MULTI-FUNCTIONAL ROLLING STAND AND RELATIVE METHOD OF USE

Description

FIELD OF THE INVENTION

[0001] The present invention concerns a multi-functional rolling stand which is able to perform at least some of the functions of a forging press, and also the relative method of use, see for example US-A 3217520.

BACKGROUND OF THE INVENTION

[0002] It is known that, in order to work large-size ingots or blooms, nowadays forging presses are also and mainly used.

[0003] Forging presses of the known type, however, have several limitations and rather long working times; moreover they require careful control in every specific working step of forging.

[0004] Furthermore, forging presses sometimes require that the piece being worked is re-heated, so that it is possible to continue forging efficiently.

[0005] All this causes considerable disadvantages in terms of plant productivity, times for transferring the products, the need for manpower and other disadvantages.

[0006] One purpose of the present invention is to achieve a rolling stand that allows to overcome the limitations of forging presses in order to achieve, starting from large-size ingots or plates, products with a round, square or rectangular section, in a short time and simply.

[0007] Another purpose of the present invention is to achieve a rolling stand that allows to work blooms or round pieces having a maximum transverse size up to a value that goes from about 1250mm to about 1450mm, and plates having a maximum width up to a value that goes from about 1400mm to about 1500mm and having a maximum thickness from about 400mm to about 500mm.

[0008] A rolling stand that therefore allows extremely high compression forces, for example so as to work ingots in the same way as a forge, as described in more detail hereafter, and having these operating potentialities, has never before been hypothesized or described. In order to achieve it, Proprietor has had to overcome the classical and widespread norms, by means of a specific study and related experimentation, obtaining a rolling stand that also transcends the classical norms relating to two-high roughing stands.

[0009] The Applicant has devised, tested and embodied the present invention to overcome the shortcomings of the state of the art and to obtain these and other purposes and advantages.

SUMMARY OF THE INVENTION

[0010] The present invention is set forth and characterized in the independent claims, while the dependent claims describe other characteristics of the invention or variants to the main inventive idea.

[0011] In accordance with the above purposes, a rolling stand according to the present invention is suitable for working large plates, large blooms, large round pieces and other large-size semi-worked products, for example large tonnage ingots, 25-30 tonnes, with a diameter of up to 1400mm, or similar products.

[0012] According to a characteristic feature of the present invention, the rolling stand comprises rolls having a diameter comprised between 1600mm and 2000mm, advantageously about 1800mm. According to the present invention, the linear dimensions of the table of the rolls are comprised between about 3500mm and about 4500mm, advantageously around 4000mm.

[0013] According to a variant, the table of the rolls has a flat central zone with a width comprised between 1500mm and 2500mm, advantageously about 2000mm, and at least a lateral zone, advantageously two lateral zones, with a width comprised between about 900mm and about 1000mm, which have suitable channels or grooves.

[0014] The channels can advantageously be used for working sidewise, or edgewise, the wide plate after rolling on the main dimension, or for working round pieces in the case of products starting from a bar shape.

[0015] According to one solution, the channels have a depth comprised between about 60mm and about 100mm, advantageously between about 80mm and about 90mm, while their width varies from about 80mm to about 400mm.

[0016] According to a variant of the present invention, the rolling stand comprises positioning bolts able to act on the chocks of the rolls to position them quickly in the desired position between one pass and the next of the product being worked. The bolts are provided with a trapezoid threading having a pitch of about 44mm in order to have the desired degree of accuracy in the positioning.

[0017] In particular, the two rolling rolls can assume a work position close up to or substantially close up to each other, and can move away from each other as far as a maximum travel or gap comprised between 1300mm and 1500mm, advantageously around 1400mm.

[0018] The distanced position can be assumed both during the sidewise or edgewise rolling of a bloom or wide plate, after it has been turned over on one side, and also for working an ingot for example of a size of around 1400mm.

[0019] The high compression force, in particular in the case of ingots, also causes the elimination or great reduction of the internal porosities that are typically present in the ingots.

[0020] Another variant of the present invention provides a speed of positioning the chocks of the rolls that goes from about 60 mm/s to about 90 mm/s, advantageously about 75 mm/s.

[0021] According to a variant of the present invention, the entrance angle, or rather half-angle, has a maximum value of around 20° per roll.

[0022] According to a variant of the present invention one rollerway is provided upstream and one rollerway downstream of the rolling stand.

[0023] Another variant provides that the rolling stand is reversing so that it can work with the product advancing in both directions of feed.

[0024] According to a variant of the present invention the maximum rolling speed is comprised between 80 m/min and 130 m/min, advantageously around 100 m/min.

[0025] The minimum rolling speed is comprised between 0.1 m/min and 1 m/min.

[0026] A variant of the present invention provides a motor to drive the rolling stand having a power comprised between 7000 Kw and 14,000 Kw. If a motor is used having a power of about 8000 Kw, the torque will be around 3000 KNm.

[0027] The compression force can reach up to about 6000 tonnes in the case of ingots, depending on the type of product being worked and on the reduction ratio to be obtained. Thanks to these high forces in play, which allow to obtain compressions comprised between 100 and 150 mm, the rolling stand according to the present invention is similar to a forge so that, as we said, the internal porosities of the product are eliminated.

[0028] According to a variant of the invention, upstream and/or downstream of the rolling rolls there is at least a tilter device to dispose the plate on one side, so as then to be able to perform the rolling pass sidewise or edgewise, or edge-refining, in the same rolling stand using a suitable channel of the lateral zones. In this way it is not necessary to provide suitable vertical edge-refining rolls upstream or downstream of the stand.

[0029] Another variant of the present invention provides a thruster element at least on a front side of the rolling stand.

BRIEF DESCRIPTION OF THE DRAWINGS

[0030] These and other characteristics of the present invention will become apparent from the following description of a preferential form of embodiment, given as a non-restrictive example with reference to the attached drawings wherein:

• fig. 1 is a lateral and schematic view of the rolling stand according to the present invention;
• fig. 2a is a view of a possible embodiment of a sheet-turner;
• fig. 2b is a view of a possible embodiment of an ingot-turner;
• figs. 3a, 3b and 3c show examples of use of the channels disposed on the sides of the flat part of the rolling roll.

DETAILED DESCRIPTION OF A PREFERENTIAL FORM OF EMBODIMENT

[0031] With reference to fig. 1, a multi-functional rolling stand 10 according to the present invention comprises a shoulder 11, disposed on a base 20, in which two rolling rolls are mounted, respectively lower 12a and upper 12b.

[0032] The rolling stand 10 can perform rolling, forging and/or finishing functions for large size rolled products 13, for example wide plates, blooms, ingots, large size round pieces and others, having a maximum transverse size up to around 1500mm and, in the case of plates, a maximum thickness of up to 500mm.

[0033] The compression force can reach up to about 6000 tonnes, and allows to obtain compressions comprised between 100 and 150 mm, depending on the type of product 13 being worked and the reduction ratio to be obtained, in particular in the case of ingots so as to obtain a better internal quality of the product emerging from the compression pass.

[0034] The rolls 12a and 12b are associated in a known manner with supporting chocks which allow a reciprocal displacement thereof, by means of suitable positioning bolts, between a close up or substantially close up position and a substantially distanced position.

[0035] Fig. 1 shows the close up position of the upper roll 12b, indicated by a line of dashes, which defines the minimum gap in the rolling pass of the product to be rolled/forged 13, whereas the distanced position defines the maximum value of the gap "I" that can reach up to 1400mm.

[0036] The gap defines the maximum size of an ingot that can be worked between said rolls 12a, 12b and/or the size of the wide plate after it has been tilted over onto its side so as to carry out the sidewise or edgewise working.

[0037] Upstream and downstream of the rolling rolls 12a, 12b there are rollerways 14 to transport the product which, since the rolling stand 10 is of the reversing type, perform the function, on different occasions, of feeding and also of discharging the product 13 to/from the rolls 12a, 12b.

[0038] According to the invention, the rolls 12a and 12b have a diameter "d" of around 1800mm and a table with an overall width of around 4000mm.

[0039] Figs. 3a, 3b and 3c show how the rolls 12a, 12b have a flat zone 15, substantially central, said table having a width advantageously around 2000mm for rolling/forging wide plates, blooms, ingots 13, or other similar large size products, on their main dimension.

[0040] At the sides of the flat zone 15 there are zones 16, having a width from about 900mm to about 1000mm, which have suitable channels or grooves or throats 17 that can serve (17a) either for sidewise or edgewise working of the wide plate 13 after rolling on the main dimension, or (17b, 17c) for working round pieces in the case of round pieces in the case of long starting products in the form of a bar.

[0041] According to one embodiment, said channels 17a, 17b, 17c have a depth comprised between about 60mm and about 100mm, advantageously between about 80mm and about 90mm, whereas the width varies from about 80mm to about 400mm.

[0042] Upstream and/or downstream of the rolling rolls 12a, 12b there is at least a tilter device, denoted in its entirety by the reference number 18 in fig. 2a, which is configured to dispose the plate 13 on one side, so that it can then perform the rolling pass edgewise in the same rolling stand.

[0043] In particular, the plate 13 is tilted over, according to the direction indicated by 30, until it assumes a substantially vertical position (shown by a line of dashes with 13a in fig. 2a), using a fork type device 19 able to be selectively driven by means of a jack 21 that acts on a lever 119 disposed on the rear of the fork 19.

[0044] The fork device 19 is mounted, in the solution shown here, on a positioning arm 22, governed by the drive of a jack 23, in turn mounted on a translation slider 24 movable by means of wheels 25.

[0045] The translation slider 24 allows to selectively insert the tilter device 18 in cooperation with the rollerways 14 that feed/discharge the product 13 associated with the rolling stand 10, in order to tilt the plate 13 onto one side. When the product 13 is in this substantially vertical position, it is held in position by means of containing and guide elements 32, so that it can be returned inside the rolling stand 10 between the rolls 12a, 12b, using the same rollerway 14.

[0046] The containing and guide elements 32 can move linearly in the direction 33 (fig. 2a), so as to support the product 13 in a vertical position and accompany it through the rolls 12a, 12b, disposed in a reciprocally distanced position (as indicated by a continuous line in fig. 1), and then grip the product 13 exiting from the rolls 12a, 12b after the edgewise working has been completed.

[0047] Fig. 2b shows schematically a tilter device for blooms or ingots 118, the function of which, substantially as shown above for the tilter device 18, is to tilt the bloom or ingot 13 along its longitudinal axis, when it is not gripped by the rolls 12a, 12b, in order to dispose it in a suitable position to perform the reduction in size on different generatrixes. When it has been tilted over, the bloom or ingot 13 is again returned between the rolls 12a and 12b in order to carry out said reduction in size. The tilter device 118 provides a fork 219, shorter in size than the fork 19 as described above, and able to be selectively driven by means of a jack 121 that acts on a lever 29 disposed on the rear of the fork 219 so as to lift the fork 219 in the direction indicated, and to determine the tilting over of the ingot 13.

[0048] Modifications or variants may be made to the present invention, which in any case come within the field of protection as defined by the attached claims.

Claims

1. Multifunctional rolling stand, suitable for rolling /forging large plates, large blooms, large round pieces and other large-size semi-worked products (13), for example ingots or similar products, characterized in that it comprises rolls (12a, 12b) having a diameter comprised between 1600mm and 2000mm, with a flat central zone (15) with sizes comprised between 1500mm and 2500mm, said rolls (12a, 12b) being able to be distanced from each other so as to define, in the distanced position, a working gap 1 comprised between 1300mm and 1500mm.

2. Rolling stand as in claim 1, characterized in that the linear sizes of the table of the rolls are comprised between about 3500mm and about 4500mm, advantageously around 4000mm.

3. Rolling stand as in claim 1 or 2, characterized in that, at the side of the flat central zone (15), there are work channels (17a, 17b, 17c) present, for at least working the edge of said large plates, large blooms, and other large-size semi-worked products (13).

4. Rolling stand as in claim 3, characterized in that each of the rolls (12a, 12b) comprises, on at least one side of the flat zone (15), lateral zones (16), with a width comprised between about 900mm and about 1000mm which include said channels (17a, 17b, 17c).

5. Rolling stand as in claim 4, characterized in that the channels (17a, 17b, 17c) have a depth comprised between about 60mm and about 100mm.

6. Rolling stand as in claim 4, characterized in that the width of the channels (17a, 17b, 17c) varies from about 80mm to about 400mm.

7. Rolling stand as in any claim hereinbefore, characterized in that it comprises, upstream and/or downstream of the rolling rolls (12a, 12b), at least a tilter device (18, 118) in order to dispose the large plate (13) on one side or to turn over the ingot (13) with respect to one edge thereof.

8. Rolling stand as in any claim hereinbefore, characterized in that the positioning speed of the chocks of the rolls (12a, 12b) during the steps of moving the rolls reciprocally closer to/away from each other is comprised between about 60mm/sec and about 90 mm/sec.

9. Rolling stand as in any claim hereinbefore, characterized in that it is of the reversing type.

10. Method for rolling /forging large plates, blooms, large round pieces and other large-size semi-worked products (13), for example ingots or similar products, in a rolling stand as in any claim hereinbefore, characterized in that it uses rolls (12a, 12b) having a diameter comprised between 1600mm and 2000mm, with a flat central zone (15) with sizes comprised between 1500mm and 2500mm, for working the products (13) on their larger size, wherein, at the side of the flat zone (15), there are work channels (17a, 17b, 17c) present, for at least working the edge of said large plates or ingots.

11. Method as in claim 10, characterized in that the large plates, bloom or ingot (13), after being rolled/forged on its larger size, is turned over on one side, or with respect to one edge thereof by means of a tilter device (18, 118), and then made to pass again between the rolls (12a, 12b), disposing it in correspondence with the channels (17a, 17b, 17c), the rolls (12a, 12b) being previously distanced from each other to a working gap comprised between 1300mm and 1500mm.

12. Method as in claim 10 or 11, characterized in that it provides a compression force of about 6000 tonnes with a motor that drives the rolls (12a, 12b) with a power of around 8000 Kw.

Ansprüche

1. Mehrfunktionales Walzgerüst, das zum Walzen/Schmieden von großen Platten, großen Rohblöcken, großen Rundstücken und anderen großen halbverarbeiteten Produkten (13), beispielsweise Barren oder ähnliche Produkte, geeignet ist, dadurch gekennzeichnet, dass es Walzen (12a, 12b) mit einem Durchmesser zwischen 1600 mm und 2000 mm mit einem flachen mittleren Bereich (15) mit Größen zwischen 1500 mm und 2500 mm umfasst, wobei die Walzen (12a, 12b) imstande sind, voneinander beabstandet zu sein, um in der beabstandeten Position einen Arbeitsspalt zwischen 1300 mm und 1500 mm zu definieren.

2. Walzgerüst nach Anspruch 1, dadurch gekennzeichnet, dass die linearen Größen des Walzentisches, zwischen ungefähr 3500 mm und ungefähr 4500 mm, bevorzugterweise ungefähr 4000 mm, liegen.

3. Walzgerüst nach einem der Ansprüche 1 oder 2, dadurch gekennzeichnet, dass auf der Seite des flachen mittleren Bereichs (15) Arbeitskanäle (17a, 17b, 17c) zumindest zum Bearbeiten der Kante der großen Platten, großen Rohblöcke und anderen großen halbverarbeiteten Produkte (13) vorhanden sind.

4. Walzgerüst nach Anspruch 3, dadurch gekennzeichnet, dass jede der Walzen (12a, 12b) auf zumindest einer Seite des flachen Bereichs (15) Seitenbereiche (16) mit einer Breite zwischen ungefähr 900 mm und ungefähr 1000 mm umfasst, die die Kanäle (17a, 17b, 17c) enthalten.

5. Walzgerüst nach Anspruch 4, dadurch gekennzeichnet, dass die Kanäle (17a, 17b, 17c) eine Tiefe zwischen ungefähr 60 mm und ungefähr 100 mm aufweisen.

6. Walzgerüst nach Anspruch 4, dadurch gekennzeichnet, dass die Breite der Kanäle (17a, 17b, 17c) von ungefähr 80 mm bis ungefähr 400 mm variiert.

7. Walzgerüst nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, dass es, den Rollwalzen (12a, 12b) vorgeschaltet und/oder nachgeschaltet, zumindest eine Kippervorrichtung (18, 118) zum Anordnen der großen Platte (13) auf einer Seite oder zum Umdrehen des Barrens (13) bezüglich einer seiner Kanten umfasst.

8. Walzgerüst nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, dass die Positionierungsgeschwindigkeit der Einbaustücke der Walzen (12a, 12b) während der Schritte des reziproken Bewegens der Walzen zueinander hin/voneinander weg zwischen ungefähr 60 mm/s und ungefähr 90 mm/s liegt.

9. Walzgerüst nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, dass es umkehrbar ist.

10. Verfahren zum Walzen/Schmieden von großen Platten, Rohblöcken, großen Rundstücken und anderen großen halbverarbeiteten Produkten (13), beispielsweise Barren oder ähnliche Produkte, in einem Walzgerüst nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, dass es Walzen (12a, 12b) mit einem Durchmesser zwischen 1600 mm und 2000 mm mit einem flachen mittleren Bereich (15) mit Größen zwischen 1500 mm und 2500 mm umfasst, zum Bearbeiten der Produkte (13) an ihrer größeren Abmessung, wobei auf der Seite des flachen Bereichs (15) Arbeitskanäle (17a, 17b, 17c) zumindest zum Bearbeiten der Kante der großen Platten oder Barren vorhanden sind.

11. Verfahren nach Anspruch 10, dadurch gekennzeichnet, dass die großen Platten, der Rohblock oder Barren (13), nachdem er an seiner größeren Abmessung gewalzt / geschmiedet wurde, mithilfe einer Kippervorrichtung (18, 118) auf eine Seite oder bezüglich einer Kante davon umgedreht wird und dann wieder durch die Walzen (12a, 12b) getrieben wird, wobei er den Kanälen (17a, 17b, 17c) entsprechend angeordnet wird, wobei die Walzen (12a, 12b) vorher mit einem Arbeitsspalt zwischen 1300 mm und 1500 mm zueinander beabstandet werden.

12. Verfahren nach einem der Ansprüche 10 oder 11, dadurch gekennzeichnet, dass es eine Druckkraft von ungefähr 6000 Tonnen mit einem Motor vorsieht, der die Walzen (12a, 12b) mit einer Leistung von ungefähr 8000 kW antreibt.

Revendications

1. Cage de laminage multifonction, adaptée pour laminer/forger de grandes plaques, de grands blooms, de grandes pièces rondes et d'autres produits de grande taille semi-travaillés (13), par exemple des lingots ou des produits similaires, caractérisée en ce qu'elle comprend des cylindres (12a, 12b) ayant un diamètre compris entre 1600 mm et 2000 mm, avec une zone centrale plane (15) ayant des dimensions comprises entre 1500 mm et 2500 mm, lesdits cylindres (12a, 12b) étant capables de se trouver à distance l'un de l'autre de manière à définir, dans la position éloignée, un espace de travail comprise entre 1300 mm et 1500 mm.

2. Cage de laminage selon la revendication 1, caractérisée en ce que les dimensions linéaires de la table des cylindres sont comprises entre environ 3500 mm et environ 4500 mm, avantageusement autour de 4000 mm.

3. Cage de laminage selon la revendication 1 ou 2, caractérisée en ce que, sur le côté de la zone centrale plane (15), des canaux de travail (17a, 17b, 17c) sont présents, pour au moins travailler le bord desdites grandes plaques, desdits grands blooms, et d'autres produits de grande taille semi-travaillés (13).

4. Cage de laminage selon la revendication 3, caractérisée en ce que chacun des cylindres (12a, 12b) comporte, sur au moins un côté de la zone plate (15), des zones latérales (16), ayant une largeur comprise entre environ 900 mm et environ 1000 mm, qui comprennent lesdits canaux (17a, 17b, 17c).

5. Cage de laminage selon la revendication 4, caractérisée en ce que les canaux (17a, 17b, 17c) ont une profondeur comprise entre environ 60 mm et environ 100 mm.

6. Cage de laminage selon la revendication 4, caractérisée en ce que la largeur des canaux (17a, 17b, 17c) varie d'environ 80 mm à environ 400 mm.

7. Cage de laminage selon l'une quelconque des revendications précédentes, caractérisée en ce qu'elle comprend, en amont et/ou en aval des cylindres de laminage (12a, 12b), au moins un dispositif basculeur (18, 118) afin de disposer la grande plaque (13) sur un côté ou de retourner le lingot (13) par rapport à un bord de celui-ci.

8. Cage de laminage selon l'une quelconque des revendications précédentes, caractérisée en ce que la vitesse de positionnement des empoises des cylindres (12a, 12b) au cours des étapes consistant à déplacer les cylindres réciproquement plus proches l'un de l'autre ou plus éloignés l'un de l'autre est comprise entre environ 60 mm/s et environ 90 mm/s.

9. Cage de laminage selon l'une quelconque des revendications précédentes, caractérisée en ce qu'elle est du type à inversion.

10. Procédé pour laminer/forger de grandes plaques, de grands blooms, de grandes pièces rondes et d'autres produits de grande taille semi-travaillés (13), par exemple des lingots ou des produits similaires, dans une cage de laminage selon l'une quelconque des revendications précédentes, caractérisé en ce qu'il utilise des cylindres (12a, 12b) ayant un diamètre compris entre 1600 mm et 2000 mm, avec une zone centrale plane (15) ayant des dimensions comprises entre 1500 mm et 2500 mm, pour travailler les produits (13) sur leur dimension la plus grande, dans lequel, sur le côté de la zone centrale plane (15), des canaux de travail (17a, 17b, 17c) sont présents, pour au moins travailler le bord desdites grandes plaques ou des lingots.

11. Procédé selon la revendication 10, caractérisé en ce que la grande plaque, le bloom ou le lingot (13), après avoir été laminé/forgé sur sa plus grande dimension, est retourné sur un côté, ou par rapport à un bord correspondant par l'intermédiaire d'un dispositif basculeur (18, 118), et amené ensuite à passer à nouveau entre les cylindres (12a, 12b), en le disposant en correspondance avec les canaux (17a, 17b, 17c), les cylindres (12a, 12b) étant préalablement éloignés l'un de l'autre selon un espace de travail compris entre 1300 mm et 1500 mm.

12. Procédé selon la revendication 10 ou 11, caractérisé en ce qu'il fournit une force de compression de l'ordre de 6000 tonnes, avec un moteur qui entraîne les cylindres (12a, 12b) avec une puissance de l'ordre de 8000 kW.

Drawing