Rolling mill stand with roll spacing adjustment system
The rolling mill stand with eccentric bushes and distance sensors addresses the challenge of inaccurate roll gap adjustment under load, ensuring precise and reliable roll gap adjustment, reducing wear and improving product accuracy.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- DANIELI & C OFFICINE MECCANICHE SPA
- Filing Date
- 2024-05-16
- Publication Date
- 2026-05-19
AI Technical Summary
Conventional roll gap adjustment systems in rolling mill stands cannot accurately adjust the distance between rolling rolls under a loaded state, leading to inaccuracies, wear, and inefficiencies in maintaining product tolerances.
A rolling mill stand equipped with eccentric bushes and distance sensors that allow for precise adjustment of the roll gap under load, using triangulation to determine the position of shafts and adjust the distance between rolling rolls.
Enables precise and reliable adjustment of the roll gap even during rolling, reducing wear and improving the accuracy of product dimensions while minimizing deformation and deflection.
Smart Images
Figure 2026516137000001_ABST
Abstract
Description
Technical Field
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[0001] The present invention relates to the field of rolling for manufacturing long steel semi-finished products such as steel bars and wire rods from billets.
[0002] In particular, the present invention relates to a rolling mill stand equipped with a system for adjusting the distance between rolling rolls, particularly a system having an eccentric bush. Furthermore, the present invention relates to a rolling device and method for adjusting the distance between rolling rolls.
Background Art
[0003] So-called "long" steel semi-finished products, such as steel bars and wire rods, are generally manufactured by a rolling device composed of a plurality of rolling mill stands arranged in sequence.
[0004] In this specification, the term "rolling" means hot rolling of steel products, which is either rough rolling or finish rolling performed within tolerances.
[0005] The size of the steel semi-finished product is substantially determined by the distance between the rolling rolls (also referred to as the rolling gap or working gap).
[0006] Some rolling mill stands may be equipped with a system for adjusting the distance between the rolling rolls.
[0007] Conventional roll gap adjustment systems cannot achieve optimal adjustment and have technical limitations.
[0008] In particular, in the current control system, it is not possible to adjust the rolling gap under a loaded state, that is, during rolling.
[0009] There are advantages that if the rolling gap can be adjusted under a loaded state, the wear of the rolling rolls can be compensated, the replacement time can be delayed, waste can be reduced while obtaining materials within tolerances, and the tolerances can be maintained.
[0010] A drawback is that, in currently known systems, the effect of adjusting the gap between the rolling rolls in the rolling mill stand is only apparent when rolling the next billet, because the adjustment is performed in billet-to-billet mode.
[0011] In fact, the adjustment system is not designed to verify whether the rolling rolls actually moved correctly during billet rolling.
[0012] This is particularly due to the inability to measure the rolling gap in real time, or to measure it accurately.
[0013] Furthermore, the adjustment mechanism is not structurally designed to allow adjustment under load. In fact, this mechanism contains areas with low bending and torsional rigidity, as well as sliding joints under high friction loads.
[0014] In addition to the low rigidity of this mechanism, the lack of feedback regarding the actual width of the rolling gap, which changes as the rolling grooves progressively wear down, leads to errors and ineffective or inaccurate adjustments.
[0015] Therefore, it is necessary to overcome the limitations of conventional technology. [Overview of the project]
[0016] The object of the present invention is to enable the adjustment of the distance between rolling rolls in a rolling mill stand of the type equipped with eccentric bushings for adjusting the distance between rolling rolls, particularly in a rolling mill stand of the type having a cantilever shaft, in a manner that is superior to the prior art and especially reliable.
[0017] In particular, an object of the present invention is to provide a rolling mill stand that can adjust the distance between rolling rolls under load, i.e., during rolling.
[0018] More specifically, the objective is to provide a rolling mill stand that can verify the distance between rolling rolls even under load.
[0019] Furthermore, an object of the present invention is to provide a rolling mill stand that increases the rigidity of the mechanism for adjusting the distance between rolling rolls, and in particular minimizes deformation and deflection of the structure that causes premature wear of the rolling mill stand and its components.
[0020] The present invention achieves at least these objectives, and other objectives evident herein, by the rolling mill stand described in claim 1.
[0021] In other words, a rolling mill stand for rolling steel semi-finished products, particularly long products, specifically steel materials, comprising at least one pair of rolling rolls, each of which is mounted on a corresponding shaft, Each shaft is inserted into a corresponding eccentric bushing, and each eccentric bushing is configured to rotate around its corresponding axis of rotation, allowing the distance between the rolling rolls to be adjusted by the rotation of the eccentric bushings. A rolling mill stand comprising at least two distance sensors corresponding to each shaft, wherein the distance sensors are configured to detect the distance between each sensor and the corresponding shaft, or the distance between each sensor and a body supporting the corresponding shaft.
[0022] The present invention further relates to the rolling apparatus described in claim 16.
[0023] The present invention further relates to the method described in claim 17.
[0024] In other words, a method for adjusting the distance between rolling rolls, i.e., the rolling gap, in a rolling mill stand, comprising a control circuit or electronic control unit connected to a sensor, wherein the adjustment of the distance between rolling rolls is performed based on distance values detected by the sensor, and in particular based on the position of each shaft relative to the rotation axis of the corresponding eccentric bush, which is determined by triangulation based on distance values detected by the distance sensor.
[0025] Advantageously, as will be described later, two distance sensors are provided corresponding to each of the shafts, and the values detected by these sensors are utilized by a control circuit or an electronic control unit to identify the position of the shafts, particularly the position of the corresponding eccentric bushes with respect to the rotation axes, by triangulation, and the distance between the rolls is determined based on the position of the shafts identified by triangulation. Therefore, advantageously, the rolling mill stand of the present invention can verify the actual distance between the rolling rolls, and thereby, even in a loaded state, the distance between the rolls can be adjusted more accurately and reliably.
[0026] Advantageously, the rolling mill stand adjusts the roll gap by means of eccentric bushes, so the reliability of the gap adjustment is particularly high and is superior, for example, to the adjustment by hydraulic cylinders. In fact, when using hydraulic cylinders, a synchronization error between the hydraulic cylinders may occur, which may cause an undesirable asymmetric movement of the rolls.
[0027] Therefore, due to the synergistic effect of the adjustment by eccentric bushes and the use of distance sensors that can identify the position of the shafts by triangulation and determine the width of the rolling gap, even in a loaded state, a more precise and reliable adjustment of the rolling gap is possible.
[0028] Preferably, in all embodiments, the rolling mill stand may have the features of claim 11 or 12. Advantageously, with this configuration, the mechanism for adjusting the distance between the rolling rolls has structurally higher rigidity, and thus, even in a loaded state, the distance between the rolling rolls can be adjusted particularly precisely and reliably without applying stress to the components.
[0029] Therefore, a synergistic effect is obtained by the combination of the use of distance sensors that can triangulate the position of the shafts to determine the width of the rolling gap and an adjustment mechanism having structurally higher rigidity. Due to this synergistic effect, particularly in a loaded state, the rolling gap can be adjusted more precisely and reliably.
[0030] Preferably, in all embodiments, the sensor is arranged such that the corresponding shaft is oriented in a direction orthogonal to the axis of rotation of the eccentric bush into which it is inserted.
[0031] The rolling mill stand of the present invention is suitable for rolling steel semi-finished products, particularly long steel semi-finished products such as wire rods and bars.
[0032] Further features and advantages of the present invention will become more apparent from the following detailed description of exemplary but non-limiting embodiments.
[0033] The dependent claims further specify particular embodiments of the present invention.
Brief Description of the Drawings
[0034] The description of the present invention is made with reference to the accompanying drawings as non-limiting examples.
[0035] [Figure 1] It is a schematic view of the rolling device of the present invention. [Figure 2] It is a perspective view showing a part of the rolling mill stand of the present invention, and only one rolling roll is shown for the purpose of explanation. [Figure 3] It is a perspective view showing a part of the rolling mill stand, and a part of the components is removed for comparison with FIG. 2 for the purpose of explanation. [Figure 4] It is a top view of a part of the rolling mill stand of the present invention in the first configuration. [Figure 5] It is a schematic top view of the components shown in FIG. 4 in the second configuration. [Figure 6] It is a perspective view showing a part of the rolling mill stand of the present invention. [Figure 7] It is a perspective view of the rolling mill stand with a part of the components removed for comparison with FIG. 6 for the purpose of explanation.
[0036] The same reference numerals are assigned to the same elements or components.
Embodiments for Carrying Out the Invention
[0037] With reference to the drawings, an embodiment of the rolling mill stand 1 of the present invention will be described in a non-limiting manner.
[0038] The rolling mill stand 1 is particularly suitable for rolling steel semi-finished products, especially long steel semi-finished products, particularly for rough rolling or finish rolling processes. For example, the rolling mill stand 1 is particularly suitable for processing wire rods or steel bars.
[0039] The rolling mill stand 1 of the present invention is suitable for rolling virtually any long steel semi-finished product.
[0040] Rolling is carried out along the rolling axis R.
[0041] In all embodiments, the rolling mill stand 1 has at least one pair of rolling rolls 2a, 2b. Each of the rolling rolls 2a, 2b is mounted (directly or indirectly via ring bearing elements) to a corresponding shaft 3a, 3b. Each of the shafts 3a, 3b is inserted (directly or indirectly via bushings) into a corresponding eccentric bush 4a, 4b. Each of the eccentric bush 4a, 4b is configured to rotate around a corresponding rotation axis A, B. The rotation of the eccentric bush 4a, 4b is performed by an actuation system connected to the eccentric bush 4a, 4b directly or indirectly, thereby adjusting the distance G1, G2 between the rolling rolls 2a, 2b. Advantageously, the rolling mill stand 1 also has at least two distance sensors 51a, 52a, 51b, 52b corresponding to each of the shafts 3a, 3b. These are configured to detect (or measure) distances c1, c2, c3, c4, d1, d2, d3, d4 between each of the sensors 51a, 52a, 51b, 52b and the corresponding shafts 3a, 3b (particularly preferred embodiment). In particular, they detect (or measure) distances between each of the sensors 51a, 52a, 51b, 52b and the corresponding outer surfaces 30a, 30b of the shafts 3a, 3b. Alternatively, at least two distance sensors 51a, 52a, 51b, 52b corresponding to each of the shafts 3a, 3b are configured to detect distances between each of the sensors 51a, 52a, 51b, 52b and a body, particularly a tubular body, that supports the corresponding shafts 3a, 3b. The body is preferably an eccentric bush 4a, 4b, or another member that supports the corresponding shafts 3a, 3b, particularly into which the corresponding shafts 3a, 3b are inserted.
[0042] The aforementioned outer surfaces 30a and 30b are, in particular, outer surfaces extending around the longitudinal axes X and Y of the corresponding shafts 3a and 3b. Specifically, the outer surfaces 30a and 30b are cylindrical. Preferably, the outer surfaces 30a and 30b are surfaces that define the maximum diameter of the shafts 3a and 3b (or the main body). Therefore, the sensors 51a, 52a, 51b, and 52b are as close as possible to the corresponding shafts 3a and 3b or the main body.
[0043] Advantageously, the two distance sensors 51a, 52a, 51b, and 52b are provided corresponding to shafts 3a and 3b, respectively. This allows a control circuit (not shown) or an electronic control unit to use the values detected by sensors 51a, 52a, 51b, and 52b to triangulate the positions of shafts 3a and 3b, particularly the positions of the corresponding eccentric bushes 4a and 4b relative to the rotation axes A and B. Based on the positions of shafts 3a and 3b determined by triangulation, the distances G1 and G2 between the rolling rolls 2a and 2b are then determined.
[0044] Sensors 51a, 52a, 51b, and 52b are positioned to measure distances c1, c2, c3, c4, d1, d2, d3, and d4 between them and the corresponding shafts 3a and 3b (or the bodies supporting the aforementioned corresponding shafts 3a and 3b). This allows for more accurate measurements than measuring the distance between the sensor and the rolling roll (in fact, many sensors, such as inductive sensors, have higher accuracy in short-distance measurements). Furthermore, the rolls are susceptible to wear and damage. Also, with the arrangement of sensors 51a, 52a, 51b, and 52b of the present invention, they are further away from the rolling axis R, thus reducing the risk of damage, contamination, and exposure to the coolant.
[0045] Each of the sensors 51a, 52a, 51b, and 52b measures the distances c1, c2, c3, c4, d1, d2, d3, and d4 to the corresponding shafts 3a and 3b (or the main body mentioned above) along an axis perpendicular to the longitudinal axes X and Y of the corresponding shafts 3a and 3b, more specifically along the radial direction.
[0046] The eccentric bushings 4a and 4b are housed within a structure 61 configured to be rotatable around their corresponding axes A and B.
[0047] Figures 2 and 3 show the axes of rotation A and B on which the eccentric bushings 4a and 4b rotate. Each of the shafts 3a and 3b is inserted into the corresponding eccentric bushings 4a and 4b. The longitudinal axes X and Y of the shafts 3a and 3b are spaced apart from and parallel to the axes of rotation A and B of the eccentric bushings 4a and 4b into which the shafts 3a and 3b are inserted.
[0048] When the eccentric bushings 4a and 4b rotate around their corresponding axes A and B, the shafts 3a and 3b move apart or closer together. Therefore, to adjust the distances G1 and G2 between the rolling rolls 2a and 2b (Figures 4 and 5), the rolling rolls 2a and 2b should be rotated around their corresponding axes A and B.
[0049] During rolling, the rolls 2a and 2b rotate around the longitudinal axes X and Y of the corresponding shafts 3a and 3b.
[0050] Figure 4 shows the initial configuration of the rolling mill stand 1. The distance between rolls 2a and 2b is indicated by the symbol G1. Figure 5 shows the second configuration of the rolling mill stand 1. The distance between rolls 2a and 2b is indicated by the symbol G2. Distance G1 is greater than distance G2. For example, distance G1 is the maximum distance between rolls 2a and 2b, and distance G2 is the minimum distance between rolls 2a and 2b.
[0051] The distances between sensors 51a, 52a, 51b, and 52b and their corresponding shafts 3a and 3b are roughly shown by thick lines and are denoted by symbols c1, c2, c3, c4, d1, d2, d3, and d4.
[0052] In particular, in the first configuration, the distance between sensor 51a and shaft 3a is denoted by symbol c1, the distance between sensor 52a and shaft 3a is denoted by symbol c2, the distance between sensor 51b and shaft 3b is denoted by symbol d1, and the distance between sensor 52b and shaft 3b is denoted by symbol d2.
[0053] In the second configuration, the distance between sensor 51a and shaft 3a is denoted by the symbol c3, the distance between sensor 52a and shaft 3a is denoted by the symbol c4, the distance between sensor 51b and shaft 3b is denoted by the symbol d3, and the distance between sensor 52b and shaft 3b is denoted by the symbol d4.
[0054] The sensors 51a, 52a, 51b, and 52b are fixed to the structure 61, either directly or indirectly via additional elements, and are positioned particularly stably. In particular, in all embodiments, the sensors 51a, 52a, 51b, and 52b are integrated with the structure 61.
[0055] Preferably, the sensors 51a, 52a, 51b, and 52b are fixed to a surface 611 of the structure 61 adjacent to the rolling rolls 2a and 2b. This is advantageous as it allows workers easy access to them, for example, to replace or repair them during maintenance processes. The surface 611 is particularly the surface from which the shafts 3a and 3b protrude.
[0056] In all embodiments, preferably, at least two sensors 51a, 52a, 51b, 52b corresponding to each of the shafts 3a, 3b are positioned between the structure 61 and the rolling rolls 2a, 2b, particularly below the rolling rolls 2a, 2b.
[0057] Preferably, at least two sensors 51a, 52a, 51b, and 52b corresponding to each of the shafts 3a and 3b are positioned between the corresponding eccentric bushings 4a and 4b and the corresponding rolls 2a and 2b.
[0058] At least two sensors 51a, 52a, 51b, and 52b, corresponding to each of the shafts 3a and 3b, are positioned, in particular, toward the outer circumferential surfaces 30a and 30b of the corresponding shafts 3a and 3b, or toward the outer circumferential surfaces 30a and 30b of the body supporting the corresponding shafts.
[0059] Preferably, the sensors 51a, 52a, 51b, and 52b are covered by a flange 62 or a plate, which advantageously protects the sensors 51a, 52a, 51b, and 52b.
[0060] The flange 62 is fixed to the structure 61, either directly or via additional elements. In particular, the flange 62 has two through holes, through which the corresponding shafts 3a and 3b pass. The flange 62 is detachable from the structure 61, thereby providing access to the sensors 51a, 52a, 51b, and 52b.
[0061] Sensors 51a, 52a, 51b, and 52b are preferably inductive sensors, particularly eddy current inductive proximity sensors. Inductive sensors are particularly advantageous because they operate in contaminated environments, especially contaminated environments containing water or steam.
[0062] Alternatively, other types of distance sensors, such as capacitive, laser, or touch probe sensors, may be used.
[0063] Preferably, each of the sensors 51a, 52a, 51b, and 52b is positioned at a distance of 0.5 to 100 mm, more preferably 0.5 to 15 mm, from the corresponding shafts 3a, 3b (or the body supporting the corresponding shafts).
[0064] Preferably, at least two sensors 51a, 52a, 51b, and 52b corresponding to shafts 3a and 3b are arranged on the same circumference. However, they can also be arranged at different distances from the corresponding shafts 3a and 3b.
[0065] The number of sensors 51a, 52a, 51b, and 52b corresponding to shafts 3a and 3b may be two or more. Increasing the number of sensors enables more accurate triangulation.
[0066] The rolling mill stand 1 preferably has a control circuit or an electronic control unit. The control circuit or electronic control unit is configured to determine the distances G1 and G2 between the rolls 2a and 2b, i.e., the rolling gap, based on the distance values c1, c2, c3, c4, d1, d2, d3, and d4 detected by the sensors 51a, 52a, 51b, and 52b.
[0067] In particular, the control circuit is preferably configured to determine the positions of shafts 3a and 3b, especially the positions of the corresponding eccentric bushings 4a and 4b with respect to the rotation axes A and B, by triangulation, and to determine the distances G1 and G2 between the rolling rolls 2a and 2b based on the triangulation. The triangulation is performed based on the distance values c1, c2, c3, c4, d1, d2, d3, and d4 detected by sensors 51a, 52a, 51b, and 52b.
[0068] Particularly preferably, the control circuit or electronic control unit is configured to adjust the distance G1, G2 between the rolling rolls 2a, 2b, i.e., the rolling gap. This adjustment is made based on distance values c1, c2, c3, c4, d1, d2, d3, d4, in particular, detected by sensors 51a, 52a, 51b, 52b. More specifically, this adjustment is made based on the positions of shafts 3a, 3b, respectively, as determined by triangulation.
[0069] Triangulation can be performed in various ways. Preferably, for triangulation to be performed, sensors 51a, 52a, 51b, and 52b are positioned perpendicular to the rotation axes A and B of eccentric bushes 4a and 4b into which the corresponding shafts 3a and 3b are inserted. It is preferable that sensors 51a, 52a, 51b, and 52b are housed in a dedicated housing or fixed cavity.
[0070] For example, when the corresponding shafts 3a and 3b, or more specifically the outer surfaces 30a and 30b of the corresponding shafts 3a and 3b, enter the field of view (or operating area) of sensors 51a, 52a, 51b, and 52b, the sensors detect distance values c1, c2, c3, c4, d1, d2, d3, and d4 between a point on the outer surface 30a and 30b and sensors 51a, 52a, 51b, and 52b.
[0071] According to the well-known equation of a circle, a point lies on the circumference only if its distance from the center is equal to the radius. By measuring the positions of at least two points and knowing the radius values (design values) of shafts 3a and 3b, the position on the circumference can be monitored over time. This makes it possible to determine the positions of shafts 3a and 3b themselves in relation to each other.
[0072] There may be some play, for example, of about 0.15 mm, between the shafts 3a and 3b and their corresponding eccentric bushings 4a and 4b, or in the position of the sensors 51a, 52a, 51b, and 52b within the corresponding housings. Therefore, periodic readjustment of the position can ensure the accuracy of the measurements over time.
[0073] Specifically, calibration can be performed by, for example, setting the gap between rolls 2a and 2b to zero (or to the minimum value allowed by the rolling mill stand) and measuring the corresponding distances c1, c2, c3, c4, d1, d2, d3, and d4, and then gradually widening the gap to the maximum value allowed by the rolling mill stand and recording the distances c1, c2, c3, c4, d1, d2, d3, and d4 at each intermediate position.
[0074] If necessary, to further enhance the reliability of the measurements, the accuracy of the measurements at intermediate positions can be verified by inserting a specific mechanical reference object into the gap between rolls 2a and 2b and checking for any accidental positional shifts that may occur over time.
[0075] The aforementioned adjustment of the distances G1 and G2 between the rolling rolls 2a and 2b, i.e., the rolling gap, can be performed under load, i.e., during rolling, or in other words, as an online adjustment.
[0076] In all embodiments, each of the shafts 3a and 3b is preferably cantilevered. In particular, each of the shafts 3a and 3b is cantilevered to the structure 61. That is, both shafts 3a and 3b are cantilevered to the same structure 61.
[0077] In effect, the rolling rolls 2a and 2b are cantilevered.
[0078] The cantilevered shafts 3a and 3b have several advantages, including particularly easy access to the rolling rolls 2a and 2b.
[0079] In particular, shafts 3a and 3b are supported on only one side.
[0080] Specifically, shafts 3a and 3b each protrude from the structure 61. More specifically, shafts 3a and 3b each have an end that protrudes from the structure 61.
[0081] Each of the rolls 2a and 2b is attached to the end of the corresponding shaft 3a and 3b. These ends are the parts that protrude from the structure 61.
[0082] The longitudinal axes X and Y of shafts 3a and 3b are spaced apart from and parallel to each other.
[0083] Preferably, each rolling mill stand 1 is equipped with two rolls. As an example, a rolling line for long products may consist of 20 or more rolling mill stands 1. A finishing device or finishing unit may consist of up to 12 units, for example, 4 to 8 rolling mill stands 1.
[0084] The rolling mill stand 1 has a mechanism for adjusting the distances G1 and G2 between the rolling rolls 2a and 2b. As shown in Figures 6 and 7, the distance adjustment mechanism preferably has a worm screw 71. The worm screw 71 is connected to eccentric bushes 4a and 4b via corresponding nut screws 72a and 72b and corresponding arms 73a, 74a, 73b, and 74b. Each of the arms is hinged to the corresponding nut screws 72a and 72b and the corresponding eccentric bushes 4a and 4b. The rotation of the worm screw 71 displaces the nut screws 72a and 72b along the worm screw 71, thereby causing the eccentric bushes 4a and 4b to rotate around their corresponding axes A and B.
[0085] In particular, the worm screw 71 is positioned perpendicular to the shafts 3a and 3b, or more precisely, perpendicular to the longitudinal axes X and Y of the shafts 3a and 3b.
[0086] Each of the eccentric bushes 4a and 4b is preferably connected to the corresponding nut screws 72a and 72b via two corresponding arms 73a, 74a, 73b, and 74b. Preferably, a pin 75a passes through the arm 73a and nut screw 72a, connecting them to each other. A pin 76a passes through the arm 74a and nut screw 72a, connecting them to each other. A pin 75b passes through the arm 73b and nut screw 72b, connecting them to each other. A pin 76b passes through the arm 74b and nut screw 72b, connecting them to each other. However, pins 75a and 76a can be a single component. That is, a single pin can connect the nut screw 72a to the two arms 73a and 74a to each other. Similarly, pins 75b and 76b can be a single component. That is, a single pin can connect the nut screw 72b to the two arms 73b and 74b to each other.
[0087] The remaining pins connect the eccentric bushings 4a and 4b to their respective arms 73a, 74a, 73b, and 74b.
[0088] Preferably, two sliding guides 77, 78 (or grooves) are provided. Pins 75a, 76a, 75b, 76b, which connect the arms 73a, 74a, 73b, 74b to their corresponding nut screws 72a, 72b, are partially fitted into the corresponding sliding guides 77, 78. Therefore, preferably, at least a portion of the force acting on the worm screw 71 is distributed to the sliding guides 77, 78.
[0089] Preferably, both the torsional stress generated when the worm screw 71 rotates around its longitudinal axis and the force that attempts to bend the worm screw 71 due to the strain of the rolled material during rolling are distributed to the sliding guides 77 and 78.
[0090] Pins 75a and 75b, particularly their ends, are partially fitted into the sliding guide 77. Pins 76a and 76b, particularly their ends, are partially fitted into the sliding guide 78. The sliding guide 78 is positioned further out, i.e., further away from the rolling rolls 2a and 2b, while the sliding guide 77 is positioned further in.
[0091] Preferably, the ends of each pin 75a, 76a, 75b, and 76b fitted into the respective sliding guides 77 and 78 have two flat surfaces. This allows the forces acting on the corresponding sliding guides 77 and 78 to be more effectively relieved.
[0092] The sliding guides 77 and 78 are positioned parallel to the worm screw 71. The worm screw 71 extends along the two sliding guides 77 and 78.
[0093] Two sliding guides 77 and 78 are fixed to each other by two members 79a and 79b that are perpendicular to them in particular. A worm screw 71 passes through member 79a, and preferably through member 79b as well. The end 711 of the worm screw 71 protruding from member 79b is configured to be connected to an actuator (not shown) that rotates the worm screw 71 about its longitudinal axis. Preferably, the end of the worm screw 71 opposite to the end 711 also protrudes from member 79a and is similarly configured to be connected to an actuator that rotates the worm screw 71 about its longitudinal axis.
[0094] As the worm screw 71 rotates around its longitudinal axis, the pins 75a, 76a, 75b, and 76b move in conjunction with their corresponding nut screws 72a and 72b, respectively, along their corresponding sliding guides 77 and 78.
[0095] The sliding guides 77 and 78 are configured to guide the sliding of the pins 75a, 76a, 75b, and 76b in a direction perpendicular to the rotation axes A and B of the eccentric bushes 4a and 4b.
[0096] The two sliding guides 77, 78 and members 79a, 79b are fixed particularly rigidly to the structure 61 in which the eccentric bushes 4a, 4b are housed.
[0097] The present invention further relates to a method for adjusting the distances G1 and G2 between the rolling rolls 2a and 2b of a rolling mill stand 1, i.e., the rolling gap. A control circuit (or electronic control unit) is connected to sensors 51a, 52a, 51b, and 52b. The adjustment of the distances G1 and G2 between the rolling rolls 2a and 2b is performed based on distance values c1, c2, c3, c4, d1, d2, d3, and d4 detected by sensors 51a, 52a, 51b, and 52b. In particular, the distances G1 and G2 are adjusted based on the respective positions of shafts 3a and 3b, which are determined by triangulation. In particular, triangulation based on distance values c1, c2, c3, c4, d1, d2, d3, and d4 detected by distance sensors 51a, 52a, 51b, and 52b determines the respective positions of shafts 3a and 3b relative to the rotation axes A and B of the corresponding eccentric bushes 4a and 4b, and distances G1 and G2 are adjusted based on these positions.
[0098] In particular, the control circuit can be connected to a user interface. Through this user interface, the desired distance between the rolling rolls 2a and 2b can be set. Before and / or after the distance between the rolling rolls 2a and 2b is set, the actual distances G1 and G2 between the rolling rolls 2a and 2b can be verified by triangulation of the positions of the shafts 3a and 3b. That is, feedback regarding the actual distances G1 and G2 between the rolling rolls 2a and 2b can be obtained by triangulation. Preferably, means for detecting the size of the rolled product are also provided, thereby providing additional feedback.
[0099] The present invention further relates to a rolling mill 100 having at least one rolling mill stand 1. Optionally, the rolling mill 100 may have a plurality of rolling mill stands 1 arranged sequentially along a rolling axis R. That is, the rolling mill 100 is a rolling train. Preferably, the rolling mill stands 1 are arranged sequentially such that the rotation axes of the rolls of the consecutive rolling mill stands are perpendicular to each other.
[0100] Preferably, the rolling train is used to perform the finish rolling process.
Claims
1. A rolling mill stand (1) for rolling steel semi-finished products, particularly for obtaining long products, It comprises at least one pair of rolling rolls (2a, 2b), each of which is attached to a corresponding shaft (3a, 3b). The shafts (3a, 3b) are each inserted into corresponding eccentric bushings (4a, 4b), and the eccentric bushings are configured to rotate around their respective rotation axes (A, B), and the distance (G1, G2) between the rolling rolls (2a, 2b) can be adjusted by the rotation of the eccentric bushings (4a, 4b). The rolling mill stand (1) is equipped with at least two distance sensors (51a, 52a, 51b, 52b) corresponding to each of the shafts (3a, 3b), and the distance sensors are configured to detect the distance (c1, c2, c3, c4, d1, d2, d3, d4) between each of the distance sensors (51a, 52a, 51b, 52b) and the corresponding shafts (3a, 3b), or between each of the distance sensors (51a, 52a, 51b, 52b) and the main body supporting the corresponding shafts (3a, 3b). Rolling mill stand (1).
2. The eccentric bushings (4a, 4b) are housed within the structure (61) and are configured to be rotatable relative to the structure. The rolling mill stand (1) according to claim 1.
3. The distance sensors (51a, 52a, 51b, 52b) are fixed to the structure (61) in particular, either directly or via additional elements, and in particular, the distance sensors (51a, 52a, 51b, 52b) are integrated with the structure (61). The rolling mill stand (1) according to claim 2.
4. Each of the shafts (3a, 3b) is cantilevered, and in particular each of the shafts (3a, 3b) is cantilevered with respect to the structure (61), and in particular each of the shafts (3a, 3b) protrudes from the structure (61). A rolling mill stand (1) according to any one of claims 1 to 3.
5. Each of the rolling rolls (2a, 2b) is attached to the corresponding end of the shaft (3a, 3b), and the end protrudes from the structure (61). A rolling mill stand (1) according to any one of claims 2 to 4.
6. The longitudinal axes (X, Y) of the aforementioned shafts (3a, 3b) are spaced apart from each other and parallel to each other. A rolling mill stand (1) according to any one of claims 1 to 5.
7. The distance sensors (51a, 52a, 51b, 52b) are covered by flanges (62) or plates fixed to the structure (61) in particular, either directly or via additional elements, the flanges (62) or plates having two through holes, through which the shafts (3a, 3b) corresponding to each of the through holes pass. A rolling mill stand (1) according to any one of claims 2 to 6.
8. The distance sensors (51a, 52a, 51b, 52b) are fixed to the surface (611) of the structure (61) that is close to the rolls (2a, 2b). A rolling mill stand (1) according to any one of claims 2 to 7.
9. At least two of the distance sensors (51a, 52a, 51b, 52b) corresponding to each of the shafts (3a, 3b) are arranged on the same circumference, and / or each of the distance sensors (51a, 52a, 51b, 52b) is positioned at a distance of 0.5 to 100 mm, preferably 0.5 to 15 mm, from the corresponding shaft (3a, 3b) or the main body. A rolling mill stand (1) according to any one of claims 1 to 8.
10. The circuit includes a control circuit or electronic control unit configured to determine the distance (G1, G2) between the rolling rolls (2a, 2b), i.e., the rolling gap, based on the distance values (c1, c2, c3, c4, d1, d2, d3, d4) detected by the distance sensors (51a, 52a, 51b, 52b). Preferably, the control circuit is configured to determine the distance (G1, G2) between the rolling rolls (2a, 2b), i.e., the rolling gap, by triangulation, particularly by identifying the positions of the shafts (3a, 3b) with respect to the rotation axes (A, B) of the corresponding eccentric bushes (4a, 4b), based on the distance values (c1, c2, c3, c4, d1, d2, d3, d4) detected by the distance sensors (51a, 52a, 51b, 52b). A rolling mill stand (1) according to any one of claims 1 to 9.
11. The rolling mill is equipped with a mechanism for adjusting the distance (G1, G2) between the rolling rolls (2a, 2b), the mechanism having a worm screw (71), the worm screw being connected to the eccentric bushes (4a, 4b) via corresponding nut screws (72a, 72b) and corresponding arms (73a, 74a, 73b, 74b), each of the arms being hinged to the corresponding nut screws (72a, 72b) and corresponding eccentric bushes (4a, 4b), the rotation of the worm screw (71) displaces the nut screws (72a, 72b) along the worm screw (71), thereby causing the eccentric bushes (4a, 4b) to rotate. Two sliding guides (77, 78) are provided, and the pins (75a, 76a, 75b, 76b) that connect each of the arms (73a, 74a, 73b, 74b) to the corresponding nut screws (72a, 72b) are partially fitted into the corresponding sliding guides (77, 78) of the two sliding guides (77, 78). A rolling mill stand (1) according to any one of claims 1 to 10.
12. The sliding guides (77, 78) are fixed to the structure (61) which houses the eccentric bushings (4a, 4b) and on which the eccentric bushings (4a, 4b) are rotatably mounted. The rolling mill stand (1) according to claim 11.
13. The main body has an outer circumferential surface extending around the longitudinal axis (X, Y) of the corresponding shaft (3a, 3b), and the outer circumferential surface is particularly cylindrical. A rolling mill stand (1) according to any one of claims 1 to 12.
14. The main body is the eccentric bush (4a, 4b), and in particular, at least two of the distance sensors (51a, 52a, 51b, 52b) corresponding to each of the shafts (3a, 3b) are configured to detect the distance (c1, c2, c3, c4, d1, d2, d3, d4) between each of the distance sensors (51a, 52a, 51b, 52b) and the corresponding eccentric bush (4a, 4b) supporting the shaft (3a, 3b). A rolling mill stand (1) according to any one of claims 1 to 13.
15. At least two of the distance sensors (51a, 52a, 51b, 52b) corresponding to each of the shafts (3a, 3b) are configured to detect the distance (c1, c2, c3, c4, d1, d2, d3, d4) between each of the distance sensors (51a, 52a, 51b, 52b) and the corresponding shaft (3a, 3b). A rolling mill stand (1) according to any one of claims 1 to 12.
16. The invention comprises at least one rolling mill stand (1) according to any one of claims 1 to 15, preferably at least one of the rolling mill stands (1) being a finishing rolling mill stand. Rolling mill equipment (100).
17. A method for adjusting the distance (G1, G2) between the rolling rolls (2a, 2b), i.e., the rolling gap, in a rolling mill stand (1) according to any one of claims 1 to 15, A control circuit or electronic control unit is provided connected to the distance sensors (51a, 52a, 51b, 52b), and the distance between the rolling rolls (2a, 2b) is adjusted based on the distance values (c1, c2, c3, c4, d1, d2, d3, d4) detected by the sensors (51a, 52a, 51b, 52b), and in particular based on the respective positions of the shafts (3a, 3b) identified by triangulation, and in particular based on the respective positions of the shafts (3a, 3b) relative to the rotation axes (A, B) of the corresponding eccentric bushes (4a, 4b) identified by triangulation based on the distance values (c1, c2, c3, c4, d1, d2, d3, d4) detected by the distance sensors (51a, 52a, 51b, 52b). method.