Cross edge rolling

Abstract

The invention relates to a cross edge rolling process for increasing a thickness of a strip (1) in longitudinal edge strips (6) on both longitudinal sides of the strip (1). According to the invention, this is achieved in that first a step (11) running in the longitudinal direction of the strip (1) is produced by means of a roll profiling process, wherein the strip (1) is supported on said step against an edging force acting transversely to the strip (1) during the cross edge rolling process such that the strip (1) is not edged outside of the longitudinal edge strips (6). After the edging process for increasing the thickness of the longitudinal edge strips (6), the strip (1) is bent by means of a roll profiling process in order to form a C-profiled rail.

Description

[0001] The invention relates to a method for thickening a longitudinal edge strip of a strip by transverse edging rolling with the features of the preamble of claim 1.

[0002] A "band" is understood here to mean a strip of any length, preferably with a constant and flat, particularly rectangular, cross-section, which is in particular at least 5 times and preferably at least 10 times as wide as it is thick, with a thickness of the band being a smaller dimension and a width being a larger dimension of the band transverse to its length. The band consists of a plastically deformable material, particularly metal. Elastic deformability of the band is not desirable per se, but is also not excluded and is usually present in reality.

[0003] "Rolling" is the compression forming of the strip in a single pass between several rolls. "Cross-edging" refers to a process in which the strip is compressed in its transverse direction, i.e., narrowed, while a longitudinal edge strip of the strip becomes thicker. A "longitudinal edge strip" is a section running in the longitudinal direction of the strip, preferably of constant width, at one longitudinal edge of the strip. The strip can be cold-rolled or hot-rolled.

[0004] Patent EP 2 313 216 B1 discloses a transverse edging process for a metal strip, in which, in several successive steps, longitudinal edge strips along two longitudinal edges of the metal strip are formed and thickened into strips with a triangular cross-section, which are then bent at right angles to the same side of the metal strip by roll forming. For transverse edging, the strip is passed between an upper roll and a lower roll, with edging rolls on both longitudinal edges compressing the metal strip in its transverse direction, making it narrower and the two longitudinal edge strips thicker and triangular in cross-section. The lower roll is narrower than the metal strip, and the upper roll is as wide as the metal strip at the end of the transverse edging process.The top roll has chamfers, i.e., circumferential, inclined, or frustoconical surfaces at the transitions from the periphery to the end faces of the top roll, against which the edging rolls press the longitudinal edge strips of the metal strip. The edging rolls are disc-shaped and have circumferential annular steps with a circumferential groove on an inner edge, which press the metal strip against the top roll and compress it in the transverse direction. The two edging rolls are arranged at angles between 92° and 100° to the axes of the top roll and the bottom roll.

[0005] The object of the invention is to propose a method that exclusively, or at least predominantly, compresses and thickens a longitudinal edge strip of a strip transversely. Outside the longitudinal edge strip, the strip itself should not be deformed, although the invention does not exclude deformation of the strip outside the longitudinal edge strip.

[0006] This object is achieved according to the invention by the features of claim 1. Before or simultaneously with the transverse upsetting rolling, the strip is bent in opposite directions along two parallel bending lines running in a longitudinal direction of the strip, so that a step is formed running in a longitudinal direction of the strip, i.e., parallel to the longitudinal edge, which separates a longitudinal edge strip of the strip, which is to be upset transversely to the strip by rolling, from a remaining part of the strip. The transverse upsetting direction, in which the transverse upsetting rolling takes place, runs in particular at an angle of 45° to 135°, in particular of 70° to 110°, and preferably perpendicular to a longitudinal center plane of the strip, which is perpendicular to the transverse direction and is in particular a plane of symmetry. "Transverse direction" is understood here to mean the direction parallel to the transverse extent of the strip.The transverse compression direction is therefore preferably parallel to the transverse direction, but can also be slightly inclined to it. In particular, the transverse compression direction can vary during the transverse compression process, for example, it can be slightly inclined in a first step and parallel to the transverse direction in a second step.

[0007] The step, which can also be understood as a bend, serves to support the strip or the longitudinal edge strip in the transverse direction against a compression force which acts on the strip or the longitudinal edge strip transversely to the strip during simultaneous or subsequent transverse compression rolling, whereby it is possible to compress exclusively or at least essentially only the longitudinal edge strip of the strip between the longitudinal edge of the strip and the step running parallel to the longitudinal edge transversely to the strip and not to deform the rest of the strip, i.e. on a side of the step previously produced by bending facing away from the longitudinal edge, whereby the invention does not necessarily rule out deformation of the strip outside the longitudinal edge strip. Bending of the strip along more than two bending lines before or simultaneously with the transverse compression rolling is possible.

[0008] Preferably, the transverse upsetting rolling process is carried out in such a way that the longitudinal edge strip thickens from the bending line second closest to the longitudinal edge to the longitudinal edge. This does not preclude at least a minimal increase in thickness beyond this point. With two bending lines, the increase in thickness occurs at least from the longitudinal edge to the inner bending line. In other words, the transverse upsetting rolling process extends into the region of the step. However, thanks to the support according to the invention, at least no significant deformation occurs beyond the step toward the center of the strip. The step running in the longitudinal direction, i.e., parallel to the longitudinal edge of the strip, is bent, in particular, by roll forming, which is also referred to as "roll forming."

[0009] One embodiment of the invention provides that the strip is upset rolled in the transverse direction by an upsetting roller arranged laterally of the strip, which presses against the longitudinal edge of the strip and is supported by a support roller on the step which is bent at the same time or previously and runs parallel to the longitudinal edge of the strip against the upsetting force exerted by the upsetting roller on the longitudinal edge transversely to the strip, so that only or essentially only the longitudinal edge strip between the step and the longitudinal edge of the strip is subjected to the upsetting force and is upset transversely to the strip, whereby the longitudinal edge strip thickens.

[0010] In one embodiment of the invention, the support roll is arranged on a side, referred to here as the "top side," extending from one longitudinal edge to an opposite longitudinal edge of the strip. The term "top side" refers to the side toward which the step is raised. The top side does not necessarily have to be "on top" during rolling. During cross-edging rolling, an end face of the support roll supports the strip at the step running parallel to the longitudinal edge against the upsetting force of the upsetting roll pressing against the longitudinal edge of the strip. The "end face" is understood here to mean a surface that is not parallel to the axis of rotation.

[0011] Preferably, longitudinal edge strips are cross-compressed along both longitudinal edges of the strip. For this purpose, steps running parallel to the longitudinal edges are previously bent to support the compressive forces acting transversely to the strip. In particular, the strip is formed symmetrically to a longitudinal center plane.

[0012] A further development of the invention provides for the strip to be formed, after cross-edging, particularly by roll forming, into a C-profile rail, i.e., a type of rectangular tube with a continuous longitudinal slot in one side of the tube. Such C-profile rails are used as mounting rails for fastening to walls and ceilings.

[0013] In one embodiment of the invention, the strip is bent at the inner bending line, farthest from the longitudinal edge, between 45° and 90°, in particular between 50° and 80°. If there are more than two bending lines, the innermost bending line is meant.

[0014] In one embodiment of the invention, an end face of the support roller, which supports the strip at the step parallel to the longitudinal edge of the strip against the compression force of the compression roller acting transversely to the strip, has an angle between 45° and 90°, in particular between 50° and 80°, to a rotation axis of the support roller.

[0015] At an upsetting point, at which a circumferential upsetting surface of the upsetting roller presses against the longitudinal edge of the strip, the upsetting surface in one embodiment of the invention has an angle of between 70° and 85° to an axis of the support roller, so that the upsetting surface acts on the step running parallel to the longitudinal edge of the strip during upsetting against the end face of the support roller, which supports the step of the strip against the upsetting force of the upsetting roller acting transversely to the strip.

[0016] In particular, the axes of the support roller and the compression roller are at an angle of 70° to 90° and preferably perpendicular to each other.

[0017] One embodiment of the invention provides that the compression roll has a support surface, in particular in the form of an annular disc, which rests on the step of the strip and supports the step during transverse compression rolling against bending in the direction in which the step is raised relative to the remaining part of the strip.

[0018] Preferably, the step is bent using two bending lines, with the bending angles deviating by a maximum of 45°, in particular a maximum of 30°, and preferably a maximum of 20°. These are the bending angles achieved in the state in which the transverse upsetting roll is performed simultaneously or subsequently. The bending angles, which are equal or at least similar in magnitude, ensure that the step has an approximately parallel offset and the longitudinal edge is aligned transversely, so that the transverse upsetting roll can be performed transversely.

[0019] Preferably, the step has a height corresponding to 0.5 to 1.5 times the thickness of the band in the region of the step.

[0020] The invention is explained in more detail below with reference to the drawing. The figures show successive steps of the inventive method in a simplified and schematic representation.

[0021] They show: Figure 1 shows a strip in longitudinal view at a rolling station during a first step in the production of a step; Figure 2 shows the same strip during a second step in the production of the step; Figure 3 shows the same strip during a first step of cross-edging rolling; Figure 4 shows the same strip during a second step of cross-edging rolling; and Figure 5 shows the same strip bent into a C-profile rail.

[0022] In several steps, the volume 1 is converted into Figure 5shown C-profile rail 2 is produced, which has a rectangular tube cross-section with a continuous longitudinal slot 3 in the transverse center of one side. The figures show successive forming steps, whereby further forming steps (not shown) can take place between the forming steps shown in the figures or several forming steps can be combined. The figures show the forming on one long side of the strip 1, on an opposite long side the strip 1 is formed in the same way. The strip 1 is formed symmetrically to a plane of symmetry which is perpendicular to the originally flat cross-section of the strip 1 and runs in a transverse center of the strip 1 in its longitudinal direction, which plane is a longitudinal center plane LM. The strip 1 extends with its transverse extent in a transverse direction Q, to which the longitudinal center plane LM is perpendicular.

[0023] The strip 1 can basically be of any length; it can consist of long pieces several meters long or be unwound from a coil. In the exemplary embodiment, it has a flat rectangular cross-section with a thickness of between 1.5 millimeters and 2.5 millimeters and is between 30 and 60 times as wide as it is thick. The strip 1 is made of a plastically deformable material, in particular steel, an aluminum alloy, or metal in general. Elastic deformability of the strip 1 is rather undesirable because it can impair plastic deformation; however, elastic deformability of the strip 1 cannot be ruled out and is unavoidable, at least to a small extent, in practice.

[0024] In each forming step, the strip 1 is guided between an upper roller 4 and a lower roller 5, which roll on two opposite large sides of the strip 1. In the exemplary embodiment, the upper roller 4 and the lower roller 5 are cylindrical rollers with parallel axes, which have a gap equal to or slightly less than the thickness of the strip 1 in order to clamp the strip 1 between the upper roller 4 and the lower roller 5 and possibly also reduce the thickness of the strip 1. The upper roller 4 and the lower roller 5 do not have to be arranged horizontally or one above the other.

[0025] Longitudinal edge strips 6 on both long sides of the belt 1 are cut in the run as in Figure 1As can be seen, with first bending rollers 7 arranged laterally of the upper roller 4 and the lower roller 5 on each side of a first or inner bending line 8, which runs parallel to the longitudinal edges 9 of the strip 1, bent in the same direction. The longitudinal edge strips 6 are bent by up to 90°. In the exemplary embodiment, the longitudinal edge strips 6 of the strip 1 are bent in several stages, of which Figure 1 a final stage, is bent by a total of approximately 70° to 80°. The first bending rollers 7 are also cylindrical rollers or truncated cone-shaped rollers, whose axes are in the same plane as the axes of the upper roller 4 and the lower roller 5. The invention does not exclude rollers other than bending rollers 7.

[0026] Subsequently, the longitudinal edge strips 6 on both sides of the strip 1 are bent along second or outer bending lines 10 in an opposite direction to the previous one. The bending lines 8, 10 are shown in the figure by dashed lines, which themselves are not parallel to the longitudinal edges 9, but rather correspond to the bisector of the bending angle. This means that the bending lines 8, 10 run perpendicular to the dashed lines and perpendicular to the plane of the illustration. The outer bending lines 10 run parallel to the inner bending lines 8 and parallel to the longitudinal edges 9 of the strip 1 at a distance of approximately the thickness of the strip 1 outside the inner bending lines 8, i.e. the outer bending lines 10 are closer to the longitudinal edges 9 than the inner bending lines 8. The bending of the longitudinal edge strips 6 along the outer bending lines 10 in the opposite direction to the previous one is preferably also carried out in several steps, of which Figure 2shows a final step until the longitudinal edge strips 6 run between the outer bending lines 10 and the longitudinal edges 9 parallel or at an acute angle of approximately 10° to 20° in the exemplary embodiment to the strip 1 between the inner bending lines 8. In the exemplary embodiment, the longitudinal edge strips 6 are bent back less far at the outer bending lines 10 than they are bent at the inner bending lines 8, so that the longitudinal edge strips 6 run obliquely in the direction in which they are also bent at the inner bending lines 8.

[0027] The double bending at the two bending lines 8, 10 in opposite directions creates a step 11 that extends in the longitudinal direction of the strip 1 parallel to the longitudinal edges 9 of the strip 1. Due to the bending of the strip 1 at the inner bending lines 8 by - in the exemplary embodiment - approximately 70° to 80°, a section of the strip 1 between the inner and outer bending lines 8, 10 has an angle of approximately 100° to 110° to the middle section of the strip 1 between the inner bending lines 8. In other words, the magnitude of the bending angles at the two bending lines 8, 10 deviates by approximately 10° to 20°. As a result, the step 11 has an approximate parallel offset. A height H of the step 11 corresponds approximately to the thickness D of the strip 1 in the area of ​​the step 11.

[0028] For bending along the outer bending lines 10, the longitudinal edge strips 6 in the exemplary embodiment are passed between two second bending rollers 12, which rest on the top and bottom sides of the strip 1 in the longitudinal edge strips 6. The second bending rollers 12 are also cylindrical or frustoconical rollers, the axes of which are located in a plane perpendicular to the passage plane of the strip 1 with the axes of the upper roller 4 and the lower roller 5.

[0029] The bending of the strip 1 at the bending lines 8, 10 is a roll forming process, which is also called roll forming.

[0030] Instead of the separate first and second bending rollers 7, 12, the double bend can also be achieved by appropriately shaped upper and lower rollers (not shown), which extend into the area of ​​the longitudinal edge strip 6 and have a stepped shape corresponding to the step 11. In this way, the two bending lines 8, 10 can be produced simultaneously, in particular, although this can again be distributed over several forming steps with successively arranged upper and lower rollers. Preferably, however, the double bend, i.e., the creation of step 11, takes place in a single step.

[0031] After bending the strip 1 along the inner bending lines 8 in one direction and along the outer bending lines 10 in the opposite direction, the strip 1 is upset rolled in a transverse upset direction QS using laterally arranged upset rollers 13 that press against the longitudinal edges 9 of the strip 1 transversely. The axes of the upset rollers 13 are perpendicular to the axis of the top roll 4. Alternatively, the transverse upset rolling can also take place simultaneously with the bending of step 11, particularly if step 11 is created by appropriately shaped top and bottom rolls (not shown). In this case, an upset roller protrudes between the top and bottom rolls. For clarity, however, the transverse upset rolling is shown here as a separate, subsequent step.The compression rollers 13 have a frustoconical or cylindrical compression section 14 that rolls on the longitudinal edges 9 of the strip 1, and a disk-shaped support section 15 that rests on the upper side of the longitudinal edge strips 6 of the strip 1. The upper side is the side to which the longitudinal edge strips 6 are offset by the double bending in opposite directions relative to the central section of the strip 1 between the inner bending lines 8, i.e., towards which the steps 11 are raised. The support sections 15 of the compression rollers 13 prevent the longitudinal edge strips 6 from being bent back in the opposite direction to that previously during bending when the strip 1 is compressed in the transverse direction Q. Perforated disk-shaped surfaces of the support sections 15 that rest on the longitudinal edge strips 6 can also be regarded as support surfaces 16.Deviating from the embodiment, separate support rollers or fixed support surfaces can be provided for the compression rollers 13 (not shown).

[0032] During transverse upset rolling, the steps 11 of the strip 1 rest on its upper side between the inner and outer bending lines 8, 10 against end faces 17 of the top roll 4, which forms a support roll 18 that supports the strip 1 or the longitudinal edge strips 6 of the strip 1 at the step 11, i.e. in the section running in the longitudinal direction of the strip 1 between the inner and outer bending lines 8, 10 in the transverse direction Q of the strip 1, against an upset force that the upset rolls 13 exert transversely to the strip 1 on the longitudinal edges 9 of the strip 1. Due to the support at the step 11, only the longitudinal edge strips 6 of the strip 1 are upset rolled, whereby they become thicker and narrower in the transverse direction Q of the strip 1. The end faces 17 of the upper roller 4 forming the support roller 18 can be flat radial surfaces or conical or frustoconical, i.e. they have an angle between 45° and 90° to a circumferential surface of the support roller 18.

[0033] A circumferential surface of the frustoconical compression section 14 of the compression rollers 13 has an angle of between approximately 85° and 70° to the axis of the support roller 18 at a compression point ( Figure 3 ). The circumferential surface of the upsetting section 14 of the upsetting rollers 13 can also be regarded as the upsetting surface 19. The upsetting point is the point at which the upsetting surface 19 or the upsetting rollers 13 rest against the longitudinal edge 9 of the strip 1 during upsetting. The transverse upsetting direction QS, in which upsetting occurs during the first step of the transverse upsetting rolling process, therefore does not run entirely perpendicular to the longitudinal center plane LM.

[0034] In the last compression step, the Figure 4shows, the bottom roller 5 is so wide that the strip 1 including its longitudinal edge strips 6 rests on it. This results in a flat large side of the strip 1, which in the exemplary embodiment has a manufacturing-related groove running in the longitudinal direction of the strip 1 with a rounded cross-section in the area of ​​the bending lines 8, 10. The flat large side of the strip 1 after the cross-edging rolling forms Figure 5 C-profile rail 2 shown has an outer side. Figure 4 In the illustrated step of the transverse upsetting rolling, the transverse upsetting direction QS is perpendicular to the longitudinal center plane LM, since the upsetting surface 19 is cylindrical here. As can be seen in Figure 4 As can be seen, the longitudinal edge strip 6 becomes thicker up to the inner bending line 8 and even slightly beyond. The transverse upsetting rolling thus extends into the area of ​​stage 11.

[0035] The Figures 3 and 4show a first and a second cross-edging rolling step, whereby the longitudinal edge strips 6 can be cross-edged in further steps not shown, so that the deformation in the individual steps is smaller. The strip 1 can be cold or hot-edged.

[0036] After the transverse upsetting rolling of the longitudinal edge strips 6 of the strip 1, the strip 1 is rolled in several steps (not shown) to the Figure 5 The C-profile rail 2 shown is bent. The bending is carried out in a continuous process by roll forming, as in step 11. List of reference symbols

[0037] 1Strip 2C-profile rail 3Longitudinal slot 4Top roller 5Bottom roller 6Longitudinal edge strip 7First bending roller 8Inner bending line 9Longitudinal edge 10Outer bending line 11Step 12Second bending roller 13Upsetting roller 14Upsetting section 15Support section 16Support surface 17End surface 18Support roller 19Upsetting surface DDickness of strip 1 in the area of ​​step 11 HHeight of step 11 LMLongitudinal center plane QTransverse direction QSTransverse compression direction

Claims

1. Method for thickening a longitudinal edge strip (6) of a strip (1) made of a plastically deformable material, wherein the strip (1) is transversely compression-rolled in its transverse direction (Q) so that the strip (1) becomes narrower and at the same time the longitudinal edge strip (6) becomes thicker, characterized in that before or simultaneously with the cross edge rolling process, the strip (1) is bent in a transverse direction (QS) in opposite directions along two parallel bending lines (8, 10) which extend in a longitudinal direction of the strip (1) and otherwise delimit the longitudinal edge strip (6) from the strip (1), so that a step (11) extending in the longitudinal direction of the strip (1) is produced, on which step the strip (1) is supported transversely to the strip (1) during the cross edge rolling process of the longitudinal edge strip (6).

2. Method according to Claim 1, characterized in that the strip (1) is bent at the bending lines (8, 10) by means of a roll profiling process.

3. Method according to Claims 1 or 2, characterized in that the cross edge rolling process is designed in such a way that the strip (1) is compression-rolled in the transverse compression direction (QS) by an edging roller (13), which is arranged laterally in relation to the strip (1) and presses against a longitudinal edge (9) of the strip (1), and in the process is supported by a support roller (18) on the previously or simultaneously bent step (11) extending parallel to the longitudinal edge (9) of the strip (1), in the transverse direction (Q) of the strip (1) against a compression force of the edging roller (13).

4. Method according to Claim 3, characterized in that a support roller (18) is arranged on an upper side of the strip (1) and in that an end face (17) of the support roller (18) supports the strip (1) against the compression force of the edging roller (13) on the step (11) extending in the longitudinal direction of the strip (1).

5. Method according to one or more of the preceding claims, characterized in that the strip (1) is bent and transversely compression-rolled on both longitudinal edges (9) at two bending lines (8, 10) parallel to the longitudinal edges (9), preferably identically on both longitudinal edges (9), to form a profile symmetrical in relation to a longitudinal center plane (LM) perpendicular to the transverse direction (Q) of the strip (1).

6. Method according to one or more of the preceding claims, characterized in that the strip (1) is bent after the cross edge rolling process to form a C-profile rail (2).

7. Method according to one or more of the preceding claims, characterized in that the strip (1) is bent between 45° and 90°, in particular between 50° and 80°, at the inner bending line (8) remote from the longitudinal edge (9).

8. Method according to Claim 4, characterized in that the end face (17) of the support roller (18) is at an angle between 45° and 90°, in particular between 50° and 80°, to a circumferential surface of the support roller (18).

9. Method according to one or more of Claims 3 to 8, characterized in that at a compression point pressing against the longitudinal edge (9) of the strip (1), a circumferential compression surface (19) of the edging roller (13) is at an angle between 70° and 85° to an axis of rotation of the support roller (18).

10. Method according to one or more of Claims 3 to 9, characterized in that the edging roller (13) has a support surface (16) which rests on the longitudinal edge strip (6) of the strip (1).

11. Method according to one or more of the preceding claims, characterized in that the bending process of the step (11) takes place with two bending lines (7, 8) and in that the size of the bending angles differs at most by 45°, in particular at most by 30°, and preferably at most by 20°.

12. Method according to one or more of the preceding claims, characterized in that the step (11) has a height (H) which corresponds to 0.5 to 1.5 times the thickness (D) of the strip (1) in the region of the step (11).

13. Method according to one or more of the preceding claims, characterized in that the cross edge rolling process takes place in such a way that the longitudinal edge strip (6) becomes thicker from the second-closest bending line (8) to the longitudinal edge (9) up to the longitudinal edge (9).

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