=100 [mm], D.sub.W=60 [mm]. It is assumed that rolling load Wb is 5000 [kgf] (49000 [N]).

[0058] In this case, 1+2+3+4=about 0.12 [mm]. Thus, gap C may be secured to be at least 0.12 [mm]. Gap C is preferably secured to be at least 1 mm with a margin. In addition, from the viewpoint of the rigidity of first support member 33, gap C is preferably less than or equal to 5 mm.

Operation and Effect

[0059] As illustrated in FIG. 3, ideally, rolling load Wb applied from rolled material K to work roll 10 is almost entirely applied to second bearing 50 on backup roll 20 side and hardly applied to first bearing 40 on work roll 10 side. At this time, each second bearing 50 of two second bearings 50 on backup roll 20 side supports rolling load Wb by approximately half. Support load A against rolling load Wb by each second bearing 50 on backup roll 20 side is of rolling load Wb (A=Wb/2). Rolling load Wb acts in the front-rear direction (first direction).

[0060] Ideally, since rolling load Wb is hardly applied to first bearing 40 on work roll 10 side, support load A against rolling load Wb by each first bearing 40 of two first bearings 40 on work roll 10 side becomes 0 (A=0). In this case, deflection hardly occurs in work roll 10.

[0061] However, in practice, a part of rolling load Wb may be applied to first bearing 40 on work roll 10 side (A>0) due to a factor such as a manufacturing error, for example. In this case, deflection is likely to occur in work roll 10. When deflection occurs in work roll 10, since the deflection is transferred to rolled material K, the dimensional accuracy of the rolled material is deteriorated.

[0062] In the present exemplary embodiment, first through-hole 33a is configured such that front-rear length Hx in the front-rear direction (first direction and X direction) is larger than upper-lower length Hz in the upper-lower direction (second direction and Z direction). Then, gap C (vacancy) is provided between first bearing 40 and first through-hole 33a in the front-rear direction (first direction), which is an action direction of rolling load Wb.

[0063] Even though a part of rolling load Wb is applied to first bearing 40 on work roll 10 side, first bearing 40, sleeve 60, and work roll 10 integrally move (rotate or slide translate) in the front-rear direction (first direction) with respect to first through-hole 33a following the deflection of backup roll 20.

[0064] As a result, rolling load Wb applied to first bearing 40 on work roll 10 side can be released. Then, support load A against rolling load Wb by first bearing 40 on work roll 10 side can be set to be substantially 0 (A=0).

[0065] The deflection of work roll 10 can be suppressed in rolling machine 1. Thus, it is possible to suppress transferring of the deflection of work roll 10 to rolled material K. Then, this can suppress the deterioration in the dimensional accuracy of rolled material K. In addition, work roll 10 can be suppressed from being broken by bending stress.

[0066] Support load A against rolling load Wb by first bearing 40 on work roll 10 side is regarded as 0, and thus, the control of rolling machine 1 is simplified.

[0067] Since first bearing 40 is fitted to first through-hole 33a via sleeve 60, wear of first bearing 40 when first bearing 40 moves with respect to first through-hole 33a can be suppressed as compared with a case where first bearing 40 is directly fitted to first through-hole 33a.

[0068] The sectional shape of first through-hole 33a is formed in an elliptical shape or an oval shape having a major axis in the front-rear direction (first direction), and thus, gap C can be more easily provided between first bearing 40 (sleeve 60) and first through-hole 33a in the front-rear direction (first direction).

[0069] In housing 30, first support member 33 on work roll 10 side and second support member 34 on backup roll 20 side are divided from each other, since attachment and detachment of work roll 10 and/or backup roll 20 is facilitated, maintainability is excellent.

[0070] Gap C is at least the sum of deformation amount 12 of backup roll 20 (maximum deflection amount 1 due to bending and maximum deflection amount 2 due to shearing), deformation amount 3 of second bearing 50, and approach amount 4 between work roll 10 and backup roll 20 (C1+2+3+4). As a result, it is advantageous in reducing support load A against rolling load Wb by first bearing 40 on work roll 10 side to 0 (A=0). Then, it is advantageous in suppressing the deflection of work roll 10.

[0071] Gap C is set to be at least 1 mm, and thus, it is possible to secure gap C necessary for suppressing the deflection of work roll 10 with a margin.

Second Exemplary Embodiment

[0072] Rolling machine 1 according to a second exemplary embodiment will be described with reference to FIG. 9. FIG. 9 is a diagram corresponding to FIG. 7 according to the second exemplary embodiment. In the following description, configurations similar to those in the first exemplary embodiment are denoted by the same reference marks, and the detailed description thereof will be omitted.

[0073] As illustrated in FIG. 9, in the present exemplary embodiment, first support member 33 includes first portion 33c and second portion 33d. First portion 33c and second portion 33d can be divided from each other in the front-rear direction (first direction) in first through-hole 33a. First portion 33c and second portion 33d are separate members.

[0074] First portion 33c is arranged inside second portion 33d in the front-rear direction (first direction). First notch 33e having a substantially semi-elliptical shape is formed on an outer side of first portion 33c in the front-rear direction. First notch 33e constitutes an inner half portion of first through-hole 33a in the front-rear direction.

[0075] Second portion 33d is arranged outside first portion 33c in the front-rear direction (first direction). Second notch 33f having a substantially semi-elliptical shape is formed on an inner side of second portion 33d in the front-rear direction. Piercing hole 33b is also provided in second portion 33d. Second notch 33f constitutes an outer half portion of first through-hole 33a in the front-rear direction.

[0076] First support member 33 is formed by coupling first portion 33c and second portion 33d in the front-rear direction (first direction). First portion 33c and second portion 33d are coupled in the front-rear direction, and thus, first through-hole 33a is formed by combining first notch 33e and second notch 33f. The coupling between first portion 33c and second portion 33d is performed by a fixing member such as a bolt and a nut.

[0077] The other configurations are similar to those in the first exemplary embodiment.

[0078] According to the present exemplary embodiment, first support member 33 is divided into first portion 33c and second portion 33d in first through-hole 33a, and thus, attachment and detachment of first bearing 40 (sleeve 60) is facilitated. As a result, maintainability is excellent.

OTHER EXEMPLARY EMBODIMENTS

[0079] Although the present disclosure has been described above with the suitable exemplary embodiment, the present disclosure is not limited to the above description, and various modifications can be surely made.

[0080] First bearing 40 may not be a rolling bearing, and may be, for example, a sliding bearing or the like. The same applies to second bearing 50.

[0081] Gap C may be less than or equal to 1 mm. Gap C may be at least 5 mm.

[0082] In housing 30, first support member 33 and second support member 34 may not be formed as separate members, and may be integrally formed with each other.

[0083] The sectional shape of first through-hole 33a may not be an elliptical shape or an oval shape, and may be, for example, a polygonal shape such as a rectangular shape, a free curved shape, or the like. The same applies to an outer peripheral shape of the outer ring of first bearing 40 and an outer peripheral shape of sleeve 60.

[0084] First bearing 40 may be directly fitted to first through-hole 33a without sleeve 60.

[0085] First hole 33a may not be the through-hole, and may be, for example, a bottomed hole (that is, recess). The same applies to second hole 34c.

[0086] A pressurizing mechanism that pressurizes and presses backup roll 20 against work roll 10, a work roll bending mechanism that pressurizes work roll 10 to a side opposite to a pressurizing direction, and the like may be provided in rolling machine 1.

[0087] In deriving gap C (1+2+3+4), not only the above Expression but also a numerical simulation such as a finite element method may be used.

[0088] An intermediate roll may be interposed between work roll 10 and backup roll 20. Rolling machine 1 may not be a four-stage rolling machine, and may be, for example, a multi-stage rolling machine having another number of stages.

[0089] A feeding direction of rolled material K is not limited to the upper-lower direction, and may be, for example, the front-rear direction or the left-right direction. Rolled material K may not have a plate shape. In particular, in a case where rolled material K contains powder, rolled material K often has a shape other than the plate shape.

INDUSTRIAL APPLICABILITY

[0090] Since the present disclosure can be applied to the rolling machine, the present disclosure is extremely useful and has high industrial applicability.

REFERENCE MARKS IN THE DRAWINGS

[0091] X front-rear direction (first direction) [0092] Y left-right direction [0093] Z upper-lower direction (second direction) [0094] Hx front-rear length (first length) [0095] Hz upper-lower length (second length) [0096] C gap [0097] Wb rolling load [0098] K rolled material [0099] 1 rolling machine [0100] 10 work roll [0101] 11 trunk portion [0102] 12 shaft portion [0103] 20 backup roll [0104] 21 trunk portion [0105] 22 shaft portion [0106] 30 housing [0107] 33 first support member [0108] 33a first through-hole (first hole) [0109] 33b piercing hole [0110] 33c first portion [0111] 33d second portion [0112] 34 second support member [0113] 34c second through-hole (second hole) [0114] 40 first bearing [0115] 50 second bearing [0116] 60 sleeve