Roll stand

Abstract

A roll stand (1) includes a roll (3), in particular a backup roll, mounted via oil film bearings (2). Each oil film bearing (2) has a sealing system for sealing the oil film bearing (2) to prevent oil leakage and a coolant ingress. The oil film bearing (2) is integrated into an oil-circulating lubrication system (4), which is fluidically connected to the oil film bearing (2) via oil feed lines (5) and an oil discharge line (6). A first sensor (11) is arranged in the oil feed line (5) and a second sensor (12) is arranged in the oil discharge line (6). The two sensors (11, 12) are designed to determine the coolant content in the relevant oil volume flow.

Claims

1-10. (canceled)

11. A roll stand (1), comprising: a roll (3); an oil film bearing (2) by which the roll (3) is mounted, the oil film bearing (2) comprising a sealing system for sealing the oil film bearing (2) to prevent oil leakage and coolant ingress; an oil-circulating lubrication system (4) fluidically connected to the oil film bearing (2) via an oil feed line (5) and an oil discharge line (6); a first sensor (11) arranged in the oil feed line (5) and designed to determine a coolant content in an oil volume flow in the oil feed line (5); and a second sensor (12) arranged in the oil discharge line (6) and designed to determine a coolant content in an oil volume flow in the oil discharge line (6).

12. The roll stand (1) according to claim 11, wherein the roll (3) is a backup roll.

13. The roll stand (1) according to claim 11, wherein the first sensor (11) and/or the second sensor (12) is a viscosity sensor, a conductivity sensor, an optical sensor, and/or a density sensor.

14. The roll stand (1) according to claim 11, wherein the oil-circulating lubrication system (4) comprises a storage tank (7) with a fill level sensor (9).

15. The roll stand (1) according to claim 11, further comprising a distance sensor (14), by which an axial distance between a reference surface on a roll body side (27) of a chock (20) and an end surface (29) of a roll body arranged axially opposite the chock (20) can be determined.

16. The roll stand (1) according to claim 11, further comprising a distance sensor (14), by which an axial distance between an annular channel (28) connected to a chock (20) and a deflector ring (30) connected to a roll body arranged axially opposite the chock (20) can be determined.

17. The roll stand (1) according to claim 11, further comprising a third sensor (15) arranged within the sealing system.

18. The roll stand (1) according to claim 11, further comprising a third sensor (15) arranged in the oil film bearing (2) between an oil-side seal and a coolant-side seal.

19. The roll stand (1) according to claim 11, further comprising a fill level sensor (16) arranged inside the oil film bearing (2), by which a fill level of oil in an oil sump can be determined.

20. The roll stand (1) according to claim 11, wherein the oil film bearing (2) comprises a measuring device by which a condition of at least one element selected from the group consisting of a journal bushing (18), a pressure shoulder ring (22), a thrust bearing unit (23), and a thrust bearing housing (24) can be determined inside the oil film bearing (2).

21. The roll stand (1) according to claim 11, further comprising a measuring device arranged in a coupling region (13) of the oil feed line (5) and/or the oil discharge line (6), by which a coupling connection can be detected.

22. A method for detecting contamination of an oil caused by a coolant in an oil film bearing (2) of a roll stand (1), wherein the oil film bearing (2) comprises a sealing system for sealing the oil film bearing (2) to prevent oil leakage and coolant ingress and wherein an oil-circulating lubrication system (4) fluidically connects the oil film bearing (2) via an oil feed line (5) and an oil discharge line (6), the method comprising: determining, by a first sensor (11) arranged in the oil feed line (5), a coolant content in an oil volume flow in the oil feed line (5); and determining, by a second sensor (12) arranged in the oil discharge line (6), a coolant content in an oil volume flow in the oil discharge line (6).

23. A method for detecting losses of an oil in an oil film bearing (2) of a roll stand (1), wherein the oil film bearing (2) comprises a sealing system for sealing the oil film bearing (2) to prevent oil leakage and coolant ingress and wherein the oil film bearing (2) is integrated into an oil-circulating lubrication system (4), which comprises a storage tank (7) with a fill level sensor (9) and which is fluidically connected to the oil film bearing (2) via an oil feed line (5) and an oil discharge line (6), the method comprising: determining, by a first sensor (11) arranged in the oil feed line (5), a coolant content in an oil volume flow in the oil feed line (5); and determining, by a second sensor (12) arranged in the oil discharge line (6), a coolant content in an oil volume flow in the oil discharge line (6).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0021] FIG. 1 shows an embodiment of the roll stand.

[0022] FIG. 2 shows a sectional view of an oil film bearing with a backup roll.

[0023] FIG. 3 shows an enlarged illustration of the region A marked in FIG. 2.

DETAILED DESCRIPTION

[0024] FIG. 1 shows an embodiment of the roll stand 1, which has a backup roll 3 supported by oil film bearings 2. Both oil film bearings 2 each have a sealing system for sealing the oil film bearing 2 to prevent oil leakage and a coolant ingress and are integrated into an oil-circulating lubrication system 4. The oil-circulating lubrication system 4 is fluidically connected to the two oil film bearings 2 via oil feed lines 5 and an oil discharge line 6 and also has a storage tank 7, a pump 8 and other units not shown here, such as a filter, an oil cooler and a control station. Thus, the oil can be fed to the relevant oil film bearing 2 by means of the pump 8 via the relevant feed lines 5 and discharged again via discharge lines 6. In order to be able to determine the fill level of the oil in the storage tank 7, the latter comprises a fill level sensor 9, which is connected by means of signals to an evaluation device 10 and continuously transmits the fill levels to the latter.

[0025] The roll stand 1 has a first sensor 11 arranged in the oil feed line 5 and a second sensor 12 arranged in the oil discharge line 6, by means of which the coolant content in the relevant oil volume flow can be determined. As shown in FIG. 1, both sensors 11, 12 are also connected to the evaluation unit 10 by means of signals, such that the information determined can be transmitted to it and evaluated by it. Both sensors 11, 12 are designed in the form of a viscosity sensor. Alternatively, the two sensors 11, 12 may be in the form of conductivity sensors, in the form of optical sensors or in the form of density sensors.

[0026] Furthermore, the oil feed line 5 and the oil discharge line 6 in the embodiment shown here comprise a measuring device 14 arranged in the coupling region 13, by means of which the coupling connections can be detected. The measuring devices 14, which are designed as electrical contactors, are also connected to the evaluation device 10 by means of signals.

[0027] As already explained, by continuously detecting and comparing coolant contents in the oil downstream and upstream of the oil film bearing 2, oil contamination by the coolant, such as water ingress, can be directly detected and, if necessary, localized. By continuously monitoring and evaluating the fill level of the storage tank 7 and taking into account the previously determined oil contamination, losses of oil can also be reliably determined. To localize the source of interference, the roll stand 1 shown in FIG. 1 comprises further sensors 14, 15, 16, whose position is indicated in FIG. 1 and whose function is explained in more detail in FIGS. 2 and 3 below. As shown in FIG. 1, such sensors 14, 15, 15 are also connected to the evaluation device 10 by means of signals.

[0028] FIG. 2 shows a sectional view of one of the two oil film bearings 2, in which the backup roll 3 is mounted via its conically formed roll journal 17. In the embodiment shown here, the oil film bearing 2 comprises a conically formed journal bushing 18, which is rotatably mounted in a bearing bushing 19, wherein the bearing bushing 19 in turn is enclosed by a chock 20. A lubricating film 21 is typically formed in the load zone between the stationary bearing bushing 19 and the journal bushing 18, which rotates together with the roll journal 17 during rolling operation.

[0029] In the embodiment presently shown, the oil film bearing 2 is further connected to a thrust bearing unit 23 via a pressure shoulder ring 22, which comprises a thrust bearing housing 24 and a thrust bearing 25.

[0030] As also shown in FIG. 2, the roll stand 1 has a further fill level sensor 16 arranged inside the oil film bearing 2, by means of which the fill level 26 of the oil in the lubricant sump can be determined.

[0031] FIG. 3 shows the region A marked in FIG. 2 in an enlarged view.

[0032] What can be seen in this illustration is, on the one hand, the distance sensor 14, which is firmly connected to the chock 20 and by means of which the axial distance between a reference surface 27 of the chock 20 on the roll body side, in particular of an annular channel 28 connected to the chock 20, and the end surface 29 of the roll body of the backup roll 3, in particular of a deflector ring 30 connected to the roll body, arranged axially opposite the chock 20, can be determined. The oil film bearing 2 is sealed off from the coolant at this point by a sealing lip 31 arranged between the annular channel 28 and the deflector ring 30. The position of the sealing lip 31 relative to the associated counter surface can then be continuously monitored by measuring the axial distance.

[0033] In the present embodiment, the oil film bearing 2 further comprises a high-performance journal seal 32 arranged between an inner annular surface 33 of the annular channel 28 and the roll journal 17 and seals the oil film bearing 2 from a coolant ingress and an oil outlet. In order to detect any exchange of media between the oil side and the coolant side, the oil film bearing 2 has the third sensor 15, which is advantageously arranged between the sealing lip on the oil side and the coolant side at the lowest point of the sealing system, preferably in a so-called 6 o'clock position. The third sensor 15 can be in the form of a viscosity sensor, an optical sensor, a conductivity sensor and/or a density sensor.

LIST OF REFERENCE SIGNS

[0034] 1 Roll stand [0035] 2 Oil film bearing [0036] 3 Backup roll [0037] 4 Oil-circulating lubrication system [0038] 5 Feed line [0039] 6 Discharge line [0040] 7 Storage tank [0041] 8 Pump [0042] 9 Fill level sensor [0043] 10 Evaluation device [0044] 11 First sensor [0045] 12 Second sensor [0046] 13 Coupling region [0047] 14 Distance sensor [0048] 15 Third sensor [0049] 16 (Second) fill level sensor [0050] 17 Roll journal [0051] 18 Journal bushing [0052] 19 Bearing bush [0053] 20 Chock [0054] 21 Lubricating film [0055] 22 Pressure shoulder ring [0056] 23 Thrust bearing unit [0057] 24 Thrust bearing housing [0058] 25 Thrust bearing [0059] 26 Fill level of the oil [0060] 27 Reference surface [0061] 28 Annular channel [0062] 29 End surface [0063] 30 Deflector ring [0064] 31 Sealing lip [0065] 32 High-performance journal seal [0066] 33 Inner annular surface