The invention relates to the field of flattening thick metal strips or plates. It relates in particular to a device for turning over a flattening element and a flattening element engaging with the device.
Thick strips are flattened by a succession of alternating flexions of decreasing amplitude without any application of external traction upstream or downstream of the flattening machine. These flattening machines comprise two flattening elements each carrying a series of cylinders with parallel axes placed respectively above and below the strip, the cylinders being offset longitudinally and vertically so as to be nested, thus determining an undulating path for the strip, which is thereby subjected to the effects of successive alternating flexions. These alternating flexions are reflected in curves generating deformations in the strip which vary from a state of traction on the upper surface of the curve to a state of compression on the lower surface, passing through a zero value in the median axis or “neutral fiber” of the strip according to a law of linear variation. Depending on the amplitude of the curve, the stresses thus generated may exceed the elastic limit of the strip over a greater or lesser fraction of its thickness. This plasticization is a decisive element in the elimination of evenness defects which cannot be drawn out, such as “long edges”, “long centers”, etc. The plasticized fraction of the thickness of a strip is usually expressed as a percentage of the total thickness designated by the term “plasticization rate”.
Generally speaking, each flattening element, respectively lower or upper, comprises a plurality of cylinders with parallel axes which normally have a reduced diameter and are therefore held by at least two supporting cylinders, which may themselves rest on rows of wheels, the set of these cylinders and wheels being assembled on a frame.
These two flattening elements, placed respectively below and above a horizontal plane of travel of the strip, are placed in a supporting frame comprising four columns arranged on each side of the longitudinal axis of travel of the strip and firmly held in their lower part by a fixed base and in their upper part by transverse beams, the assembly forming a closed frame.
The lower flattening element rests on the fixed base and the upper element rests on a pressure frame which can be moved vertically between the four columns by means of mechanical or hydraulic jacks resting on the upper part of the frame so as to adjust the separation of the two flattening elements and, consequently, the nesting of the cylinders, while taking up the separating forces due to the resistance of the product.
Usually, at least some of the flattening cylinders are rotated about their axes in order to advance the strip by friction at a determined speed following an undulating path between the lower and upper cylinders.
During the flattening operation, the cylinders are subjected to high surface pressure stresses and abrasion phenomena, which require reconditioning, for example machining by grinding their active surfaces, in a maintenance workshop. In this context, the upper and lower flattening elements must be removed from the flattening machine. The lower flattening element with its flattening cylinders directed upward will easily be able to be ground. However, the upper flattening element with its flattening cylinders directed downward must first of all be turned over so that the operators can gain access to its flattening cylinders.
Publication WO2008/099126 discloses a turning-over device for an upper flattening element of a flattening machine. The flattening element is first extracted from the flattening machine and held by a lifting beam. The lifting beam is then placed on a cradle. During all these stages, the cylinders of the upper flattening element are not accessible to the operators and the actual repair operations cannot begin. The lifting beam is rotatably mounted on a cradle about pivots and is able to pivot about a horizontal axis so as to rotate the upper flattening element. It is only at the end of this last stage that the flattening cylinders of the upper flattening element become accessible.
These turning-over operations require the execution of numerous operations implemented by operators in a potentially dangerous environment. The operators must in particular maneuver the lifting beam and the supporting cradle for the flattening cylinders, which may be at high temperatures. Also, a large number of successive manipulations and operations have to be undertaken.
There is therefore a need for a simple means of turning over, necessitating the least possible operator intervention and performing the fastest possible turning over with the fewest stages possible.
For this purpose, the object of the invention is a turning-over device for a flattening element, the flattening element comprising a plurality of cylinders spaced apart from each other and rotatably mounted on a frame and means for securing it to the turning-over device, the turning-over device being characterized in that it comprises:
According to other characteristics of the turning-over device:
The object of the invention is also a flattening element suitable for engaging with the turning-over device as defined above, the flattening element comprising a plurality of cylinders spaced apart from each other and rotatably mounted on a frame characterized in that it comprises means for securing same to the turning-over device.
According to other characteristics of the flattening element:
Other characteristics and advantages of the present invention will become apparent upon reading a detailed, non-restrictive embodiment, with reference to the figures where:
For this purpose, the upper flattening element 20 comprises means for securing it to the turning-over device 10. More precisely, the securing means of the flattening element 20 comprise a plurality of hooks 22 integrated with the frame 44 and intended to engage with the securing means 40 of the turning-over device. As can be seen in
Each hook 22 of the flattening element is positioned so as to rest on one of the hooks 40 of the turning-over device 10 when the flattening element is completely inserted into the turning-over device 10, as will be explained later. The hooks 22 define a passage for the hooks 40 of the turning-over device, these latter also acting as guides for the upper flattening element during its introduction into the turning-over device 10. The hooks 22 are grouped in pairs, each pair of hooks 22 being approximately at the top of an imaginary rectangle of predetermined length and width. The hooks 22 of a single pair extend parallel to each other from a vertical face of the frame 44 of the upper flattening element 20.
The assembly formed by the two flattening elements is placed on a transfer platform 50, itself placed on transport rails 52. This platform 50 is connected to a transfer jack 54 capable of pushing the platform 50 from a position in which the assembly formed by the two flattening elements 20 and 46 is located outside the turning-over device to a position in which the upper flattening element 20 is held by the turning-over device 10, as will be explained later.
As can be seen in
The uprights 14 are installed opposite each other and are separated by a distance allowing for the insertion of an assembly of flattening elements 20, 46. Each supporting upright 14 comprises two arms 24 arranged opposite each other and extending vertically from the base 14. Each arm 24 comprises triangular fins 24A extending vertically from the base 14 and integrated with a straight vertical portion 24B. Each arm 24 also comprises, on the internal face of each straight portion 24B, at least one guide rail 26 for the vertical translation means 18 of the supporting and securing means 16.
According to the invention, the vertical translation means 18 of the supporting and securing means 16 and thus of the upper flattening element 20 comprise translation drive spindles 38 each extending vertically and parallel between the two arms 24 of each upright 12. Preferably, two cylindrical translation drive spindles 38 are installed per upright. The translation drive means also comprise two guide rods 18 each accepting two of the translation drive spindles 38 to drive then in vertical translation, each guide rod 18 being suitable for ascending or descending along the drive spindles 38 it accepts under the action of a drive device which may be internal to each guide rod 18. The translation drive spindles 38 may form part of screw jacks. Each guide rod is positioned between the arms 24 of an upright 12 and is guided in translation by two rails 26. The vertical translation means 18 may comprise other types of drive device, such as other types of jacks, screw/nut or pinion/rack systems or even chains.
The turning-over device 10 of the upper flattening element 20 comprises supporting and securing means comprising a frame 16. The frame 16 comprises two horizontal crosspieces 28 extending longitudinally and parallel between the uprights 12. The crosspieces are connected together by two transverse bars 30. The crosspieces 28 and the transverse bars 30 extend in a plane perpendicular to the planes containing the uprights 12. The length of each transverse bar is greater than the length of the assembly formed by the upper 20 and lower 46 flattening elements.
The frame 16 also comprises two holding pieces 32 placed opposite each other which each accept one of the ends of each crosspiece 28 and these holding pieces 32 are also integrated with the translation drive means 18 of the supporting and securing means 16. More precisely, in the embodiment represented in
The supporting and securing means 16 comprise a plurality of hooks 40 each extending from one of the holding pieces 32 below a crosspiece 28, the free end 41 of each hook 40 being directed upward when the turning-over device 10 is in its first position. Each hook 40 is positioned so that the distance between its free end 41 and the lower face of the horizontal crosspiece 28 closest to it allows the passage of the securing means 22 belonging to the flattening element 20 and clamping of this flattening element 20.
Also, each hook 40 comprises at its free end a cylindrical portion 41 intended to support and guide the securing means 22 of the flattening element 20 when it is introduced into the turning-over device 10. In the embodiment in
The supporting and securing means 16 comprise retaining means for stopping the translation of the flattening element 20 and for holding the flattening element 20 during rotation of the supporting and securing means 16. The retaining means comprise two L-shaped clamping bars 36 forming a stop for the flattening element 20 during rotation of the supporting and securing means 16. Each clamping bar 36 is integrated with a transverse bar 30 and extends downward from this transverse bar 30 when the turning-over device 10 is in its first position.
According to the invention, the turning-over device also comprises rotary drive means 19 for the supporting and securing means. These rotary drive means 19 are, in the embodiment in
In order to allow for interlocking of each hook 22 of the upper flattening element 20 with a corresponding hook of the turning-over device 10, the width of the imaginary rectangle defining the position of the hooks 22 of the flattening element 20 may be less than or equal to the width of the imaginary rectangle defining the position of the hooks 40 of the turning-over device 10.
A description will now be given of the different stages of turning over a flattening element 20 with reference to
During a first stage, the vertical translation drive means of the guide rods 18 are actuated to drive the guide rods 18 and thus the frame 16 until the hooks 40 of the frame 16 are positioned opposite the hooks 22 of the upper flattening element 20 closest to the turning-over device 10. The jack 54 then pushes the platform 50, which gives rise to the translation of the assembly comprising the upper 20 and lower 46 flattening elements. During this translation, the first two pairs of hooks 22 of the upper flattening element 20 closest to the turning-over device 10 each engage on the cylindrical portion 41 of one of the first hooks 40 belonging to the frame 16. Each cylindrical portion 41 of a first hook 40 belonging to the frame 16 thus acts as a translation guide for the assembly formed by the two upper 20 and lower 46 flattening elements. Translation proceeds and the first pairs of hooks 22 of the upper flattening element 20 advance and go past the first hooks 40 belonging to the frame 16. Each first pair of hooks 22 of the upper flattening element 20 then engages on the cylindrical portion 41 of one of the second hooks 40 belonging to the frame 16, the second hooks 40 (visible in
The vertical translation drive means for the guide rods 18 are then actuated to drive the guide rods 18 and thus the frame 16 upward. The upper flattening element 20 engaged with the frame 26 is also driven upward and is detached from the lower flattening element 46. We are then in the position represented in
The transfer jack 54 then pulls the platform 50 toward another zone of the flattening installation for the lower flattening element 46 to be ground.
In the following stage, the vertical translation drive means 38 for the guide rods 18 are actuated to drive the guide rods 18 and thus the frame 16 in vertical translation downward. We are then in the position represented in
Next, the drive means 19 for rotating the frame about a horizontal axis are actuated. The upper flattening element 20 pivots through 180 degrees in the clockwise direction from a first position in which the cylinders 43 of the upper flattening element 20 are directed downward to a second position in which the cylinders 43 of the flattening element 20 are oriented upward. An intermediate position of the flattening element pivoted through 90 degrees is represented in
In the following stage, the vertical translation drive means for the guide rods 18 are actuated to drive the guide rods 18 and thus the frame in vertical translation downward to a low position allowing an operator to gain access to the flattening cylinders of the upper flattening element 20 or allowing it to be gripped by a handling tool with a view to removal to another zone of the installation.
Number | Date | Country | Kind |
---|---|---|---|
09 290 208 | Mar 2009 | EP | regional |
Filing Document | Filing Date | Country | Kind | 371c Date |
---|---|---|---|---|
PCT/EP2009/054764 | 4/22/2009 | WO | 00 | 11/8/2011 |