Rolling mill for solid elongated products

Abstract

The invention relates to a rolling mill (1) for solid elongated products defining a rolling axis (X), comprising a first set of rolling stations (100) and a second set of rolling stations (200). Each rolling station comprises: a carrying structure; a removable roll stand box with three rolls, which are movable in the radial direction and rotatable around a respective rotation axis of three rotation axes at 120° from each other, one of which has its rotation axis in the vertical direction; three actuators mounted on the carrying structure; three gear motor groups connected to the rolls by a single extension. The position of the rolls of the second set of rolling stations is rotated around the rolling axis by 60° with respect to the position of the rolls of the first set of rolling stations, so that the rolls with vertical axis of the first set of rolling stations are arranged on a first side (1a) of the rolling mill and the rolls with vertical axis of the second set of rolling stations are arranged on a second side of the rolling mill (1) opposite to the first side with respect to the rolling axis.

Description

TECHNICAL FIELD

[0001] The present invention relates to a rolling mill for solid elongated products, such as bars or wire rods.

[0002] Advantageously, the rolling mill of the present invention is intended, in particular, for finish rolling. PRIOR ART

[0003] For many years, solid elongated products have been subjected to longitudinal rolling by means of multi-cage rolling mills with motorized rolls.

[0004] Multi-cage rolling mills comprise a plurality of rolling stations arranged in series along a rolling axis. Each rolling station comprises a plurality of rolling rolls inserted in a roll-holder cartridge or cage.

[0005] Although solutions are known with cages having two or four rolls, each cage is usually provided with three rolls. Operationally, the position of the rolls of each cage can be adjusted by varying the radial distance of each roll from the rolling axis, so as to be able to vary the rolling action according to the diameter to be obtained on the elongated product being processed.

[0006] The term "finish rolling" is used herein to indicate the step of longitudinal rolling of an elongated semi-finished product by means of a pair of rolls, so as to bring it to its final size, in the processing of elongated products, such as bars or wire rods, in the steel industry. This processing essentially causes a reduction in the size of the semi-finished product until it reaches its nominal value.

[0007] As is known, the rolling rolls are subject to wear and damage and must be replaced periodically. Therefore, in the management of the rolling mill, it is essential to facilitate the replacement of the rolls.

[0008] Usually, in multi-cage rolling mills, the replacement of the rolls first requires the removal of the corresponding cage from the structure of the rolling mill.

[0009] Typically, multi-cage rolling mills are configured for the lateral removal of the cages, i.e. by means of a movement of the cages perpendicular to the rolling axis.

[0010] Multi-cage rolling mills are known which allow the lateral removal of all the cages from the same side of the rolling mill. The lateral removal of all the cages from the same side of the rolling mill is very advantageous, as it simplifies the logistics of managing the cages themselves.

[0011] Figure 1 And Figure 2An example of a multi-stand rolling mill from which all the stands are extracted from the same side is shown.

[0012] In particular, the rolling mill comprises four or five stands placed in series along the rolling axis. Each stand S is provided with three rolls R1, R2 and R3 uniformly distributed at 120° with respect to each other around the rolling axis X. One of the three rolls R1 has a horizontal rotation axis. The rolls of the odd stands are rotated around the rolling axis by 60° with respect to the even stands to roll the material on the part of the product not affected by the action of the rolls in the preceding stand with the groove bottom of the respective roll. For this configuration, the odd stands are inverted around the horizontal axis with respect to the even stands. Each roll is provided with its own adjustment actuator A1, A2 and A3, in particular of the hydraulic type, which is mounted on the fixed structure F of the rolling mill. The purpose of the adjustment actuators A1, A2 and A3 is to adjust the radial distance of each roll from the rolling axis in order to be able to vary the rolling action according to the diameter to be obtained on the elongated product being processed. The adjustment actuators are radially aligned with the respective rolls and are therefore uniformly distributed at 120° around the rolling axis X. In the configuration shown in the figures, therefore, one of the three actuators is arranged along the vertical (or "perpendicular") direction passing through the rolling axis. Figure 1 and Figure 2 A cross-sectional view of the rolling mill at an even stand is shown.

[0013] The control system of the rolling mill comprises a single motor M for each stand, which is connected to the respective rolls through a three-output gear distributor group RD. The horizontal-axis roll R1 is directly connected to the distributor gear group through a kinematic connection extension L1, while each of the two inclined rolls R2 and R3 is connected to the gear distributor group RD through a double extension L2+L2' and L3+L3' with a dedicated angular gearbox G2, G3 between them. The motors and the distributor gear groups of the different stands are all located on the same side of the rolling mill, so that the opposite side can be used for free extraction of the stands. During the extraction step of the stands (to allow the free path for the movement of the stands to be generated), the hydraulic actuator A2 of the roll R2 located on the extraction side of the stand can be rotated (which is shown in the figures in the rotated non-operating condition), so that it can be temporarily removed from the extraction path.

[0014] Although this rolling mill is effective, it also has some limitations.

[0015] The control system comprises, for each stand, a three-output gear distributor group RD and dedicated angular gearboxes G2 and G3 (with an included angle between the input and output shafts of about 50-60°), so it is complex and expensive.

[0016] Moreover, the special bevel gearboxes G2 arranged below the rolling mill and connected to the respective rolls with an extension L2' at 30° with respect to the vertical are inevitably affected by the discharge of cooling water. Once reached the gearbox G2, the water penetrates the lubrication system, reaching the other gearboxes. This causes corrosion problems, not only affecting the double extension L2+L2' and the lower bevel gearboxes G2, but also all the gearboxes, with consequent high maintenance costs.

[0017] Figure 3 and Figure 4 A second example of a rolling mill is shown, which extracts the holders laterally on the same side. The general configuration of the rolls and of the control system of this rolling mill is similar to that of the rolling mill shown in Figure 1 But, the radial adjustment system of the rolls is integrated on each roll stand box, consisting of a mechanical adjustment system adapted to adjust the radial movement of each roll synchronously. The movement of this adjustment system is provided by an external control device C, which is installed on a fixed structure of the rolling mill on the side of extraction of the holders. This external control device C is rotatable with respect to the fixed structure F to create a free path for the extraction of the holders.

[0018] However, even in this solution, the aforementioned limitations associated with the complexity and cost of the control system and the presence of special bevel gearboxes placed below the rolling mill and thus exposed to the discharge of cooling water remain.

[0019] To overcome the aforementioned limitations, a multiple-holder rolling mill has been proposed, which has the following structure:

[0020] - a simplified control system, which comprises a gear motor group for each roll of each holder, and a movement connection extension between the gear motor group and the respective roll, without a special bevel gearbox;

[0021] - a (hydraulic) roll adjustment actuator, which is located outside the holder and is fixedly associated with the structure of the rolling mill;

[0022] - a different arrangement of the three rolls inside the holder.

[0023] Multiple-holder rolling mills of this type are described, for example, in WO2009141414A1 and EP2560771B1.

[0024] In particular, each cage is provided with three rolls, which are uniformly distributed at 120° with respect to each other around the rolling axis. One of the three rolls has a vertical rotation axis, instead of a horizontal rotation axis. The rolls of the odd cages are rotated at 60° around the rolling axis with respect to the even cages. Each roll is provided with its own adjustment actuator, in particular of the hydraulic type, which is mounted on the fixed structure of the rolling mill. These adjustment actuators are radially aligned with the respective rolls, thus being uniformly distributed at 120° around the rolling axis, and, as a consequence, one of them is located in the horizontal direction through the rolling axis. Thanks to this arrangement of the rolls and to the absence of a dedicated angular gearbox located below the rolling mill, problems related to the infiltration of water into the lubrication system are avoided.

[0025] The extraction of each cage takes place on the side opposite to that of the roll with vertical axis, after clearing the path by moving the connecting extension of one of the inclined rolls. However, with this configuration, it can not be possible to extract the cages on the same side of the rolling mill, but rather the even cages on one side and the odd cages on the other side.

[0026] Therefore, the rolling mill described in WO2009141414A1 and EP2560771B1, although significantly simplifying the equipment, does not have the operational advantages related to the fact of being able to extract all the cages from the same side of the rolling mill.

[0027] So far, there has not been a multi-cage rolling mill which both allows the extraction of all the cages from the same side of the rolling mill, while having a simplified roll control system which does not require a dedicated angular gearbox.

[0028] In the field of rolling mills for solid elongated products, the differentiated requirement of roll calibration requires more frequent replacement of the rolls. For this reason, in this field, there is a greater need for a multi-cage rolling mill which combines the possibility of extracting all the cages from the same side with a simplified roll control system which does not require a dedicated angular gearbox. SUMMARY

[0029] Therefore, the main purpose of the present invention is to eliminate or at least reduce the drawbacks of the prior art described above, by providing a rolling mill for solid elongated products which combines the possibility of extracting all the cages from the same side with a simplified roll control system which does not require a dedicated angular gearbox.

[0030] Another purpose of the present invention is to provide a rolling mill for solid elongated products which is structurally simple to manufacture and which is manufactured at much lower manufacturing costs than the traditional solutions which allow the extraction of all the cages from the same side of the rolling mill. BRIEF DESCRIPTION OF DRAWINGS

[0031] The technical characteristics of the application according to the purposes set out above emerge clearly from the annexed claims, the advantages of which will also become more apparent from the part of the detailed description which follows, with reference to the attached drawings, which show one or more purely exemplary and non-limiting embodiments of the application, in which:

[0032] Figure 1 a partial view of a first example of a rolling mill of the traditional type for solid elongated products, which allows all the cages to be extracted from the same side thereof, is shown, the view being a cross-sectional view at an even number of cages;

[0033] Figure 2 a partial view of a second example of a rolling mill of the traditional type for solid elongated products, which allows all the cages to be extracted from the same side thereof, is shown, in which the external control means of the radial roller adjustment system shown are inoperative; Figure 1 a partial enlarged view of the intermediate rolling mill is shown;

[0034] Figure 3 a partial view of a second example of a rolling mill of the traditional type for solid elongated products, which allows all the cages to be extracted from the same side thereof, is shown, in which the external control means of the radial roller adjustment system shown are inoperative;

[0035] Figure 4 a partial view of a second example of a rolling mill of the traditional type for solid elongated products, which allows all the cages to be extracted from the same side thereof, is shown, in which the external control means of the radial roller adjustment system shown are inoperative; Figure 3 a partial view of a second example of a rolling mill of the traditional type for solid elongated products, which allows all the cages to be extracted from the same side thereof, is shown, in which the external control means of the radial roller adjustment system shown are inoperative;

[0036] Figure 5 a schematic view of the distribution of the rolling stations along the rolling axis in the rolling mill of the application is shown;

[0037] Figure 6 a schematic view of the arrangement of the rollers in a rolling station belonging to the first group of rolling stations in the rolling mill of the application is shown;

[0038] Figure 7 a schematic view of the arrangement of the rollers in a rolling station belonging to the second group of rolling stations in the rolling mill of the application is shown;

[0039] Figure 8 a cross-sectional view of a preferred embodiment of the rolling mill of the application is shown, the view being a cross-sectional view along a plane orthogonal to the rolling axis upstream of the inlet of a rolling station immediately following the first group of rolling stations, in which the relative roller support box of the rolling station is in an operable position (operably connected to the actuation means of the roller control system and of the roller adjustment system);

[0040] Figure 9 a partial view of a second example of a rolling mill of the traditional type for solid elongated products, which allows all the cages to be extracted from the same side thereof, is shown, in which the external control means of the radial roller adjustment system shown are inoperative; Figure 8 a partial view of a second example of a rolling mill of the traditional type for solid elongated products, which allows all the cages to be extracted from the same side thereof, is shown, in which the external control means of the radial roller adjustment system shown are inoperative;

[0041] Figure 10 a partial view of a second example of a rolling mill of the traditional type for solid elongated products, which allows all the cages to be extracted from the same side thereof, is shown, in which the external control means of the radial roller adjustment system shown are inoperative; Figure 8the same section view of the rolling station, in which the relative roll chock of the rolling station is in the extraction position (disconnected operatively from the control system and from the adjustment system);

[0042] Figure 11 is shown Figure 10 is shown

[0043] Figure 12 is shown

[0044] Figure 13 is shown Figure 12 is shown

[0045] Figure 14 is shown Figure 12 the same section view of the rolling station, in which the relative roll chock of the rolling station is in the extraction position (disconnected operatively from the control system and from the adjustment system);

[0046] Figure 15 is shown Figure 14 is shown

[0047] Figure 16 is shown

[0048] Elements or parts of elements that are common to the following embodiments are denoted with the same reference numerals. DETAILED DESCRIPTION

[0049] The present invention relates to a rolling mill for solid elongated products in the steel industry, such as bars and wire rods.

[0050] Advantageously, the rolling mill of the present invention is intended, in particular, for finishing rolling.

[0051] The term "finishing rolling" is used herein to indicate the step of longitudinal rolling of an elongated semi-finished product by means of a pair of rolls to bring it to its final dimensions in the processing of elongated products (e.g. bars or wire rods) in the steel industry. This processing essentially causes a reduction in the dimensions of the semi-finished product until it reaches its nominal value.

[0052] Reference is made to Figures 5 to 16, the reference number 1 as a whole denotes a rolling mill for solid elongated products of the iron and steel industry, according to the present application.

[0053] In this and in the following description and in the appended claims, reference is made to a rolling mill 1 in use. Therefore, any reference to lower or higher positions, or horizontal or vertical directions, is to be interpreted in such a condition.

[0054] The rolling mill 1 for solid elongated products defines a rolling axis X along which the elongated product to be rolled slides.

[0055] According to a general embodiment of the application, the rolling mill 1 comprises a first group (i.e. a first plurality) of rolling stations 100 and a second group (i.e. a second plurality) of rolling stations 200, the first and second groups of rolling stations being placed in series along the rolling axis X and alternating with each other between an input end and an output end of the rolling mill 1. This configuration of the rolling mill 1 is schematically shown in Figure 5 , in which each rolling station 100 and 200 (for example, a total of six) is schematically shown with a rectangle.

[0056] Each of the above-mentioned rolling stations 100 or 200 comprises:

[0057] - a carrying structure 110, 210, and

[0058] - a roll-holder cartridge 120, 220, which is connected in a removable manner to the carrying structure 110, 210, so as to be extractable from the carrying structure itself for replacement and / or maintenance.

[0059] Preferably, as shown in Figures 8 to 15 , the carrying structure 110, 210 of each rolling station is fixed to a common ground support base 2, which extends parallel to the aforesaid rolling axis X.

[0060] Advantageously, each carrying structure 110, 210 defines an operating housing seat 4 for the roll-holder cartridge. This housing seat 4 is delimited at the bottom by a horizontal bottom wall 5, which acts as a support base for the roll-holder cartridge 120, 220 inside the housing seat 4.

[0061] Preferably, the carrying structure of each rolling station can comprise a support structure 6 for the roll-holder cartridge, which constitutes an extension of the aforesaid horizontal bottom wall 5 outside the housing seat 4. This support structure 6 acts as a support base for the roll-holder cartridge outside the housing seat 4.

[0062] For example, as shown in Figure 11 and Figure 15As shown, each roll stand box 120 or 220 comprises three rolling rolls 131, 132, 133 or 231, 232, 233 mounted on the roll stand box itself so as to be movable radially with respect to the rolling axis X along the respective radial axes T1, T2, T3 passing through the rolling axis.

[0063] As shown schematically in Figure 6 and Figure 7 As shown schematically in each roll stand box 120 or 220, the three rolling rolls 131, 132, 133 or 231, 232, 233 are rotatable about three respective rotation axes R1, R2, R3, which are arranged 120° with respect to each other. One of the rolling rolls 131, 231 has its own rotation axis R1 in the vertical direction, while the other two rolling rolls 132, 133 or 232, 233 have respective rotation axes R2, R3 inclined with respect to the vertical direction. The inclined rotation axes R2, R3 each form an angle of 60° with respect to the vertical direction.

[0064] Each of the rolling stations 100 or 200 described above comprises three actuators 141, 142, 143 or 241, 242, 243 mounted on the carrying structure 110, 210, and each actuator is adapted to act on the respective rolling roll 131, 132, 133 or 231, 232, 233 along three respective radial axes T1, T2, T3 arranged 120° with respect to each other.

[0065] The "radial axis" T1, T2, T3 of a rolling roll means an axis which is orthogonal to the rotation axis R1, R2, R3 of the rolling roll and to the rolling axis X.

[0066] In operation, each actuator is adapted to act on the respective rolling roll so as to maintain a predetermined radial distance of the same rolling roll 131, 132, 133 or 231, 232, 233 from the rolling axis X. The predetermined radial distance can be adjusted according to the nominal dimensions of the elongated product to be rolled, and it can be adjusted to optimize its tolerances by receiving values continuously measured by specific measuring systems located downstream of the rolling mill.

[0067] The group of three actuators of a rolling station defines a radial adjustment system of the respective rolling rolls of the rolling station itself.

[0068] Each of the aforementioned rolling stations 100 or 200 also comprises three gear motor groups 161, 162, 163 or 261, 262, 263 connected to the respective rolls by single extensions 171, 172, 173 or 271, 272, 273 in order to provide the torque necessary to impart rotation to the rolls themselves and to advance the product along the rolling axis X. In other words, as shown in the attached drawings, each single rolling station 100 or 200 is provided with three single extensions, one for each gear motor group and associated roll.

[0069] In each rolling station, the group of three gear motor groups and the respective single extension associated therewith constitute a control system of the rolls with a single control device.

[0070] By comparing, for example, Figure 9 and Figure 13 it can be seen that the position of the rolls 231, 232, 233 of the second group of rolling stations 200 is rotated by 60° about the rolling axis X with respect to the position of the rolls of the first group of rolling stations 100.

[0071] Thanks to this angular arrangement of the rolls rotating between the first group of rolling stations 100 and the second group of rolling stations 200, it is possible to roll the product sliding along the rolling axis in a uniform manner. In a given rolling station, the grooved bottom of the rolls in fact acts on the portion of the product that was not affected by the action of the rolls in the preceding rolling station.

[0072] Moreover, thanks to the above-mentioned angular arrangement of the rolls rotating between two consecutive rolling stations, the rolls with vertical axis 131 of the first group of rolling stations 100 are arranged on the first side la of the rolling mill 1, while the rolls with vertical axis 231 of the second group of rolling stations 200 are arranged on the second side lb of the rolling mill 1, opposite the first side with respect to the rolling axis X.

[0073] The arrangement of the rolls in the first group of rolling stations 100 and in the second group of rolling stations 200 is shown in a simplified manner, respectively, in Figure 6 and Figure 7 It can be observed that the rolls with vertical axis 131, 231 have respective associated horizontal radial axes T1, while the inclined rolls 132, 133 and 232, 233 have their respective radial axes T2 and T3 inclined by 30° with respect to the vertical. With respect to the horizontal plane passing through the rolling axis X, it is also possible to identify the upper inclined rolls 132, 232 and the lower inclined rolls 133, 233.

[0074] By "roll arranged (or located) on a side of the rolling mill" it is meant that the roll extends in the horizontal direction from the rolling axis radially towards the outside of the rolling mill on that side.

[0075] According to the application, all the rolling stations 100, 200 of the rolling mill 1 are configured to allow the lateral extraction of the respective roll stand cartridge 120 and 220 from the same side of the rolling mill 1, hereinafter referred to as "cartridge extraction side".

[0076] Such cartridge extraction side, which is the same for all the rolling stations 100 and 200, can correspond to:

[0077] - the aforementioned first side la, i.e. the side of the rolling mill 1 in which the rolling mills 131 with vertical axis of the first group of rolling stations 100 are arranged; or

[0078] - the aforementioned second side lb, i.e. the side of the rolling mill 1 opposite to the first side and in which the rolling mills 231 with vertical axis of the second group of rolling stations 200 are arranged.

[0079] Preferably, as shown in the attached figures, the cartridges 120, 220 are extracted from the relative rolling stations 100, 200 along an extraction path lying on a horizontal plane defined by the aforementioned horizontal bottom wall 5 and by the support structure 6 located outside the housing seat 4.

[0080] Still according to the application, the actuators of the rolling mills with vertical axis of the rolling stations arranged on the cartridge extraction side are movable with respect to the carrying structure.

[0081] Operationally, the possibility of moving these actuators is aimed at freeing the extraction path for the relative roll stand cartridge. In these rolling stations, the actuators of the rolling mills with inclined axis are fixed with respect to the relative carrying structure.

[0082] All the actuators of the rolling mills of the rolling stations arranged on the side opposite to the cartridge extraction side are fixed with respect to the carrying structure. In fact, in these rolling stations, none of the actuators is arranged along the cartridge extraction path.

[0083] Figures 8 to 15 An embodiment of the rolling mill 1 is shown, in which the cartridge extraction side is the first side la, therefore the rolling stations with movable actuators are the rolling stations 100 of the first group of rolling stations, while the rolling stations with all the fixed actuators are the rolling stations 200 of the second group of rolling stations.

[0084] Obviously, such an embodiment of the rolling mill 1 can be provided, in which the aforementioned extraction side is the second side lb, therefore the rolling stations with movable actuators are the rolling stations 200 of the second group of rolling stations, while the rolling stations with all the fixed actuators are the rolling stations 100 of the first group of rolling stations.

[0085] Preferably, each rolling station 100 with movable actuators is provided with means 144 for moving the actuators 141 operatively associated with the rolls with vertical axis between the operating position and the non-operating position. Such moving means 144 can be of any kind, provided that they are suitable for the purpose. In the illustrated embodiment, the moving means 144 consist of hydropneumatic cylinders arranged above the respective rolling station 100, 200 by means of a bracket or scaffold 164. Figures 8 to 11 In the illustrated embodiment, the moving means 144 consist of hydropneumatic cylinders arranged above the respective rolling station 100, 200 by means of a bracket or scaffold 164.

[0086] Furthermore, the single extensions 171, 172, 173 and 271, 272, 273 of all the rolling stations 100, 200 are movable with respect to the load-bearing structure 110, 210 of the respective rolling station so as to be able to disengage the respective rolls 131, 132, 133 and 231, 232, 233 and possibly release the extraction path of the roll-holder boxes.

[0087] The rolling mill 1 for solid elongated products having the above-mentioned characteristics combines the possibility of extracting all the roll-holder boxes from the same side with a simplified control system of the rolls that does not require specific angular gearboxes.

[0088] As already emphasized, the control system of the rolls of each rolling station consists of three gear motor groups 161, 162, 163 or 261, 262, 263 associated with the respective rolls by means of a single extension 171, 172, 173 or 271, 272, 273. Therefore, the control system provides a dedicated gear motor group for each roll. By virtue of this, each gear motor group can be spatially arranged according to the position of the respective roll, with the kinematic connection between the gear motor group and the roll being defined by the single extension. This avoids the need to adopt a kinematic connection solution with double extensions mutually connected by specific angular gearboxes, which is inevitable in the case of rolling mills in which all the rolls of the roll-holder boxes use a single motor control system.

[0089] By virtue of this configuration of the control system and the spatial distribution of the rolls, in which the rolls in each rolling station provide a roll with vertical axis of rotation, in each rolling station it is also possible to arrange one of the three above-mentioned extensions in the vertical direction, with the remaining two extensions (dedicated to the two above-mentioned inclined rolls) lying on two axes substantially at 60° with respect to the vertical direction. In other words, in all the rolling stations it is possible to avoid, in a simple manner, having an extension (with the associated gear motor group) directly below the rolling station, making it easier to carry out maintenance activities.

[0090] With the present application, in addition to the movement of the extensions, the preparation of the free path on the same side of the rolling mill requires only the movement of the actuators dedicated to the rolls with vertical axis. As already pointed out, it should be noted that the movement of these actuators is not necessary in all rolling stations, but only in the rolling stations with vertical axis rolls arranged on the side of the box extraction.

[0091] The above configuration of the control system also avoids positioning the gearboxes directly below the rolling stations. This fundamentally avoids problems related to the infiltration of water through the gearboxes into the lubrication system.

[0092] Preferably, as shown in the attached figures, the single extensions 171, 172, 173 and 271, 272, 273 are arranged, when operatively connected to the respective rolls 131, 132, 133 and 231, 232, 233, substantially aligned in the axial direction with the rotation axes Rl, R2, R3 of the respective rolls 131, 132, 133 and 231, 232, 233.

[0093] By "extension with axis aligned with the rotation axis of the respective roll" it is meant the average aligned position occurring in the transmission of the movement to the roll, excluding the radial adjustment of the roll optimized according to the nominal dimensions of the product, and tolerances.

[0094] In this way, preferably, in each rolling station, the extension 171, 271 dedicated to the roll with vertical axis is arranged in the vertical direction, while the remaining two extensions 172, 173 and 272, 273, dedicated to the two inclined rolls, are arranged on two axes substantially at 60° with respect to the vertical direction.

[0095] According to the embodiment shown in the attached figures, the extension 171, 271 associated with the roll 131, 231 with vertical axis is arranged in the vertical direction in the axial direction and is associated with a respective gear motor group 161, 261, wherein each gear motor group comprises a motor 161a, 261a arranged horizontally and an angular gearbox 161b, 261b, wherein the input and output shafts of the angular gearbox form an angle of 90°. In particular, each of such gear motor groups 161, 261 is supported above the respective rolling station 100, 200 by a bracket or scaffold 164, 264.

[0096] According to an alternative embodiment, not shown in the drawings, the extensions 171, 271 associated with the rolls 131, 231 having a vertical axis are arranged in the vertical direction in the axial direction and can be associated with respective gear motor groups 161, 261, each of which comprises a motor arranged in the vertical direction and a gearbox having parallel input and output shaft axes. In particular, each of such gear motor groups 161, 261 is supported above the respective rolling station 100, 200 by a bracket or scaffold 164, 264.

[0097] Preferably, the extensions 172, 173 and 272, 273 associated with the rolls 132, 133 and 232, 233 having an inclined axis are associated with respective gear motor groups 162, 163 and 262, 263, each of which comprises a motor and a gearbox having parallel input and output shaft axes. In particular, as shown in the drawings, each of these gear motor groups 162, 163 and 262, 263 is arranged on a base 3a or 3b (foundation) defined by a slope (preferably 60° with respect to the vertical direction), where the base 3a or 3b extends alongside the common ground support base 2 on one side of the rolling mill 1a or 1b parallel to the rolling axis X. Alternatively, the base 3a or 3b (foundation) can define a horizontal plane and the gear motor groups are mounted on the base with the necessary inclination angle.

[0098] Preferably, the gear motor groups 161, 162, 163 and 261, 262, 263 of all the rolling stations are fixedly mounted on respective support seats. In this case (totally preferred), as will be clarified in the following, the movement that disengages the extensions from the rolls (and possibly releases the extraction path of the roll holder box) is obtained by moving only the extensions, thus not affecting the gear motor groups. This significantly simplifies the system.

[0099] As highlighted above, the single extensions of all the rolling stations 100, 200 can be moved with respect to the load-bearing structure 110, 210 to disengage the respective rolls 131, 132, 133 and 231, 232, 233 and possibly release the extraction path of the roll holder box.

[0100] Preferably, the extensions 171, 172, 173 and 271, 272, 273 of all the rolling stations 100, 200 can be moved with respect to the load-bearing structure of the respective rolling station by at least one translational movement along their axis.

[0101] According to the preferred embodiment shown in the attached drawings, the single extensions 171, 172, 173 and 271, 272, 273 have a telescopic structure. In this case, the above-mentioned translational movement of the extensions along their own axis (for disengaging the respective roller and possibly releasing the extraction path of the roller-holder box) can be obtained by an axial sliding movement between two or more distinct portions of the telescopic structure of the single extension.

[0102] According to an embodiment not shown in the drawings, the single extensions 172, 173 and 271, 272, 273 can be configured to be able to slide along the gearbox shaft of the respective gear motor group. This sliding movement would cause the extension to translate along its own axis. This axial sliding allows the extension to disengage from the hub of the respective roller and, if necessary, to release the extraction path of the relative roller-holder box.

[0103] The adoption of telescopic extensions can be used instead of or in combination with the adoption of extensions that slide along the shaft of the respective gear motor group.

[0104] According to the preferred embodiment shown in the drawings, in all the rolling stations 100, 200, at least one of the single extensions 172, 272 can be subjected to a rotational translation movement to disengage the respective roller 132, 232, to release the relative roller-holder box for its extraction and, if necessary, to release the extraction path of the roller-holder box itself.

[0105] From an operational point of view, with the same width of translational movement, the rotational translation allows the extension to be removed from the relative roller-holder box more significantly than with a pure (simple) translation, thus making it possible to release the path for the extraction of the roller-holder box from the rolling mill without excessive translational travel.

[0106] This solution can be used for all the extensions of the rolling stations. However, this solution is preferably used only for the extensions 172, 272 operatively associated with the upper inclined rollers 132, 232. In fact, as can be observed in particular in Figure 9 and Figure 13 , the extensions that most invade the operating housing seat 4 are the extensions 172, 272 associated with the upper inclined rollers 132, 232.

[0107] It should be noted that for the extensions 272 associated with the upper inclined rollers in the rolling stations having vertical rollers provided on the side opposite to the box extraction side, the solution with rotational translation movement is preferably adopted. In fact, in these rolling stations, the extensions of the upper inclined rollers are positioned along the box extraction path, for which their full movement is important.

[0108] Differently, the extensions 173, 273 associated with the downward inclined rollers 133, 233 and the extensions 171, 271 associated with the vertical rollers 131, 231 intrude much less into the respective operating housing seat 4, thus requiring a more limited width of movement, which can be achieved by a purely (simple) axial translation.

[0109] Preferably, each rolling station 100, 200 with movable actuators is provided with means 174, 175 for moving the respective extension. Such moving means 174, 175 can be arbitrary, provided that they are suitable for the purpose.

[0110] In Figures 8 to 15 In the illustrated embodiment, such moving means can consist of a simple lever mechanism 174 actuated by a hydraulic pneumatic cylinder piston to generate a purely translational movement (in particular for the extensions 171, 173, 271, 273). Alternatively, the moving means can consist of devices 175 mounted on a rotatable base for the axial translation of the extensions to generate a rotational translational movement (for the extensions 172, 272).

[0111] Advantageously, each of the actuators 141, 142, 143 and 241, 242, 243 comprises:

[0112] - a control element adapted to directly engage the respective roller; and

[0113] - control means adapted to actuate said control element.

[0114] According to the embodiment illustrated in the attached drawings, the actuators can be entirely mounted on the load-bearing structure 110, 210 of the respective rolling station. In this case, both the control means and the control element are mounted on the load-bearing structure 110, 210.

[0115] In particular, as illustrated in the attached drawings, the actuators 141, 142, 143 and 241, 242, 243 can consist of a hydraulic capsule, in which the respective control element consists of a piston 151, 152, 153 and 251, 252, 253 movable along the radial axis T1, T2, T3 of the respective roller. As an alternative to the hydraulic capsule, the actuators can be of the mechanical type. In this case, preferably, the respective control element consists of an adjustment screw movable along the radial axis T1, T2, T3 of the respective roller.

[0116] According to an embodiment not shown in the drawings, the actuators can be partially mounted on the load-bearing structure 110, 210 of the respective rolling station. In this case, the control device is mounted on the load-bearing structure, while the adjustment elements are mounted on the respective roll stand box. Preferably, in this case the actuators are of the mechanical type, in which, in particular, the respective adjustment elements consist of adjustment screws movable along the radial axis T1, T2, T3 of the respective roll.

[0117] In the case where the actuators are completely mounted on the load-bearing structure of the respective rolling station, whether they are hydraulic containers or mechanical actuators, the actuators 142, 143 and 242, 243 associated with the rolls with inclined axis of each rolling station are preferably arranged so that, when the relative adjustment elements 152, 153 and 252, 253 are completely retracted, an unobstructed extraction path of the respective roll stand box is created, parallel to the radial axis of the actuators 141, 241 associated with the rolls with vertical axis.

[0118] Preferably, this configuration of the actuators is adopted in the rolling stations 200 in which the rolls with vertical axis are arranged on the side opposite to the extraction side. In this case, in fact, the adjustment elements of the actuators associated with the inclined rolls, if not completely retracted, would be positioned along the extraction path of the roll stand box, thus creating an undercut for the roll stand box itself. On the other hand, the actuators associated with the rolls with vertical axis do not lie along the extraction path, the relative adjustment elements can always be kept in an advanced position.

[0119] In more detail, the rolling stations 200 with vertical axis rolls arranged on the side opposite to the extraction side are configured so that, when the adjustment elements 152, 153, 252, 253 of the actuators 142, 143, 242, 243 associated with the two inclined rolls are completely retracted, the minimum distance between the adjustment elements of the two actuators is greater than the maximum overall size of the roll stand box measured in the same direction.

[0120] The aforementioned configuration of the actuators can not be adopted in the rolling stations 100 in which the rolls with vertical axis are arranged on the extraction side. In this case, in fact, the actuators associated with the inclined rolls do not lie on the box extraction path. Therefore, even if the respective adjustment elements are not completely retracted, they in any case do not lie along the extraction path of the roll stand box and do not create an undercut for the roll stand box itself. The actuators of the vertical rolls do not present the problem of the complete or partial retraction of the adjustment elements. In fact, this actuator must in any case be moved as a block to release the extraction path.

[0121] Advantageously, each rolling station 100, 200 can comprise means 300 for moving the respective roll stand box along the box extraction path.

[0122] In particular, the means 300 can be adapted to move the roll stand box out of the operating housing seat 4 and to bring it inside said housing seat.

[0123] Preferably, said moving means 300 are placed on the side 1 b of the rolling mill 1 opposite the box extraction side la.

[0124] More specifically, during the box extraction step, the means 300 exert a pushing action on the roll stand box, while during the positioning of the roll stand box inside the housing seat 4, the means 300 exert a pulling action on the box.

[0125] Thanks to this configuration, the moving means 300 are never positioned inside the space for handling and changing the roll stand box. This allows to always have free space for roll stand box handling and changing, allowing to connect directly from the rolling mill to the roll stand box maintenance workshop. This configuration also simplifies the structure of the moving means. In particular, no particular structural measures are necessary to prevent the moving means from hindering the movement of the roll stand box.

[0126] According to a preferred embodiment shown in the attached drawings, the above-mentioned moving means 300 consist of at least one hydraulic pneumatic cylinder.

[0127] More specifically, the hydraulic pneumatic cylinder 300 is arranged so as to act in an axial direction parallel to the aforesaid horizontal bottom wall 5, which acts as a support base for the roll stand box 120, 220 inside the housing seat 4, and to the aforesaid support structure 6 of the roll stand box, which constitutes an extension of the horizontal bottom wall 5 outside the housing seat 4. Preferably, the hydraulic pneumatic cylinder is arranged close to the sliding face of the roll stand box, so as to exert its action on the base of the roll stand box itself.

[0128] Operationally, once the three extensions and three actuators of a rolling station are disengaged from the rolls of the respective roll stand box and a free path from the housing seat towards the outside of the box extraction side la has been prepared, the moving means are activated. Then, the means 300 push the roll stand box from the housing seat 4 through the support structure 6 to a double-position change carriage 310, which receives the used roll stand box extracted from the rolling mill and, after translating along an axis parallel to the rolling axis X, brings the new roll stand box in position to be inserted into the housing 4 by the means 300.

[0129] Preferably, as shown for example in Figure 10 the same carriage 310 can be directly connected to the maintenance workshop by means of a rail transport system.

[0130] Advantageously, each rolling station 100, 200 is provided with a system for detecting the radial position of each of the respective rolls, so that the action of the actuators on the rolls themselves can be adjusted.

[0131] Preferably, at least in the rolling stations 100 provided with actuators 141, 241, which are movable with respect to the load-bearing structure, the system for detecting the radial position of the rolls is mounted on the respective roll chock and can be operatively connected to the respective actuator.

[0132] More specifically, as shown for example in Figure 16 such a detection system on the roll chock comprises a transducer 331, 332, 333 for each roll 131, 132, 133. Each transducer detects the radial position of the respective roll and is adapted to transmit it to the respective actuator, so that the latter can be adjusted accordingly.

[0133] By virtue of such a detection system on the roll chock, the actuators are provided with correct information on the radial position of the rolls, without being affected by the asymmetric movements under the load of the actuators themselves, due to the fact that in the rolling stations 100 of the first group of rolling stations the actuators 141 are movable with respect to the load-bearing structure, while the other two actuators 142, 143 are fixed.

[0134] Operationally, the fact of having a movable actuator 141 would entail the drawback of a lower repeatability of the measurement of the radial position of the respective roll, due to the movement play and wear with respect to the fixed actuators and greater slack under load. By adopting an on-board detection system, this drawback is eliminated.

[0135] As mentioned above, the system for detecting the radial position of the rolls on the roll chock can be adopted only in the rolling stations 100 with actuators movable with respect to the load-bearing structure of the rolling station. However, such an on-board chock detection system can also be used in rolling stations with all fixed actuators, to simplify the components of the rolling mill 1, the maintenance and the logistical management.

[0136] The present application allows to obtain the many advantages already explained in the course of the description.

[0137] The rolling mill 1 for solid elongated products of the present application combines the possibility of taking out all the cages from the same side with a simplified system of control of the rolls that does not require specific angular gearboxes.

[0138] The rolling mill 1 for solid elongated products of the present invention is also easy to manufacture in terms of structure, with significantly lower manufacturing costs compared to the traditional solutions that allow all the rolling mill roller stand boxes to be extracted from the same side of the rolling mill, especially considering the fact that the gearboxes of the rolling mill of the present invention are standard, thus easily available on the market at significantly lower costs. There is also an advantage related to the position of the lower gearbox. The latter is far from the rolling shaft, far from the heat sources, water and flakes of the rolling mill, thus, more reliable and easier to access when maintaining.

[0139] Therefore, the present invention thus conceived achieves the intended purposes.

[0140] Obviously, in its practical implementation, different forms and configurations from those described above can also be adopted, without departing from the scope of protection of the present invention.

[0141] Moreover, all the details can be replaced by technically equivalent elements and the dimensions, forms and materials adopted can be arbitrary, depending on the requirements.

Claims

1. A rolling mill (1) for solid elongated products defining a rolling axis (X), comprising a first group of rolling stations (100) and a second group of rolling stations (200) arranged in series along the rolling axis (X) alternated to each other between an input end and an output end of the rolling mill (1), wherein, Each of said rolling stations comprises: - a supporting structure (110, 210); - a rolling stand box (120, 220) removably connected to said supporting structure (110, 210) and comprising three rolling rolls (131, 132, 133; 231, 232, 233) mounted on said rolling stand box (120, 220) so as to be movable radially with respect to said rolling axis (X); said three rolls being rotatable about three respective rotation axes (R1, R2, R3) of which the three rotation axes (R1, R2, R3) are mutually 120° and the rotation axis (R1) of one of said three rolls (131, 231) is vertical, while the respective rotation axes (R2, R3) of the other two rolls (132, 133; 232, 233) are inclined with respect to said vertical direction; - three actuators (141, 142, 143; 241, 242, 243) mounted on said supporting structure (110, 210), each of which is adapted to act on a respective roll (131, 132, 133; 231, 232, 233) along three respective radial axes (T1, T2, T3) of which the three radial axes (T1, T2, T3) are mutually 120°, maintaining each of said three rolls (131, 132, 133; 231, 232, 233) at a predetermined radial distance from said rolling axis (X); - three gear motor groups (161, 162, 163; 261, 262, 263) connected to said rolls by means of a single extension (171, 172, 173; 271, 272, 273) for each of said groups, so as to provide the rotation of said rolls and the torque necessary to advance the product along said rolling axis (X); wherein the position of the rolls (231, 232, 233) of said second group of rolling stations (200) is rotated by 60° about said rolling axis (X) with respect to the position of the rolls of said first group of rolling stations (100), so that the roll (131) with vertical axis of said first group of rolling stations (100) is arranged at a first side (1a) of said rolling mill (1), and the roll (231) with vertical axis of said second group of rolling stations (200) is arranged at a second side (1b) of said rolling mill (1), said second side (1b) being opposite to said first side with respect to said rolling axis (X); characterized in that all of said rolling stations (100, 200) of said rolling mill (1) are configured to allow the lateral extraction of the respective rolling stand box (120, 220) from the same side of said rolling mill (1), said same side of said rolling mill (1) corresponding to said first side (1a) or to said second side (1b). The actuators (141) of the rollers with vertical axis (131) of the rolling station (100) on the box extraction side (1a) are movable with respect to the load structure (110) in order to release the extraction path of the roller-holder box, while the actuators (142, 143) of the rollers with inclined axis (132, 133) are fixed with respect to the load structure (110); The actuators (241, 242, 243) of the rollers (231, 232, 233) of the rolling station (200) on the opposite side (1b) of the box extraction side are all fixed with respect to the load structure (210); Each single extension (171, 172, 173; 271, 272, 273) of all the rolling stations (100, 200) is movable with respect to the load structure in order to disengage the respective roller (131, 132, 133; 231, 232, 233) and possibly release the box extraction path.

2. Rolling mill according to claim 1, wherein The single extensions (171, 172, 173; 271, 272, 273), when operatively connected to the respective roller (131, 132, 133; 231, 232, 233), are axially aligned with the rotation axis (R1, R2, R3) of the respective roller.

3. Rolling mill according to claim 1 or 2, wherein The single extension (171, 271) associated with the roller with vertical axis (131, 231) is arranged axially in the vertical direction and is associated with the respective gear motor group (161, 261); the angular gearbox (161b, 261b) has an input shaft and an output shaft forming a 90º angle therebetween, or has an input shaft and an output shaft parallel to each other.

4. Rolling mill according to claim 1 or 2, wherein The single extension (172, 173; 272, 273) associated with the roller with inclined axis (132, 133; 232, 233) is associated with the respective gear motor group (162, 163; 262, 263), in which the angular gearbox has an input shaft and an output shaft parallel to each other.

5. Rolling mill according to claim 1 or 2, wherein Each single extension (171, 172, 173; 271, 272, 273) of all the rolling stations (100, 200) is translatable along its axis with respect to the load structure in order to disengage the respective roller (131, 132, 133; 231, 232, 233) and release the associated roller-holder box for its extraction.

6. Rolling mill according to claim 5, wherein The single extensions (171, 172, 173; 271, 272, 273) are telescopic, the translational movement along the axis of the extension being obtained with the sliding movement of the relative telescopic structure.

7. The rolling mill according to claim 1 or 2, wherein The single extensions (171, 172, 173; 271, 272, 273) are slidable along the gearbox shaft of the respective gear motor group in order to disengage the hub of the respective roller.

8. The rolling mill according to claim 1 or 2, wherein In all the rolling stations (100, 200), at least one (172, 272) of the single extensions can perform a rotational translation movement to disengage the respective roll (132, 232) and release the respective roll-holder box to extract it.

9. The rolling mill according to claim 1 or 2, wherein The gear motor groups (161, 162, 163; 261, 262, 263) of all the rolling stations are fixedly mounted on the respective base.

10. The rolling mill according to claim 1 or 2, wherein Each of the three actuators (141, 142, 143; 241, 242, 243) comprises: - an adjustment element adapted to directly engage the respective roll; and - control means.

11. The rolling mill of claim 10, wherein, The actuators are completely mounted on the load-bearing structure (110, 210) of the respective roll-holder box (120, 220), both the control means and the adjustment element being mounted on the load-bearing structure (110, 210).

12. The rolling mill of claim 11, wherein, The actuators (141, 142, 143; 241, 242, 243) are hydraulic and the respective adjustment element consists of a piston (151, 152, 153; 251, 252, 253) movable along the radial axis (T1, T2, T3).

13. The rolling mill of claim 11, wherein, The actuators (141, 142, 143; 241, 242, 243) are mechanical and the respective adjustment element consists of an adjustment screw movable along the radial axis (T1, T2, T3).

14. The rolling mill of claim 10, wherein, The actuators are partially mounted on the load-bearing structure (110, 210) of the respective roll-holder box (120, 220), the control means being mounted on the load-bearing structure and the adjustment element being mounted on the respective roll-holder box.

15. The rolling mill of claim 14, wherein, The actuators (141, 142, 143; 241, 242, 243) are mechanical and the respective adjustment element consists of an adjustment screw movable along the radial axis (T1, T2, T3).

16. The rolling mill of claim 1 or 2, wherein, Each rolling station (100, 200) comprises movement means (300) for moving the respective roll-holder box along an extraction path.

17. The rolling mill of claim 16, wherein, The movement means (300) are placed on the side (1b) of the rolling mill (1) opposite the box extraction side (1a).

18. The rolling mill of claim 16, wherein, The movement means (300) consist of at least one hydraulic-pneumatic cylinder.

19. The rolling mill of claim 1 or 2, wherein, Each rolling station (100, 200) is equipped with a system for detecting the radial position of the respective roll, said system being mounted on the respective roll-holder box and being operatively connectable to the respective actuator.

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