Cross rolling unit and method for setting rolling passes of the cross rolling unit

Abstract

A cross rolling unit having at least two rolls and a roll housing, in which at least one of the rolls is mounted, whereby its position can be adjusted to vary the rolling pass, and a method for setting the rolling pass of a cross rolling unit, enable the rolling pass to be adjusted even during rolling by a roll positioning device, which is characterized by a part connected to the housing and a part connected to the roller mill, which part can be moved relative to the part connected to the housing during rolling, and which parts can be repositioned relative to each other and / or the roll positioning device is characterized by a drive dimensioned to allow a rolling force to be applied.

Description

[Technical Field]

[0001] The present invention relates to a cross rolling unit and a method for setting the rolling passes of a rolling unit. [Background technology]

[0002] Such a cross rolling unit and setting method are known, for example, from EP 2 116 312 A1. Here, the cross rolling unit comprises at least two rolls, each mounted on a roller mill, and a roll housing. At least one of the roller mills is mounted in the roll housing, the position of which can be adjusted via roller mill setting means, here an eccentric bushing, to change the rolling path, here the feed. JP 53-149858 A also discloses a corresponding cross rolling unit. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] European Patent Application Publication No. 2116312 [Patent Document 2] Japanese Patent Publication No. 53-149858 Summary of the Invention [Problem to be solved by the invention]

[0004] The aim of the present invention is to provide a cross rolling unit and a method for setting the rolling passes of the cross rolling unit, which allows the best possible rolling result to be achieved. [Means for solving the problem]

[0005] The object of the present invention is achieved by a cross rolling unit and a method for setting a rolling pass of a cross rolling unit with the features of the independent claims. Further, or independently, advantageous configurations can be found in the dependent claims and in the following description.

[0006] The invention is based on the fundamental knowledge that good rolling results can be achieved if the rolling passes can be adjusted during rolling. In this way, the rolling passes can be adjusted accordingly to changes in the rolling parameters, which can be obtained for example by suitable measurements.

[0007] The cross rolling unit comprises at least two rolls and a roll housing in which at least one of the rolls is mounted so that the roll position can be set to vary the rolling pass, which makes it possible to set the rolls with a specific rolling pass.

[0008] In particular, in each case, both rolls, or if more rolls and associated roller mills are used, all of the roller mills in the two rolls, can be mounted so that their position can be set via the roller mill adjustment means for varying the rolling path, which allows for more precise adjustment or alignment of the rolling path.

[0009] In order to provide a cross rolling unit capable of achieving the best possible rolling results, and in implementation of the above-mentioned basic knowledge, a cross rolling unit having at least two rolls and a roll housing in which at least one of the rolls is mounted so that its position can be set to vary the rolling path, can be characterized in that the roll positioning device comprises a part connected to the housing and a part connected to the roller mill which can be moved relative to this part during rolling, and which parts are adjustable relative to each other.

[0010] The first part of the roll positioning device is preferably fixed to the housing, and the second part is connected to the roller mill. The housing, and therefore the first part of the roll positioning device, can remain stationary in the same position during rolling or, if necessary, can circulate through a fixed path during rolling. The roller mill, and therefore the second part of the roll positioning device connected to the roller mill, can also be adjusted relative to the first part or the roll housing. Here, the housing preferably remains in its position, and, if necessary, its circulating path, and the roller mill adapts accordingly. Here, adjustments can be made particularly during rolling, and parts of the roll positioning device can also adapt under load. In this way, the rolling path can be adapted during rolling, for example, to changes in the diameter of the workpiece or to appropriately react to changes in the workpiece's outer shape or to rolling parameters that change during rolling, such as during the infeed or unfeed process. For example, if the eccentricity of the workpiece is not constant, the rolling path can be individually adapted to the shape of the part to be rolled during rolling.

[0011] Furthermore, in order to provide a cross rolling unit capable of achieving the best possible rolling results, a cross rolling unit having at least two rolls and a roll housing in which at least one of the rolls is mounted so that its position can be set to vary the rolling path can be characterized in that the drives of the roll positioning devices are dimensioned in such a way that a rolling force can be applied.

[0012] If the roll positioning device is dimensioned to be able to apply a rolling force, the roll positioning device can also change its setting during rolling, thus positioning at least one of the rolls differently, which in turn allows the rolling pass to be changed during rolling.

[0013] Additionally or alternatively, in order to provide a cross rolling unit capable of achieving the best possible rolling results, a cross rolling unit having at least two rolls and a roll housing, at least one of the rolls being mounted so that its position can be set to vary the rolling pass, can be characterized in that a mandrel position adjusting device allows the mandrel position of the mandrel to be adjusted parallel to the workpiece during rolling. A preferred specific implementation results in the ability to adjust or adapt the rolling pass during rolling, according to the basic knowledge explained above.

[0014] As a result, for example, the position of the mandrel relative to the rolls, and thereby the effect of the rolling force on the workpiece or mandrel, can also be changed and the rolling pass can be influenced accordingly. For example, the mandrel can be adjusted to the same speed as the workpiece being rolled, so that the drilling of the workpiece only reaches a point where the mandrel does not conform to the same speed and direction as the workpiece. Furthermore, the workpiece may not be completely drilled, or the mandrel may be more easily removed from the workpiece after rolling. The above advantages are particularly enhanced by the fact that the mandrel can be adjusted parallel to the workpiece by the mandrel position adjustment device during rolling.

[0015] Additionally, by adjusting the mandrel positioning device, the divergence angle etc. and therefore the rolling pass can also be changed by the mandrel positioning device, for example if the latter is arranged perpendicular to the rolling axis as a mandrel holder, along the rolling axis spaced apart from the rolls. This can also be done by suitable settings or adjustment of the rolls, as described above. However, the former allows the rolling pass to be changed independently of the direction of movement of the roller mill or the part of the roll positioning device connected to the roller mill, or independently of the direction of movement of the roll positioning device itself, thereby providing a more cost-effective possibility of setting the rolling pass.

[0016] In particular, it is advantageous if the roll positioning device comprises at least one hydraulic cylinder, which, with efficient power and suitable design, allows in particular a fast setting of each roll.

[0017] It is particularly advantageous if hydraulic cylinders are used that allow high pressure or high travel speeds. This makes it possible, in particular, for each hydraulic cylinder to withstand at least part of the rolling force or to change the rolling path during rolling. In particular, if the corresponding hydraulic cylinders can be operated at a pressure of preferably 50,0000 hPa, the rolling force can be applied by the roll positioning device. For example, if the hydraulic cylinders can be moved faster than 30 mm / s, preferably faster than 35 mm / s, and / or can be activated using high-speed valves, sufficiently rapid adjustment possibilities can be ensured.

[0018] Depending on the particular implementation, it may be sufficient if the hydraulic cylinder stroke height is less than 150 mm. Depending on the particular implementation, even a stroke height of less than 100 mm may provide satisfactory results. If necessary, a two-stage system may be provided, in which the rolling pass is preselected using a coarse roll positioning device, and then adjustments during rolling may be made via a finer roll positioning device, e.g., with a small stroke, a high adjustment speed, and / or high pressure.

[0019] Preferably, two or more roll positioning devices are provided for at least one, several or all of the rolls. This allows for a more precise setting of the corresponding rolls, and, if necessary, their angles. Furthermore, the rolling force can be distributed over several roll positioning devices, which can be implemented in a correspondingly simpler manner from a constructional point of view.

[0020] It is advantageous if the cross rolling unit is equipped with a multivariable control system including at least two input variables and at least one output variable, both of which can be determined by or sent to the roll positioning device. The input variables can consist of measured variables, which can be determined, for example, by the roll positioning device or by other measurement systems and sent to the roll positioning device. This allows control actions to be performed based on the measured data, so that the cross rolling unit or the associated control system can intervene appropriately in the rolling process.

[0021] The measured variables determined by the roll positioning device are available to the cross rolling unit in a relatively simple manner, whereby in particular the rolling force and also the position of the rolls and roller mills will be mentioned as suitable measured variables.

[0022] Additionally or alternatively, the measured variables, in particular workpiece feed rate, workpiece discharge rate, wall thickness, eccentricity, outer diameter, ovality, rolling force, and mandrel holding force, can be recorded as input variables which are then additionally or alternatively used for multivariable control.

[0023] In this respect, a multivariable control with at least two input variables and at least one output variable is advantageous, since it allows the rolling process to be monitored more accurately and adapted accordingly. It will be appreciated that this advantage can be further enhanced by additional input and output variables. On the other hand, it is also conceivable that only one variable and / or only one output variable may be used, if this proves sufficient for a particular application.

[0024] The workpiece infeed rate represents the speed of the workpiece relative to the rolls before rolling. Depending on the workpiece infeed rate, the necessary or advantageous rolling passes can also vary. Furthermore, the size of the workpiece may be important, for example, in determining what workpiece infeed rates are possible. Additionally, if the mandrel is to be adjusted to a specific speed ratio to the workpiece, this rate may be a variable that needs to be controlled. It should be understood that, since blocks or hollow blocks may be used as workpieces and then passed through the cross rolling unit with or without holes, the infeed rate of the blocks or hollow blocks can serve as a measured variable.

[0025] On the other hand, the workpiece discharge speed refers to the speed of the workpiece relative to the rolls after rolling, after drilling, or while the workpiece is being removed or fed. The discharge speed of a hollow block is often faster than the infeed speed of the block because rolling frequently moves material in the direction of workpiece movement. However, the discharge speed of the workpiece may also be faster than the infeed speed of the workpiece during drilling or other rolling processes, especially in the case of expansion processes.

[0026] If desired, the difference between the infeed and outfeed rates of the workpiece can be advantageously used as a measured coefficient or a variable derived therefrom, since under certain circumstances this variable can also provide important information about the rolling process.

[0027] In particular in the case of cross rolling, the rotational speed of the workpiece, differentiated on the inlet and / or outlet side as required, can serve as a measured variable, since information about the rolling process can also be obtained therefrom.

[0028] The position of the workpiece, such as the length of the workpiece already rolled or the length of the workpiece yet to be rolled, can be a suitable measured variable to optimize the rolling process in a targeted manner, thereby providing, for example, different manipulated variable values ​​at the start of rolling or even at the end of rolling, or different weightings of the measured variables when determining the manipulated variable.

[0029] Wall thickness represents the difference between the outer diameter and the inner diameter of a workpiece, especially a drilled or hollow block. Additionally or alternatively, the required wall pressure or the measured wall thickness can serve as the measured variable.

[0030] Eccentricity describes the deviation of the oval from a circular shape. This measured variable may be necessary for preventive control so that the eccentricity of the workpiece can be determined before rolling and a suitable reaction can be made. For example, rolling can be controlled regardless of the eccentricity of the workpiece so that the rolling process, or in particular other manipulated or output variables, can be adjusted to achieve the desired rolling result, or so that the eccentricity can be optimized, for example, by suitable process metrology, and irregularities in the outer shape can be corrected. Eccentricity can also be a subsequent control criterion to determine if rolling has changed the eccentricity of the workpiece. Here, eccentricity can be important for both the outer diameter and the inner diameter.

[0031] The outer diameter refers to the outside diameter of the workpiece. When referring to the wall thickness, the inner diameter of the workpiece, particularly a pipe, can be determined and used as an input variable, for example.

[0032] The ovality of a workpiece represents the difference between the maximum and minimum outer diameters on one side. On the one hand, this can help determine whether process adjustments to manipulated variables are necessary to achieve the best possible rolling result. On the other hand, ovality can serve as a check for subsequent tolerance verification, among other things, or to determine how much rolling has affected the dimensions of the workpiece.

[0033] Rolling force refers to the force that a workpiece experiences during rolling or the force that the rolls exert on the workpiece during rolling. Rolling force can vary according to the dimensions and characteristics of the workpiece, but must be applied throughout the entire rolling process to ensure reliable rolling.

[0034] The mandrel holding force represents the force that the mandrel exerts on the workpiece during rolling, and corresponds to the force with which the mandrel must be held during rolling. The magnitude of the mandrel holding force can depend, among other things, on the nature of the workpiece and the workpiece feed rate. Furthermore, this force can change accordingly when adjusting the mandrel position or spread angle.

[0035] The output variable preferably comprises a manipulated variable, which is adjusted, for example, to control the rolling pass, particularly during rolling.

[0036] The manipulated variables can include, inter alia, dynamic positioning adjustment of at least one of the rolls, adjustment of the center of the rolls by adjusting all of the rolls, dynamic adjustment of the mandrel position, and / or adjustment of the spread angle. The manipulated variables are used for multivariable control, in that the manipulated variables can be used to react to input variables or the input variables can be controlled accordingly. All of the manipulated variables represent setting possibilities for the individual elements of the cross rolling unit, such as roll and mandrel settings. These setting possibilities, as determined by the manipulated variables, are used to actively influence the measured variables. For example, a particular rolling force can only be determined by the corresponding position adjustment of the top and bottom rolls, respectively.

[0037] However, additionally or alternatively, the rotational speed of the roll, or the rotational drive force acting on the roll, etc. may also be used as output variables.

[0038] In order to provide a method for adjusting the rolling passes of a cross rolling unit that allows the best possible rolling results to be achieved, the method for setting the rolling passes of a cross rolling unit with at least two rolls can be characterized in that at least one of the rolls is adjusted during rolling. It should also be understood that two or all of the rolls of the cross rolling unit can be adjusted in a correspondingly advantageous manner. This is also done in addition to or as an alternative to the previously explained basic idea that it is desirable to be able to adjust the rolling passes during rolling.

[0039] Additionally or alternatively, the method for setting the rolling passes of a cross rolling unit with at least two rolls to achieve the best possible rolling result can be characterized in that the mandrel flaring or attack angle and / or axial position are adjusted during rolling. Furthermore, by moving the mandrels, the rolling passes can be adapted during rolling to any changes or deviations in the particular rolling process, either with respect to the flaring or attack angle or the axial position of the mandrel relative to the rolls.

[0040] It should be noted that the axial position of the mandrels is typically defined relative to the rolling centerline or the pass line of the workpiece through the respective cross rolling unit, and the position of the mandrels at the rolling centerline or pass line relative to the rolls is then determined or specified, in particular by the mandrel holder, by the mandrel bar holder, or by a mandrel positioning device that holds the mandrels, and can be adjusted as needed.

[0041] Preferably, the mandrel's flaring or containment angle, which determines the angle between the mandrel and the workpiece, can be adjusted to change the shape or area of ​​the mandrel head that is in direct contact with the workpiece during drilling or rolling of the workpiece, thereby determining its position during rolling. This allows for the change of any rolling force or even the speed of the workpiece that may be required. The adjustable flaring angle can be used as needed, for example, to change or optimize the ovality, eccentricity, or generally the shape of the hole.

[0042] It is advantageous if a single roll is set against a second fixed roll with a specific rolling pass, or if a single roll is adjusted during rolling to provide a specific rolling pass. In this case, the effort to adjust the rolling pass is as small as possible, since only one roll needs to be driven or adjusted or set. Depending on the determined, measured variables and on other requirements, this may already be sufficient to achieve a good rolling result.

[0043] It is also conceivable that at least two corresponding rolls are set at a particular rolling pass or adjusted during rolling. Due to the fact that the total rolling force applied cannot be applied by one roll drive, but by at least two rolls, each roll drive applies less force when adjusting one roll. For example, when adjusting two rolls, half the force required when adjusting one roll is applied.

[0044] Advantageously, when adjusting at least two corresponding rolls, these corresponding rolls are set simultaneously with a specific rolling pass or are set simultaneously during rolling. During the simultaneous adjustment of the corresponding rolls, the rolling centerline may change position, which may be intentional. However, depending on the specific configuration of the roll positioning, this can be prevented by precisely moving the rolls relative to each other or simply by changing their tilt angle. This is very advantageous for the entire device, since the workpiece can also be moved further along its line. When changing the rolling centerline, rolling that conveys the workpiece in a straight line can no longer be guaranteed in an operationally reliable manner.

[0045] Furthermore, with preferred configurations, more accurate roll pass adjustments or roll pass settings can be provided by adjusting or setting at least two corresponding rolls rather than adjusting or setting a single roll.

[0046] To make it possible to provide an operationally reliable rolling process or one that is as fault-free as possible, the rolling force can be applied continuously by driving the roller mill positioning device, which allows the rolls to be set or adjusted even during rolling, since the risk of sticking or similar difficulties can be minimized.

[0047] Depending on the particular configuration, the roller mill can be mounted so that it can be set via multiple roll positioners or via only a single roll positioner. In the case of multiple roll positioners in a roller mill, the roll positioner can be used to achieve a specific angle change for the roll, for example, via the roll positioner. On the other hand, setting up the roller mill using only one roll positioner allows for easier setup, which can be advantageous, especially for roller mills that support both sides of the roll.

[0048] Preferably, the adjustment of the roll, rolls or mandrel is made in dependence on the determined measured variables already mentioned above, in particular not according to a rolling plan that is solely dependent on previously determined workpiece positions or times.

[0049] Generally, the rolling centerline is a theoretically and mechanically predetermined ideal line along which the rolled stock passes through the cross rolling unit. In this context, it should be emphasized that cross rolling rolls or cross rolling units are distinguished from longitudinal rolls or longitudinal rolling units by the fact that the axes of the two rolls have a parallel component to the rolling centerline of the cross rolling unit or cross rolling rolls. In the case of cross rolling units or cross rolling rolls, the roll surfaces of the rolling rolls have a rotation component perpendicular to the rolling centerline of the cross rolling unit or cross rolling rolls. This differs from longitudinal rolls in that the roll surfaces are moved parallel to the rolling centerline or parallel to the direction of mandrel movement, respectively. As a result, determining the exact roll position in a particular rolling operation is more difficult and complex than in longitudinal rolling. Furthermore, the roll position in cross rolling usually has a more complex effect on the rolling process. In particular, the corresponding roller mills and their connections to the roll housings are also very complicated.

[0050] In this context, a rolling pass particularly refers to the free space in which the cross rolling unit directs the workpiece during rolling. The rolling pass therefore particularly comprises the position of the rolls and, if present, the position of the mandrels. However, particularly with respect to the cross rolling unit, it also refers to the angular setting of the roll surfaces with respect to the workpiece relative to the rolling centerline.

[0051] It is to be understood that the features of the solutions described above or in the claims can also be combined as required to achieve advantages in corresponding additional ways.

[0052] Further advantages, objects and characteristics of the present invention will be explained by the following description of exemplary embodiments which are also illustrated in detail in the accompanying drawings. [Brief explanation of the drawings]

[0053] [Figure 1] FIG. 2 is a schematic top view of two cross rolls in a cross rolling unit. [Figure 2] FIG. 2 is a schematic side view of a first cross rolling unit. [Figure 3] FIG. 4 is a schematic side view of a second cross rolling unit. [Figure 4] FIG. 10 is a schematic front view of a third cross rolling unit. [Figure 5] FIG. 10 is a schematic side view of a third cross rolling unit. [Figure 6] FIG. 10 is a schematic front view of a fourth cross rolling unit. [Figure 7] FIG. 10 is a schematic side view of a fourth cross rolling unit. [Figure 8] FIG. 1 is a schematic side view of a workpiece passing through a cross rolling unit with a mandrel, with measured and manipulated variables. [Figure 9] FIG. 1 is a schematic diagram of a multivariable control with input and output variables. DETAILED DESCRIPTION OF THE INVENTION

[0054] The cross rolling units 10 shown in the drawings each comprise at least two rolls 20 (see Figures 1 to 3) or three rolls 20 (see Figures 4 to 7), which are supported on a roller mill 21 and in turn mounted in a roll housing 27, whereby they can be set via roll positioning devices 22.

[0055] The roll 20 is rotatable about a roll axis 25 and has a roll surface 26 in continuous contact with an elongated workpiece 32, shown in detail only in FIG.

[0056] Here, the workpiece 32 advances substantially along a rolling centerline 11. The rolling centerline 11 represents the approximate center of gravity of the passing material, or more precisely, the axis from the infeed rolling table (not shown), through the center of the rolling unit, to the outfeed rolling table (not shown).

[0057] In this case, the roll axes 25 are aligned substantially parallel to the rolling center line 11, with a slight inclination angle of 5° to 8° in the present exemplary embodiment. In deviating embodiments, other inclination angles, here possibly also with respect to the horizontal, can of course be provided.

[0058] The rolls 20 themselves have relatively complex roll surfaces 26, which in turn result in relatively complex rolling paths and in particular in various loads on the respective roller mills 21 of the rolls 20. This means that the roll axes 25 may be inclined relative to the horizontal, thereby not providing loads on the cross rolling unit 10.

[0059] 1 and 2, the roll positioning device 22 is connected to the roll housing 27 via longitudinal beams that serve as engagement points 24. Thereby, via the engagement points 24 or via the connections between the engagement points 24 and the roll housing 27, which may be referred to as engagement means 23, the rolling forces are transferred into the roll housing 27, thereby resulting in a corresponding rebound of the roll housing 27, which may ultimately result in a corresponding non-uniform loading of the roll housing 27 as a result of the non-uniform loading of the rolls 20 and the roller mill 21 already indicated above.

[0060] In the exemplary embodiment shown in Figures 4 to 7, a rigid roll housing 27 is provided. In the exemplary embodiment according to Figures 4 and 5, a sled to the roll positioning device 22 is provided. In the exemplary embodiment according to Figures 6 and 7, a hydraulic cylinder and piston device is provided, which can be used to set the roll 20 and can be defined as the engagement means 23. It should be understood that in deviating embodiments, and possibly also in the exemplary embodiment according to Figures 6 and 7, a sled can be provided in the exemplary embodiment as a roll positioning device, while in the exemplary embodiment shown in Figures 4 and 5, a hydraulic roll positioning device 22 can also be used instead of a sled.

[0061] 2 to 5, each roller mill 21 is mounted on a roll stand 27, whereby each roller mill 21 can be set by means of two roll positioning devices 22. As a result, it is possible in particular to also set the angle of the roll axis 25 relative to the rolling center line 11 or to react to non-uniform load changes.

[0062] On the other hand, the exemplary embodiment according to FIGS. 6 and 7 has only one roll positioning device 22 for the roller mill 21, which is easier in terms of design.

[0063] It should be understood that also in the exemplary embodiments according to Figures 2 to 5, only one roll positioning device 22 and / or one hydraulic roll positioning device 22 can be provided in each case, while in the exemplary embodiments according to Figures 6 and 7, it is also possible to provide two roll positioning devices 22 or a mechanical roll positioning device 22, if necessary. It is also possible to combine mechanical and hydraulic roll positioning devices 22, if necessary. Likewise, other roll positioning devices 22, such as piezoelectric or pneumatic setting means, can be provided.

[0064] As can be seen directly from the drawing, the roll surfaces 26 of the rolls 20 have a component of movement perpendicular to the rolling center line 11 of the cross rolling unit 10 during rolling. In general, therefore, it follows that the roll surfaces 26 of the rolls 20 have a component of movement perpendicular to the direction of movement of the workpieces 32 through the cross rolling unit 10 during rolling. Furthermore, the axes 25 of the two rolls 20 have a component of movement parallel to the rolling center line 11 of the cross rolling unit 10, as is very clear from the drawing.

[0065] In the exemplary embodiment shown in Fig. 2, the displacement 40 between the two roller mills of both rolls 20 is measured by placing a distance measurement system 41 between the roll reference point 50 on the roller mill 21 in each case and a datum 60 arranged on the respective roller mill 21. This measurement can easily be performed even during rolling. In particular, the same distance measurement system 41 can be used here to designate the roll reference point 50 on the first roller mill 21 as the reference datum 60 of the second roller mill 21.

[0066] It will be appreciated that in deviating embodiments, it is also possible to use only a single distance measuring system 41, which is provided only between the two roller mills 21 or between the references 50, 60, which in each case is provided on one of the two rolls 20, which may in some cases result in only a less accurate representation of the respective rolling pass.

[0067] In this exemplary embodiment, each end of the distance measurement system 41 is attached directly to the roller mill 21, so that the roller mill 21 itself serves as the roller datum point 51 or reference datum point 61. Therefore, the roller mill 21 also serves as a respective reference for measuring the displacement 40 to each other roller mill 21.

[0068] It should be understood that in the exemplary embodiment according to Fig. 2, a separate assembly can also serve as the roller datum point 51 or the reference datum point 61, as shown by way of example in the exemplary embodiment according to Fig. 3. Other assemblies can also be used as appropriate, such as assemblies provided between the roll positioning device 22 and the roller mill 21 or the longitudinal beam or housing beam, or corresponding separate assemblies can serve as supports for the roller datum point 51 or the reference datum point 61.

[0069] 3, protrusions are provided in each case as roller datum points 51 and reference datum points 61, respectively. The protrusions for roller datum points 51 are located on roller mill 21, and the protrusions for reference datum points 61 are located on a separate reference frame 62.

[0070] The reference frame 62 is decoupled from the roll housing 27 so as to provide a reference or reference datum 61 that is independent of the respective rolling forces. The latter is also the case in the exemplary embodiment according to Figures 4 and 5, where the roller datum points 51 or roller datums 50 are provided on the roller mill 21, but in deviating embodiments they may be provided on other assemblies, as is the case in the exemplary embodiment according to Figures 6 and 7, which also use the reference frame 62.

[0071] It should be understood that in deviating embodiments from the exemplary embodiment shown in Figures 3, 6 and 7, separate protrusions for providing the roller datum points 51 or reference datum frame 61 can also be omitted if this is structurally feasible, especially in terms of space. If necessary, an inclined arrangement of the rolls 20, with a resulting changed arrangement of the roller mills 21, can be used so that the distance measurement system 41 can be coupled without separate protrusions.

[0072] Furthermore, in the exemplary embodiments shown in Figures 3 to 7, distance measurements can be performed between the rolls 20 or between the roller mills 21 themselves, as illustrated by way of example in the exemplary embodiment shown in Figure 2, if desired.

[0073] In the exemplary embodiment shown in Fig. 3, the displacement 40 of only one roller mill 21 on each roll 20 is suitably measured. It should be understood that, as indicated by the dashed lines, a separate reference frame 62 can also be provided for measurements on each other roller mill 21 on each roll 20, in order to obtain a more accurate representation of the rolling path. Likewise, in the exemplary embodiments according to Figs. 4 to 7, the individual distance measuring systems 41 can be omitted if necessary, although the corresponding measurement accuracy will not be obtained.

[0074] As is very clear in the exemplary embodiment according to Figures 3 to 7, the displacement 40 between the roller mill of the roll 20 and a reference provided outside the engagement means 23 is measured. For this purpose, a reference datum 61 is arranged outside the engagement point 24 of the roll positioning device 22 of the roller mill 21. This engagement point engages with the roll housing 27.

[0075] In this embodiment, resistive, capacitive and / or inductive sensors are used for the distance measurement system 41 or distance measurement. Alternatively, optical range finders, ultrasonic sensors or radar sensors may be used as appropriate.

[0076] In this way, contact or non-contact measurements can be performed.

[0077] 8, the process of perforating a workpiece 32 by means of a mandrel 30 and two rolls 20 is shown diagrammatically. Corresponding procedures can be applied, particularly in interaction with the other cross rolling units 20 presented herein.

[0078] It should be understood that, alternatively, a hollow block with a mandrel 30 as an internal tool can also be rolled using a corresponding cross rolling unit 10. Furthermore, if desired, the internal tool or mandrel 30 can be omitted, regardless of whether a block or hollow block is being cross rolled as the workpiece 32.

[0079] 8 and 9 are exemplary manipulated and measured variables that can be advantageously used, among other manipulated and measured variables, as input and output variables, respectively, for the multivariable controller 70 in all embodiments shown herein. It should be understood that only individual measured and manipulated variables can be used if desired, and that individual measured and manipulated variables can be omitted, or other measured and manipulated variables, and variables derived therefrom, can be used for the multivariable controller 70.

[0080] For example, workpiece infeed rate 71, workpiece outfeed rate 72, wall thickness 73, eccentricity 74, outside diameter 75, ovality 76, rolling force 77, and mandrel holding force 78 may serve as measured variables, which are shown schematically in Figure 8. These measured variables, as well as other measured variables and variables derived from the measured variables, may serve as input variables for a multivariable controller 70, as shown by way of example in Figure 9.

[0081] Further illustrated schematically in Figures 8 and 9 by way of example as manipulated variables are the adjustment of the spread angle 80, the dynamic positioning adjustment 81 of the rolls 20, here used as the top and bottom rolls, the dynamic adjustment of the rolling center 82 by simultaneously adjusting the rolls used as the top and bottom rolls, and the dynamic adjustment of the mandrel position 83.

[0082] Specifically, these manipulated variables may be implemented as needed by individual output variables for the roll positioner 22 and the mandrel positioner 31, which holds the mandrel 30. Meanwhile, in this exemplary embodiment, each of these manipulated variables coordinately activates the associated actuators, i.e., the roll positioner 22 and the mandrel positioner 31, respectively, to ensure simultaneous movement of the roll 20, for example.

[0083] It should be understood that the spread angle adjustment 80 can be accomplished by corresponding adjustment of the mandrel 30, for example perpendicular to the rolling centerline 11, using the mandrel position adjustment device 31, or by dynamic adjustment 82 of the rolling center.

[0084] Alternatively, the mandrel position adjustment device 31 can adjust the axial position of the mandrel 30, i.e., the position of the mandrel 30 relative to the roll 20, as viewed along the rolling centerline 11, which can also be used as a manipulated variable if desired.

[0085] All manipulated variables shown in these exemplary embodiments can be adjusted, particularly during rolling. [Explanation of symbols]

[0086] 10 Cross rolling equipment 11 Rolling Center Line 20 rolls 21 Roller Mill 22 Roll positioning device 23 Engagement means 24 engagement points 25 Roll axis 26 Roll surface 27 Roll housing 30 mandrels 31 Mandrel position adjustment device 32 workpieces 40 Displacement (shown as an example) 41 Distance measurement system 50 rolls of datum (given as an example) 51 Datum points of the roll (given as an example) 60 Reference datum (specified as an example) 61 Reference datum points (specified as examples) 62 Reference Frame 70 Multivariable Control 71 Workpiece feed rate 72 Workpiece feed rate 73 wall thickness 74 Eccentricity 75 outer diameter 76 Ellipticity 77 Rolling force 78 Mandrel retention force 80 Adjusting the spread angle 81 Individual Dynamic Positioning Adjustment 82 Dynamic adjustment of rolling center 83 Dynamic adjustment of mandrel position

Claims

1. 1. A cross rolling unit (10) having at least two rolls (20) and a roll housing (27) in which at least one of the rolls (20) is mounted, whereby the position of the roll (20) can be adjusted to vary the rolling pass, a portion where a roll positioning device (22) is connected to the housing; a part connected to a chock (21) that can be moved relative to the part connected to the housing during rolling; a cross rolling unit (10) characterized in that both of them can be adjusted relative to each other, and (i) the roll positioning devices (22) are dimensioned to be able to apply a rolling force, and / or (ii) the mandrel position of the mandrel (30) can be adjusted horizontally relative to the workpiece during rolling by a mandrel position adjusting device (31), and a multivariable control (70) with input variables including at least two measured variables and at least one output variable can be performed during the entire rolling process.

2. 2. The cross rolling unit (10) according to claim 1, characterized in that the roll positioning device (22) comprises at least one hydraulic cylinder that can be moved faster than 30 mm / s and / or can operate at more than 50,000 hPa, its stroke height being less than 150 mm and that can be activated by a high-speed valve.

3. 3. A cross rolling unit (10) according to claim 1 or 2, characterized in that two roll positioning devices (22) are provided on at least one of the rolls (20).

4. 4. The cross rolling unit (10) according to claim 1, wherein the input variables and the output variables are both determinable by and / or transmitted to the roll positioning device (22), and / or the input variables comprise measured variables such as workpiece infeed rate (71), workpiece outfeed rate (72), wall thickness (73), eccentricity (74), outer diameter (75), ovality (76), rolling force (77), and / or mandrel holding force (78), and / or the output variables comprise manipulated variables such as dynamic position adjustment (81) of at least one of the rolls (20), adjustment of the rolling center by adjusting all rolls (20), dynamic adjustment of the mandrel position (83), and / or adjustment of the divergence angle (80).

5. 1. A method for setting a rolling pass of a cross rolling unit (10) having at least two rolls (20), characterized in that at least one of the rolls (20) and / or the expansion angle (80) and / or the axial position of the mandrel (30) are adjusted during the entire rolling process by a multivariable control (70) having input variables including at least two measured variables and at least one output variable.

6. 6. A method for setting a rolling pass according to claim 5, characterized in that the single roll (20) is set to have a predetermined rolling pass relative to the second fixed roll (20) and / or is adjusted during rolling.

7. 7. Method for setting a rolling pass according to claim 5 or 6, characterized in that at least two corresponding rolls (20) are set with a predetermined rolling pass.

8. Method for setting a rolling pass according to any one of claims 5 to 7, characterized in that at least two corresponding rolls (20) are adjusted during rolling.

9. 9. A method for setting a rolling pass according to claim 8, characterized in that at least two corresponding rolls (20) are set simultaneously with a predetermined rolling pass and / or adjusted simultaneously during rolling.

10. Method for setting a rolling pass according to any one of claims 5 to 9, characterized in that the rolling force is applied continuously by driving the roll positioning device (22).

11. 10. Method for setting a rolling pass according to any one of claims 5 to 9, characterized in that adjustments of the rolls (20) and / or the mandrels (30) are performed in dependence on established measured variables.

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