CONSTRUCTIVE DESIGN AND ARRANGEMENT OF A DISSIPATOR FOR SUPPRESSING VIBRATIONS IN A ROLL STAND

Abstract

A dissipator includes a hydraulic inductor, a hydraulic resistor and a hydraulic capacitor for damping vibrations in a roll stand for producing flat metal rolled material. The dissipator has an intermediate piece with a first hydraulic interface for directly hydraulically-mechanically linking to an adjusting cylinder of the roll stand. Via a second hydraulic interface, a valve block with a control valve for the adjusting cylinder can be directly hydraulically-mechanically linked to the dissipator. The intermediate piece can be formed as a rigid block, to which the hydraulic resistor and the hydraulic capacitor are detachably fluidically connected. The hydraulic inductor is introduced into the block, preferably in the form of a tubular cavity and fluidically connected to the first and second hydraulic interfaces.

Claims

1-9. (canceled)

10. A dissipator for damping vibrations in a roll stand for producing flat metallic rolled material, comprising: a hydraulic inductor; a hydraulic resistor; and a hydraulic capacitor; wherein the dissipator has a frequency-dependent damping effect that is tuned to a characteristic vibration frequency of the roll stand; wherein the dissipator has an intermediate piece configured to be fluidically arranged between an adjusting cylinder of the roll stand and a valve block having a control valve assigned to the adjusting cylinder; wherein the intermediate piece has a first hydraulic interface for direct hydraulic-mechanical linking of the dissipator to the adjusting cylinder; and wherein the intermediate piece has a second hydraulic interface for hydraulic linking of the valve block to the dissipator.

11. The dissipator as claimed in claim 10, wherein the second hydraulic interface provides direct hydraulic-mechanical linking of the valve block to the dissipator.

12. The dissipator as claimed in claim 10, wherein the hydraulic resistor comprises an adjustable valve.

13. The dissipator as claimed in claim 10, wherein: the dissipator has a design frequency in a range of 70 Hz to 130 Hz; the hydraulic resistor comprises a valve having a maximum flow rate of 300 liters per minute and a maximum differential pressure of 5 bar; the hydraulic inductor comprises a tubular cavity with a length of 600 mm to 800 mm and a largest diameter of 50 mm to 65 mm; and the hydraulic capacitor comprises a pressure vessel having a maximum pressure of 300 bar with a hydraulic volume of 10 to 20 liters.

14. The dissipator as claimed in claim 13, wherein the hydraulic capacitor further comprises: a further pressure vessel directly hydraulically-mechanically linked to the hydraulic capacitor; and a clampable adjusting device configured to set a further hydraulic volume of the further pressure vessel to a value between 0% and 30% of the hydraulic volume of the pressure vessel.

15. The dissipator as claimed in claim 10, wherein: the intermediate piece comprises a rigid block, the hydraulic resistor and the hydraulic capacitor being detachably fluidically connected to the rigid block; the hydraulic inductor is fluidically connected to the hydraulic resistor or to the hydraulic capacitor so that the hydraulic inductor, the hydraulic resistor, and the hydraulic capacitor are fluidically coupled to one another in series; and the hydraulic inductor is made in the intermediate piece as a tubular cavity and is fluidically connected to the first and second hydraulic interfaces.

16. The dissipator as claimed in claim 15, wherein the hydraulic resistor is a cartridge valve configured to deflect a conducted flow of hydraulic liquid at a right angle and to connect the hydraulic inductor fluidically to the hydraulic capacitor.

17. The dissipator as claimed in claim 16, wherein the cartridge valve comprises an infinitely variable proportional valve with a controllable opening position between 0 and 100% of a maximum opening position and is configured to report the set opening position.

18. The dissipator as claimed in claim 15, wherein the dissipator comprises a cover cap mechanically detachable from the intermediate piece, the cover cap configured to delimit the hydraulic inductor at one end.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0047] The above-described properties, features and advantages of the invention and the manner in which these are achieved become clearer and more easily understandable in connection with the following description of the exemplary embodiments of the invention, which are explained in more detail in connection with the figures. In the figures,

[0048] FIG. 1 shows a hydraulic line schema of a valve block according to the prior art, which is arranged directly on an adjusting cylinder of a roll stand;

[0049] FIG. 2 shows a hydraulic line schema of a first exemplary embodiment of the dissipator according to the invention, which is arranged directly on an adjusting cylinder of a roll stand;

[0050] FIGS. 3-5 show three views of the schematic structure and the schematic arrangement of the dissipator according to the invention from FIG. 2;

[0051] FIG. 6 shows a section along the X-Z plane through the intermediate piece of the first exemplary embodiment of the dissipator according to the invention;

[0052] FIG. 7 shows a schematic structure of an adjustable hydraulic capacitor of the dissipator according to the invention in a second exemplary embodiment.

DETAILED DESCRIPTION

[0053] FIG. 1 shows an adjusting cylinder 2, to which, according to the prior art, a valve block 6 having a control valve 11 and a pressure valve 12 within the above-defined meaning is directly hydraulically-mechanically linked. The adjusting cylinder 2 has a cylinder housing 3 and a piston 4 and acts along a first longitudinal axis 5 of the piston 4, for example on a supporting roll of a roll stand (not shown in FIG. 1). The adjusting cylinder 2 in FIG. 1 is designed by way of example as a single-action cylinder, the piston-side pressure chamber 7 of which is connected via a first fluid line 13 to the control valve 11, and the ring-side pressure chamber 8 of which is connected via a second fluid line 14 to the pressure valve 12. The first and the second fluid line 13, 14 are each fluidic passages through the cylinder housing 3. In addition, the piston 4 of the adjusting cylinder 2 is sealed off from the cylinder housing 3 with the aid of sealing elements 17, and the piston-side pressure chamber 7 is sealed off from the ring-side pressure chamber 8 with the aid of sealing elements 18 that enclose the piston 4 circumferentially.

[0054] The control valve 11 and the pressure valve 12 are connected to further hydraulic lines (not shown in FIG. 1) via a valve block 6. In order to allow a compact design of the valve block 6, the second fluid line 14 comprises a portion guided along the first longitudinal axis 5 inside the cylinder housing 3, wherein the portion opens into a corresponding fluidic interface for the pressure valve 12 on the outside of the cylinder housing 3. Alternatively, it is also possible to connect the pressure valve 12 fluidically via a directly guided port 9 on the outside of the cylinder housing 3 at the height of the ring-side pressure chamber 8 (not shown in FIG. 1). Vibrations in a roll stand in which the adjusting cylinder 2 is installed are primarily transmitted via the piston 4 of the adjusting cylinder 2 into the piston-side pressure chamber 7 and cause corresponding pressure fluctuations 16 therein, which are transmitted undamped via the first fluid line 13 to the control valve 11.

[0055] FIG. 2 shows an adjusting cylinder 2, which is designed by way of example as a cylinder that acts on both sides, in which a control valve 11 controls a flow of hydraulic liquid into and out of both a piston-side pressure chamber 7 and a ring-side pressure chamber 8.

[0056] The control valve 11 is arranged in a valve block 6, which is directly hydraulically-mechanically linked to an intermediate piece 20 of a dissipator 1 according to the invention. For this purpose, the intermediate piece 20 has, on the valve block side, in each case two fluidic passage openings 33, 34 corresponding to the piston-side and ring-side pressure chambers 7, 8 and is mechanically connected to the intermediate piece 20 via connection means 29 (not shown in FIG. 2). The intermediate piece 20 itself is in turn directly hydraulically-mechanically linked to the cylinder housing 3 of the adjusting cylinder 2. For this purpose, the intermediate piece 20 comprises, on the cylinder side, in each case one fluidic passage opening 31, 32 for the first and second fluid lines 13, 14 and is again connected mechanically to the cylinder housing 3 via connection means 30 (not shown in FIG. 2). The cylinder-side fluidic passage openings 31, 32 are part of the first hydraulic interface 24 of the intermediate piece 20; the valve-block-side fluidic passage openings 33, 34 likewise form elements of its second hydraulic interface 26.

[0057] The fluidic passage openings 32 and 34 corresponding to the ring-side pressure chamber 8 are connected to one another only fluidically via a simple bore 36 inside the intermediate piece. In contrast, the fluidic passage openings 31 and 33 corresponding to the piston-side pressure chamber 7 are both fluidically connected to one another and fluidically linked to the hydraulic components of the dissipator 1 inside the intermediate piece. This is shown symbolically in FIG. 2 by a line branching off to a hydraulic capacitor 23 of the dissipator 1. In other words: while the intermediate piece 20 only forms a simple fluidic connection between the ring-side pressure chamber 8 of the adjusting cylinder 2 and the control valve 11, the piston-side pressure chamber 7 and the control valve 11 are both fluidically connected to one another and additionally linked to the hydraulic components of the dissipator 1 by means of the intermediate piece 20.

[0058] Pressure fluctuations 16 caused by the roll stand in the piston-side pressure chamber 7 are largely damped away by the dissipator 1, so that the control valve 11 and hydraulic lines connected thereto or further hydraulic units are subject at most to greatly attenuated pressure fluctuations 16.

[0059] FIG. 3, FIG. 4 and FIG. 5 each show a section along the Y-Z, X-Y and X-Z planes, respectively, through a schematic structure of the dissipator 1 according to the invention in a first exemplary embodiment, wherein the dissipator 1 is arranged on an adjusting cylinder 2 of a roll stand, as in FIG. 2. The size ratios of the individual components shown in FIG. 3-5 are not true to scale and only serve to illustrate their arrangement. The relative orientation of the shown combination of adjusting cylinder 2, dissipator 1 and valve block 6 in relation to the likewise shown orthogonal coordinate system of X, Y and Z axes is the same in each of FIG. 3-5.

[0060] The dissipator 1 shown in FIG. 3-5 comprises an intermediate piece 20 designed as a rigid block, in which the hydraulic inductor 21 is made in the form of a cylindrical bore along a second longitudinal axis 27. The cylindrical bore is fluidically connected via a fluidic passage opening 33 to a control valve 11 (not shown in FIG. 3-5) installed in the valve block 6 and via a further fluidic passage opening 31 to a first fluid line 13 of the adjusting cylinder 2. Furthermore, the hydraulic inductor 21 is delimited at the end closer to the fluidic passage openings 31 and 33 by means of a mechanically detachable cover cap 28 and is fluidically connected at the opposite end to a hydraulic resistor 22.

[0061] The hydraulic resistor 22 is implemented as a cartridge valve 22, which is designed to deflect a conducted flow of hydraulic liquid at a right angle to the second longitudinal axis 27. Furthermore, the hydraulic resistor 22 is fluidically connected to a hydraulic capacitor 23, which is designed as a cylindrical fluid chamber for receiving hydraulic liquid and is fastened to the intermediate piece 20 in the direction of its cylinder axis perpendicularly to the second longitudinal axis 27. The hydraulic capacitor 23 has a predefined volume of 10-20 liters and is filled with hydraulic liquid during the operation of the dissipator 1. The hydraulic resistor 22 and the hydraulic capacitor 23 are each detachably connected fluidically to the intermediate piece 20. In the arrangement shown in FIG. 3-5, the hydraulic inductor 21, the hydraulic resistor 22 and the hydraulic capacitor 23 are fluidically coupled to one another in series.

[0062] In the intermediate piece 20 of the exemplary embodiment shown, a bore 36 is also made, which fluidically connects the second fluid line 14 of the adjusting cylinder 2 via fluidic passage openings 32 and 34 to the control valve 11 and pressure valve 12 (not shown in FIG. 3-5), respectively, installed in the valve block 6. Furthermore, fit bores 29 for connection means 30 such as screws (only shown in FIG. 3 for reasons of clarity), by means of which the intermediate piece 20 can be mechanically fastened to the cylinder housing 3, are made in the intermediate piece 20.

[0063] FIG. 6 shows a section through the intermediate piece 20 normally to the hydraulic inductor 21 running in the direction of the second longitudinal axis 27: this is linked to the fluidic passage openings 31 and 33 via an obliquely running bore 39 made in the intermediate piece. The cylindrical bore forming the hydraulic inductor 21 along the second longitudinal axis 27 and the bore 36 running in a plane normal thereto are made as intersecting bores in the intermediate piece 20, wherein the bore 36 has a cross-sectional area, normal to its bore axis, that is 25% to 100% of the cross-sectional area of the hydraulic inductor 21. The bore 36 connecting the fluidic passage openings 32 and 34 is made obliquely in the intermediate piece 20, parallel to the bore 39.

[0064] Fit bores 29 are made in the intermediate piece 20 for receiving screws 30, with the aid of which the intermediate piece 20 can be fastened to the cylinder housing 3 of the adjusting cylinder 2 (not shown in FIG. 6). In addition, the intermediate piece 20 has threaded bores 25, corresponding to the fit bores 29, for further screws 30 for fastening the valve block 6 (not shown in FIG. 6) to the intermediate piece 20. Furthermore, a retaining device 35 in the form of an eyelet is attached to the intermediate piece 20, so that the dissipator 1 in the assembled state can be positioned on an adjusting cylinder 2 of a roll stand by means of a hoist device and connected to the adjusting cylinder and to a valve block 6.

[0065] At the fluidic passage openings 31 and 32, recesses 38 for annular sealing means 37 are also made in the intermediate piece 20 in order to prevent the escape of hydraulic liquid conducted through the intermediate piece 20 on passing into the first and second fluid lines 13 and 14 of the adjusting cylinder 2. For the same purpose, annular sealing means 37 can be arranged at the fluidic passage openings 33 and 34 between the intermediate piece 20 and the valve block 6 (not shown in FIG. 6). The fluidic passage openings 31 and 32 form, together with the recesses 38 and the sealing means 37 and with the fit bores 29, the first hydraulic interface 24 of the dissipator 1. Likewise, the fluidic passage openings 33 and 34 form, together with the corresponding sealing means 37 and the threaded bores 25, its second hydraulic interface 26.

[0066] The threaded bores 25 have an offset 40 along the Z axis relative to the fit bores 29. Likewise, the valve-block-side fluidic passage openings 33 and 34 have the same offset 40 along the Z axis relative to the corresponding cylinder-side passage openings 31 and 32. This offset arrangement of screws 30 relative to further screws 30 and of fluidic passage openings 31 and 32 relative to corresponding fluidic passage openings 33 and 34 means that the dissipator 1 according to the invention can be installed subsequently between an adjusting cylinder 2 and a valve block 6 connected hydraulically thereto, without changes having to be made to the hydraulic interfaces of the adjusting cylinder 2 or of the valve block 6.

[0067] FIG. 7 shows a section through a dissipator 1 according to the invention in a second exemplary embodiment, in which the hydraulic capacitor 23 is adjustable and is fluidically coupled in series to a hydraulic inductor 21 via a hydraulic resistor 22. The hydraulic resistor 22 is in turn designed as a cartridge valve 22 with an adjustable opening position 55, which is reported via corresponding electrical signal lines (not shown in FIG. 7) of the control electronics of the cartridge valve 22. In this case, the hydraulic capacitor 23 comprises a cylindrical fluid chamber 43 for receiving hydraulic liquid and has a further pressure vessel 41, which is directly hydraulically-mechanically linked to the cylindrical fluid chamber 43 via a third hydraulic interface 42 with a further fluidic passage opening 44. To largely avoid undesired reflections of pressure waves at the fluidic passage opening 44, its cross-sectional area is 25% to 100% of the axial cross-sectional area of the cylindrical fluid chamber 43.

[0068] Furthermore, the hydraulic capacitor 23 has a clampable adjusting device 45, which comprises: a piston 46, which is mounted displaceably inside the further pressure vessel 41 and has a piston rod 47; a hydraulic clamping device 48 for clamping the piston rod 47; a hydraulic adjustment valve 49 for moving the piston 46; and a hydraulic pressure valve 50 for opening the clamping device 48.

[0069] The clamping device 48 can be operated in a so-called non-energized state, in which the piston rod 47 is held in a position by the clamping device 48 and in which the clamping device 48 is not loaded with any hydraulic pressure or supplied with any electrical energy. The clamping force for the piston rod 47 is applied by energy-saving mechanical holding elements: in the exemplary embodiment shown in FIG. 7, these are designed as a compressible conical seat 51, which is pressed by a compression spring 53 against the piston rod 47 by means of a complementary press fit 52 and thereby fixes the piston rod.

[0070] By activation of the pressure valve 50, a hydraulic pressure chamber 54 opposite the compression spring 53 is loaded with pressurized hydraulic liquid, and the press fit 52 is displaced against the compression spring 53, so that the clamping of the conical seat 51 is undone. In addition, mechanical energy is absorbed by the compression spring 53 as a result of the displacement of the press fit 52. Via the hydraulic adjustment valve 49, the piston 46 can then be moved into a desired position, wherein the hydraulic volume in the further pressure vessel 41 between the fluidic passage opening 44 and the piston 46 can be set to a value between 0% and 30% of the hydraulic volume of the cylindrical fluid chamber 43. As soon as the piston 46 has reached the desired position, the pressure in the hydraulic pressure chamber 54 can be reduced to a value below a lower threshold value by deactivating the pressure valve 50, so that the force of the compression spring 53 predominates and this presses the press fit 52 against the conical seat 51 owing to the previously absorbed mechanical energy, so that the conical seat locks the piston rod 47 again.

List of Reference Signs

[0071] 1 Dissipator [0072] 2 Adjusting cylinder [0073] 3 Cylinder housing [0074] 4 Piston [0075] 5 First longitudinal axis [0076] 6 Valve block [0077] 7 Piston-side pressure chamber [0078] 8 Ring-side pressure chamber [0079] 9 Directly guided port [0080] 11 Control valve [0081] 12 Pressure valve [0082] 13 First fluid line [0083] 14 Second fluid line [0084] 16, 16 Pressure fluctuations [0085] 17 Sealing elements [0086] 20 Intermediate piece [0087] 21 Hydraulic inductor [0088] 22 Hydraulic resistor [0089] 22 Cartridge valve [0090] 23 Hydraulic capacitor [0091] 24 First hydraulic interface [0092] 25 Threaded bore [0093] 26 Second hydraulic interface [0094] 27 Second longitudinal axis [0095] 28 Cover cap [0096] 29 Fit bore [0097] 30, 30 Connection means, screw [0098] 31 . . . 34 Fluidic passage opening [0099] 35 Retaining device [0100] 36 Bore [0101] 37 Sealing means [0102] 38 Recess [0103] 39 Bore [0104] 40 Offset [0105] 41 Further pressure vessel [0106] 42 Third hydraulic interface [0107] 43 Cylindrical fluid chamber [0108] 44 Fluidic passage opening [0109] 45 Clampable adjusting device [0110] 46 Piston [0111] 47 Piston rod [0112] 48 Clamping device [0113] 49 Adjustment valve [0114] 50 Pressure valve [0115] 51 Conical seat [0116] 52 Press fit [0117] 53 Compression spring [0118] 54 Hydraulic pressure chamber [0119] 55 Opening position