WO2012085254A1

WO2012085254A1 - Back-up roll and roll arrangement

Info

Publication number: WO2012085254A1
Application number: PCT/EP2011/073890
Authority: WO
Inventors: Karl Keller; Kurt Scheffe; Konrad Roeingh
Original assignee: Sms Siemag Ag
Priority date: 2010-12-22
Filing date: 2011-12-22
Publication date: 2012-06-28
Also published as: DE102010063828A1

Abstract

The invention relates to a back-up roll (100) for supporting a working roll (200) in a roll stand. The back-up roll comprises a roll surface (110) and roll pins (114-1, 114-2) arranged on the two end faces of the roll surface. At least in one end face of the roll surface, an annular fillet (115) open toward the end face is formed. In order to reduce or minimize the mechanical stresses in the event of rolling forces occurring during rolling operation in the area of the fillet, the contour (116) of the fillet (115) and of the transition of the fillet to the roll pin - as viewed in a longitudinal section through the back-up roll - is formed by three adjacent circular arc sections (116-1, 116-2, 116-3) having a first, second, and third radius (r₁, r₂, r₃).

Description

Back-up roll and roll arrangement

The invention relates to a support roller for supporting a work roll in a rolling stand and a roller assembly. Back-up rolls are known in the art, for example, from international patent application WO 2004/089559 or Russian patent applications RU 2 044 179 C1 and RU 2 148 737 C1. The support rollers typically comprise a roll bale and arranged on the two end faces of the roll bale roll neck, wherein at least in one end face of the roll bale an open towards the front annular groove is formed.

During a rolling process, the back-up rolls serve to support work rolls and are therefore regularly subjected to large dynamic loads, in particular bending stresses, over their entire length. The flutes in the end faces of the roll bales mean a mechanical weakening of the support rollers; Therefore, maximum stress loads occur during the rolling operation in the grooves. This means that there is the greatest risk of fracture for the support rollers in the region of the fillets. This applies at least to previously used in the prior art contours of the fillets, which contours consist of, for example, a circular arc section and at least one straight section.

Based on this prior art, the invention has the object, a known support roller and a known roller assembly with an annular groove in at least one end face of the support roller develop further to the effect that the mechanical stresses are further reduced in the rolling operation occurring in the region of the groove with occurring rolling forces. This object is with respect to the support roller by the subject of the

Claim 1 solved. This is characterized in that the contour of the groove and the transition of the groove to the roll neck - im

Longitudinal section seen through the support roller - is formed by three adjacently arranged circular arc sections having a first, second and third radius.

Experiments and simulations carried out by the Applicant have shown that, with such a contour of the groove, the stresses occurring in the region of the groove in the backing roll during the rolling operation are very clearly reduced compared with the contours known from the prior art. Thus, the risk of breakage of the backup roller is reduced, that is extended their life, and thus the Bertriebskosten be reduced for the operator.

The groove and the transition to the roll neck is in addition to the predetermined radii for the circular arc sections further defined by the fact that the transitions between each two adjacent circular arc sections and the transition between the shell of the roll neck and the first radius n at point P continuously differentiable, so smooth and transition-free , Are formed and that the desired depth t of the groove with respect to the end face of the roll bale is predetermined.

The term contour refers to a view of the groove and the transition to the roll neck or the support roll in a longitudinal section along the longitudinal axis of the support roller. Particularly advantageous size ratios for the radii of the individual arc sections are given in the dependent claims. At these radii ratios, the stresses occurring in the region of the groove are particularly low.

According to one exemplary embodiment of the invention, the contour of the roll bale of the support roll is ground back in the axial direction at least to the end face with the fillet. This re-grinding of the roll bale advantageously causes avoidance of otherwise occurring under bending stress in the region of the end faces of the roll bale maximum loads. In conjunction with the groove, which, as I said, represents a weakening of the support roller, there is otherwise, that is, without the mentioned edge regression the risk that the annular overhang of the roll bale above the groove to the outer radius of the roll bale breaks off.

It has proved to be advantageous that the regrind extends only over a certain length of length x, starting from the end face of the roll bale towards the center of the support roll. It has also proven to be advantageous that the contour of the roll bale in the axial direction is not arbitrary, but is formed in the region of the longitudinal section x by two adjacent superimposed circular arc sections. For more information on the specific configuration of the contour of the roll bale reference is made to the dependent claims.

The above-mentioned object is further achieved by a roller arrangement, wherein the roller arrangement comprises a support roller according to the invention and two bearings, in which the support roller is mounted with its roll neck. The bearings are typically each designed as plain bearings or rolling bearings. The advantages of this roller arrangement correspond to the advantages mentioned above with respect to the support roller. The description is a total of five figures attached, where

1 shows a support roller in cooperation with a work roll according to the prior art and the present

Invention;

Figure 2 is a partial view of a roller assembly; 3 shows a longitudinal section through an inventive

Back-up roll with a groove according to a first embodiment;

Figures 4a, b, c, d an explanation of the design of the contour of

Roll bale according to the present invention; and

Figure 5 is a longitudinal section through an inventive

Back-up roll with a groove according to a second embodiment; shows.

The invention will now be described in detail in the form of embodiments with reference to said figures. In all figures, the same technical elements are designated by the same reference numerals.

FIG. 1 shows a support roller 100 for supporting a work roll 200 in a rolling stand. The support roller comprises a roll bale 1 10 and at the two end faces 1 12-1, 1 12-2 of the roll bale arranged roll pin 1 14-1, 1 14-2. In at least one end face 1 12-1, 1 12-2 of the roll bale, However, typically in both end faces, in the transition region between the roll neck and the end face of the roll bale open to the front side annular groove 1 15 is formed. In Figure 1, the mechanical load occurring in the rolling operation is further symbolized by the force F. The force F, more precisely a force distribution, transfers during rolling operation from the work roll to the support roll and must ultimately be supported by bearings (not shown in FIG. 1) in which the support roll is mounted or supported by the roll stand in which the support roll is mounted. be caught. Each of the bearings at the two ends of the roller is loaded with half the force F.

Figure 2 shows a longitudinal section through the roller assembly according to the invention consisting of the support roller 200 and two bearings, of which only one bearing 300-1 is shown. The support roller is mounted with its roll neck 1 14-1 in the bearing 300-1. The bearing is exemplified in Figure 2 as a plain bearing; However, it may alternatively be designed as a rolling bearing. In the embodiment shown in FIG. 2 as a slide bearing, the slide bearing comprises a journal bushing 302-1 which is pushed in a rotationally fixed manner onto the roller journal. The roll neck 1 14-1 with the pin bushing 302-1 is rotatably mounted in a bearing bush 304-1. The bearing bush is part of a bearing housing 306-1, also called chock and rotatably connected to the chock. Between the bushing 304-1 and the pin bushing 302-1, a lubricating film is formed (not shown in Fig. 2). The chock is spaced at a distance d from the end face of the roll bale.

During the rolling operation, the lubricating film is formed between the bushing 304-1 and the journal bush 302-1 made of oil under pressure. The oil urges out of the space between the bearing bush and the pin bushing, in particular towards the end face 1 12-1 of the roll bale. At the same time, the roll barrel of the backup roll during the rolling operation is, for example, cooling water exposed, which passes through the annular gap with the width d between the roll barrel and the chock in the direction of the groove. In order to prevent mixing between the cooling water from the roller ball and the oil of the lubricating film, one or more sealing rings 308 is arranged in the region of the groove 115. Through the groove 115, the sealing rings 308 can be displaced in the direction of roll bale; This has the advantage that the distance d between the chock and the end face of the roll bale can be made very small. This has the advantage that in old systems in existing rolling stands with a predetermined width support rollers can be installed with wider bales for rolling broader products and that in new plants, the rolling stands or the roll stand can be built narrower from the outset and still the support rollers are installed with wide bales can. Figure 3 shows the configuration of the contour 116 of the groove 115 with the transition to the roll neck at the point P and the configuration of the contour 118 of the roll bale 110 according to a first embodiment. According to the invention, the contour 116 of the groove 115 is formed towards the interior of the roll bale 110 in the form of a semicircle, wherein the contour of the semicircle is formed or approximated by three adjacently arranged circular arc sections 116-1, 116-2 and 16-3. The first circular arc section has a first radius n, the second circular arc section 116-2 has a second radius r ₂ and the third circular arc section has a third radius r ₃ . The three radii can not be chosen arbitrarily according to the invention, but are each in a certain ratio to each other. Thus, the invention provides that the ratio of the first radius n to the second radius r ₂ in a value range between 1, 6 and 3.6, according to the first embodiment is preferably 2.2. At the same time, it is provided that the ratio of the second radius r ₂ to the third radius r ₃ in a value range between 0.4 and 2.5, according to the first embodiment preferably 0.56. Finally, it is provided that the ratio of the first radius n to the third radius r ₃ lies in a value range between 0.9 and 7, according to the first exemplary embodiment preferably at 1.22.

FIG. 3 further shows that the contour 1 18 of the jacket of the roll bale 1 10 of the support roll is ground back in the axial direction with respect to the end face 1 12-1 with the fillet 15. As a result, when the back-up roll is not loaded by a work roll 200, as shown in FIG. 3, the work roll no longer rests on the roll bale in the region of the end face of the roll bale. In the event of load, that is, in rolling operation, the situation changes, however, with the consequence that then the annular overhang 1 19 of the roll bale between the groove 1 15 and the back ground contour of the roll bale is increasingly loaded in the radial direction by the work roll. However, due to the regression, the radial overhang is far less stressed than without regrind.

With reference to FIGS. 3 and 4 a-d, an embodiment of the regrind for the contour 1 18 of the roll bale which is considered to be particularly favorable according to the invention is described in more detail below.

Thus, it is provided according to the invention that the regrind extends over a length of length x, starting from the end face 12-1 of the roll bale, towards the center of the support roll, with a ^» T _mi n <x <g ^» T _ma x (1) with a: weighting factor with 10 <a <50, preferably 40;

g: weighting factor of 1.5 <g <3, preferably 2.5; T _min : minimum depth of the groove in the axial direction with respect to the end face 1 12-1 of the roll bale 1 10; and

T _max : maximum depth of the groove in the axial direction with respect to the end face 1 12-1 of the roll bale 1 10.

The formula (1) shows that at least the length x, over which extends the regrind, according to the invention over the minimum and maximum depth T _min, T _{max of} the groove tuned to their particular configuration and insofar depends on this.

In FIGS. 3 and 4 a-d, the length x is assumed to be 200 mm, for example. That is, the regrind begins 200 mm from the end face of the roll bale and extends to the front side. FIG. 4a again shows the entire support roller with the coordinates x and y.

FIGS. 4 bd illustrate the realization of the regrind according to the present invention. It can be seen that the regression in the longitudinal section is formed overall by two superposed circular arc sections. In concrete terms, it can be seen in FIG. 4b that for the production of the claimed contour 1 18 initially in a first processing step of the roll barrel on its outer side starting at a distance x from the front side over the entire length x with a contour corresponding to a fifth circular arc section with a fifth radius r _{5 is} ground. This radius r ₅ may be, for example 26.66 meters. According to FIG. 4c, in a subsequent second processing step, the contour of the roll bale in the region of the front half of the longitudinal section xi, that is, for example in the range from 0 to 100 mm, is further ground back, namely in the form of a fourth circular arc section with a fourth radius r ₄ , Overall, in this way over the length x results in a total regrind contour, which is in the Length section xi of two superimposed circular arc sections r ₄ , r ₅ composed.

The radius r ₅ is preferably greater than the radius r ₄ . In the example according to FIG. 4, the radius r _{4 is} four meters. The ratio of the fifth radius _R5 to the fourth radius r ₄ is preferably 6.66.

In forming the groove with the claimed contour 116 and at the same time forming the contour 118 for the roll barrel, as just described, it is ensured that not only the risk of breakage for the support roller in the region of the transition between the end face of the roll bale and the roll neck, but also the risk of breakage for the annular overhang 119 is minimized. Figure 5 shows the configuration of the contour 116 of the groove 115 and the transition to the roll neck according to a second embodiment. Also in the second embodiment, the contour 116 of the groove 115 is formed with the transition to the roll neck by three adjacently arranged circular arc sections 116-1, 116-2 and 116-3 with the radii n, r ₂ and r ₃ .

According to the second embodiment, it is provided that the ratio of the first radius n to the second radius r _{2 is} in a value range between 1, 6 and 3.6, but by way of example at 3.0. At the same time, it is provided that the ratio of the second radius r ₂ to the third radius r _{3 is,} for example, 2.0. Finally, it is provided that the ratio of the first radius n to the third radius r _{3 is,} for example, 6.0.

The predetermined depth t of the groove is smaller in the second exemplary embodiment according to FIG. 5 than in the first exemplary embodiment according to FIG. 3. For all embodiments of the invention, in particular for the first according to FIG. 3 and the second according to FIG. 5, the transitions between each two adjacent circular arc sections and the transition at the point P between the shell of the roll neck and the first radius n are preferably each continuously differentiable , so smooth and transition-free, trained. The desired depth t of the groove relative to the end face of the roll bale is predetermined, where: T _min ^ t <T _max

With inventive design of the groove and the transition to the roll neck with these criteria, the stress distribution in the region of the groove and the transition to the roll neck and thus the risk of breakage for the support roller in the load case is minimized.

LIST OF REFERENCE NUMBERS

100 support roller

1 10 roll bales

1 12-1 Front side of the roll bale

1 12-2 Front side of the roll bale

1 14-1 Roll Cone

1 14-2 roll neck

1 15 throat

1 16 Contour of the fillet

1 16-1 arc section

1 16-2 arc section

1 16-3 arc section

1 18 Contour of roll bale

1 19 Ring-shaped overhang of the roll bale

200 work roll n first radius

r ₂ second radius

r ₃ third radius

r ₄ fourth radius

r ₅ fifth radius

P transition point from the shell of the roll neck on the circular arc section with the Radis n

g weighting factor

a weighting factor

T _min minimum depth of the groove

Tmax maximum depth of the throat

t depth of the groove relative to the front side of the roll bale

x length section over which the regrind extends

xi first, frontal part length section of the length section

Claims

claims

1 . A back-up roll (100) for supporting a work roll (200) in a rolling stand, comprising:

a roll bale (1 10); and

on the two end faces (1 12-1, 1 12-2) of the roll bale arranged roll neck (1 14-1, 1 14-2),

wherein at least in one end face (1 12-1, 1 12-2) of the roll bale an open towards the front side annular groove (1 15) is formed;

characterized,

that the contour (1 16) of the groove (1 15) and the transition of the groove to the roll neck - seen in longitudinal section through the support roller - by three adjacently arranged circular arc sections (1 16-1, 1 16-2, 1 16-3) with a first, second and third radius (n, r ₂ , r ₃ ) is formed.

2. back-up roll (100) according to claim 1,

characterized in that

the ratio of first to second radius (n, r ₂ ) in a value range between 1, 6 and 3.6;

the ratio of second to third radius (r ₂ , r ₃ ) in a value range between 0.4 and 2.5; and

the ratio of first to third radius (n, r ₃ ) in a value range between 0.9 and 7.0

lies. Support roller (100) according to claim 2, characterized in that according to a first embodiment

the ratio of first to second radius (n, r ₂ ) at 2.2;

the ratio of second to third radius (r ₂ , r ₃ ) at 0.56; and

the ratio of first to third radius (n, r ₃ ) at 1, 22

lies.

Support roller (100) according to claim 2, characterized in that according to a second embodiment

the ratio of first to second radius (n, r ₂ ) at 3.0;

the ratio of second to third radius (r ₂ , r ₃ ) at 2.0; and

the ratio of first to third radius (n, r ₃ ) at 6.0

lies.

Back-up roll (100) according to one of the preceding claims,

characterized,

that the contour (1 18) of the roll bale (1 10) of the support roller in the axial direction to the at least one end side with the groove (1 15) is ground back.

A back-up roll (100) according to claim 4 or 5,

characterized,

that the regrind extends over a length of length x, starting from the end face (1 12- 1) in the direction of the center of the

Back-up roll with a ^» T _mi n <x <g ^» T _ma x (1)

with a: weighting factor with 10 <a <50, preferably 40;

g: weighting factor of 1.5 <g <3, preferably 2.5; T _min : minimum depth of the groove in the axial direction with respect to the

End face 1 12-1 of the roll bale 1 10; and

Back-up roll (100) according to claim 6,

characterized,

in that the contour (1 18) of the roll bale (1 10) is formed in the axial direction over the length x by two adjacent circular arc sections superimposed in the regression with a fourth radius (r ₄ ) and a fifth radius (r ₅ ).

A back-up roll (100) according to claim 7,

characterized,

the fourth radius (r ₄ ) in the region of a first partial length section xi, starting at the end face of the roll bale, is smaller than the fifth radius (r ₅ ) in a second partial length section x ₂ with x ₂ = x - xi.

Back-up roll (100) according to claim 7 or 8,

characterized in that the ratio of the fifth radius to the fourth radius is about 6.66.

0. support roller (100) according to any one of the preceding claims,

characterized,

that the groove is formed in the transition region between the roll neck and the end face of the roll bale. Roller arrangement with

a back-up roll (100) according to any one of the preceding claims; and two bearings (300-1) in which the support roller (100) with its roll neck (1 14-1, 1 14-2) is mounted, wherein the two bearings (300-1) are each formed as a sliding bearing or as a rolling bearing.