ROLLING STAND FOR THE ROLLING OF ROLLING STOCK

Abstract

The invention relates to a rolling stand and a rolling mill for the rolling of preferably metallic rolling stock. Known rolling stands of this type typically have two back-up rolls (110) which are rotatably mounted by way of their roll journals in chocks which function as oil film bearings. The oil film bearings are supplied with coolant and/or lubricant by means of a low-pressure circuit which has at least one low-pressure pump (130) for conveying the coolant and/or lubricant. To reduce the costs for driving the low-pressure pump (130), there is provided according to the invention a gear mechanism which is arranged on the roll face-remote side of at least one of the chocks in order to rotationally couple the at least one low-pressure pump (130) to the back-up roll journal (120) which is rotatably mounted in the chock.

Claims

1. A rolling stand (100) for rolling preferably metallic rolling stock comprising two back-up rolls each with two back-up roll journals (110), four chocks (120) in the form of oil film bearings, each with a cylindrical receiving space for the rotatable support of one of the back-up roll journals (110), wherein the chocks comprise in their interior at least one low-pressure supply conduit (122) for supplying coolant and/or lubricant into the receiving space and comprise at least one low-pressure discharge conduit (124) for removing the coolant and/or lubricant out of the receiving space, and at least one low-pressure circuit with a low-pressure supply lines (122) for connecting a tank (140) for the coolant and/or lubricant to the low-pressure supply conduit (122) of the chock, with low-pressure discharge lines (124) for connecting the low-pressure discharge conduit to the tank, and with at least one low-pressure pump (130) for delivering the coolant and/or lubricant into the low-pressure circuit, characterized in that a gear mechanism (150) is provided which is arranged on the roll face-remote side of at least one of the chocks for the rotational coupling of the at least one low-pressure pump (130) to the back-up roll journal (110) rotatably supported in the receiving space.

2. The rolling stand (100) according to claim 1, characterized in that the gear mechanism (150) is constructed as a gear mechanism with a pinion (152) and a drive gear (154) which are directly or indirectly coupled to one another in a rotational manner, and that the pinion (152) is placed in a non-rotating manner on the drive shaft (134) of the low-pressure pump (130) or that the free end of the drive shaft is constructed as the pinion (152).

3. The rolling stand (100) according to claim 2, characterized in that the drive gear (154) is designed as a gear ring (154) with toothing on the outside and which is preferably connected on the roll face-remote side in a non-rotating manner to the back-up roll journal (110) or to a journal bush (114) set in a non-rotating manner on the back-up roll journal, and that the low-pressure pump (130) is arranged in such a manner that that the pinion (152) of its drive shaft (134) engages preferably directly with the gear ring (154) with toothing on the outside.

4. The rolling stand (100) according to claim 2, characterized in that the drive gear (154) is designed as a gear ring (154) with toothing on the inside and which is preferably connected on the roll face-remote side in a non-rotating manner to the back-up roll journal (110) wherein the low-pressure pump (130) is arranged in such a manner in front that that the pinion (152) of its drive shaft (134) engages preferably directly with the gear ring (154) with toothing on the inside.

5. The rolling stand (100) according to claim 1, characterized in that the low-pressure pump (130) is integrated into the chock (120), for example, is built into a recess of the chock.

6. The rolling stand (100) according to claim 1, characterized in that the at least one chock (120) comprises a bearing bush (128) arranged in a non-rotating manner which sets the receiving space, wherein an at least one low-pressure supply conduit and one low-pressure discharge conduit (122, 124) for the coolant and/or lubricant in the chock penetrate the bearing bush.

7. The rolling stand (100) according to claim 1, characterized in that two work rolls (180) are provided which are arranged between the two back-up rolls and which set a roll slot for rolling the rolling stock.

8. The rolling stand (100) according to claim 1, characterized in that the at least one low-pressure pump (130) is built into the low-pressure supply lines (122) and/or into the low-pressure discharge lines (124) of the low-pressure circuit.

9. The rolling stand (100) according to claim 1, characterized in that the oil film bearing is designed to be operated quasi without loss of oil and that at least two tanks (140, 140) with at least two associated low-pressure circuits for the four oil film bearings are individually associated with the rolling stand (100).

10. The rolling stand (100) according to claim 9, characterized in that a first common low-pressure circuit with a first low-pressure pump (130) and a first common tank (140) for the two oil film bearings of the upper and of the lower back-up roll is provided on the roll frame on the drive side (100), and that a second common low-pressure circuit with a second low-pressure pump (130) and a second common tank (140) for the oil film bearing of the upper and of the lower back-up roll is provided on the roll frame on the operating side (100).

11. The rolling stand (100) according to claim 10, characterized in that the first tank (140) is arranged on top on the roll frame on the drive side (100) and/or that the second tank (140) is arranged on top on the roll frame on the operating side (100).

12. The rolling stand (100) according to claim 9, characterized in that a first common low-pressure circuit with at least one first low-pressure pump (130-1) and with a first common tank (140-1) for the two oil film bearings of the upper back-up roll is provided on the drive side (100) and on the operating side (100), and that a second common low-pressure circuit with a second low-pressure pump (130-2) and with a second common tank (140-2) for the two oil film bearings of the lower back-up roll is provided on the drive side (100) and on the operating side (100).

13. The rolling stand (100) according to claim 12, characterized in that the first common tank (140-1) is arranged on top on the roll frame on the drive side (100) or on top on the roll frame on the operating side (100).

14. The rolling stand (100) according to claim 9, characterized in that each of the four oil film bearings (120) for the two back-up rolls is individually associated with its own low-pressure circuit with its own low-pressure pump (130-I, 130-II, 130-III and 130-IV) and its own tank (140-I, 140-II, 140-III and 140-IV).

15. A rolling mill (200) with a plurality of rolling stands (100) arranged sequentially in a line for rolling metallic rolling stock, characterized in that at least one of the rolling stands (100) comprises two back-up rolls each with two back-up roll journals (110), four chocks (120) in the form of oil film bearings, each with a cylindrical receiving space for the rotatable support of one of the back-up roll journals (110), wherein the chocks comprise in their interior at least one low-pressure supply conduit (122) for supplying coolant and/or lubricant into the receiving space and comprise at least one low-pressure discharge conduit (124) for removing the coolant and/or lubricant out of the receiving space, and at least one low-pressure circuit with a low-pressure supply lines (122) for connecting a tank (140) for the coolant and/or lubricant to the low-pressure supply conduit (122) of the chock, with low-pressure discharge lines (124) for connecting the low-pressure discharge conduit to the tank, and with at least one low-pressure pump (130) for delivering the coolant and/or lubricant into the low-pressure circuit, characterized in that a gear mechanism (150) is provided which is arranged on the roll face-remote side of at least one of the chocks for the rotational coupling of the at least one low-pressure pump (130) to the back-up roll journal (110) rotatably supported in the receiving space.

16. The rolling mill (200) according to claim 15, characterized in that the tanks (140) of the front rolling stands of the rolling mill (200) are filled with a first oil type, and that the tanks (140) of the rear rolling stands are filled with a second oil type.

Description

[0023] Seven figures are attached to the specification, in which:

[0024] FIG. 1 shows a first exemplary embodiment for the association of a tank with the oil film bearings of a rolling stand;

[0025] FIG. 2 shows a longitudinal cross-cross-section through a chock with a roll bearing supported in it with a first variant of the gear mechanism for driving the low-pressure pump in a first installed position;

[0026] FIG. 3 shows a longitudinal cross-cross-section through the chock with a roll bearing supported in it with a second variant of the gear mechanism for driving the low-pressure pump in a second installed position;

[0027] FIG. 4 shows a second exemplary embodiment for the association of the tanks with the oil film bearings of the rolling stand;

[0028] FIG. 5 shows a third exemplary embodiment for the association of the tanks with the oil film bearings of the rolling stand;

[0029] FIG. 6 shows a fourth exemplary embodiment for the association of the tanks with the oil film bearings of a rolling stand; and

[0030] FIG. 7 shows a rolling mill with a plurality of rolling stands.

[0031] The invention is described in detail below with reference to the cited figures in the form of exemplary embodiments. In all figures, the same technical elements are designated with the same reference numerals. The reference numeral 140 also represents all variants of the reference numeral, i.e. 140, 140, 140-1, 140-2, 140-I, 140-II, 140-III and 140-IV. The reference numeral 130 is treated analogously.

[0032] All FIGS. 1 and 4 to 7 show by way of example four-high rolling stands 100 each with a roll frame 100 on the drive side and a roll frame 100 on the operating side. Each rolling stand comprises two back-up rolls which are rotatably mounted with their four roll journals 110 in oil film bearings 120. Each oil film bearing 120 comprises low-pressure supply lines 122 and low-pressure discharge lines 124. The return flows are returned into the tank or the tanks 140; the inflows are fed from the particular tank. The two middle rolls are work rolls 180 which typically set a roll slot between which rolling stock is transported in the rolling direction R and is rolled. The two work rolls 180 are supported by an upper and a lower back-up roll.

[0033] According to FIGS. 2 and 3 the chocks 120, also called support housings, comprise a cylindrical, possibly also conical receiving space 126 in which the particular roll journals 110 of the back-up rolls are rotatably supported. The receiving space 126 can optionally be set by a bearing bush 128 which is arranged in the chock in a non-rotating manner. An annular slot is formed between the chock 120 or the bearing bush 128 and between the roll journal 110 or a journal bush 114 optionally placed on the roll journal, which slot is filled during the operation of the rolling stand with coolant and/or lubricant. In order to supply the annular slot with the coolant and/or lubricant, inlets and outlets for the coolant and/or lubricant are provided on the periphery of the receiving space 126 which represent on the receiving-space side the ends of the low-pressure inlet conduit and of the low-pressure outlet conduit. The low-pressure inlet conduit 122 typically enters into the receiving space in the region of a 90- or 270-position relative to the loading zone.

[0034] According to FIG. 1, a low-pressure circuit is associated with the rolling stand 100 in order to supply these low-pressure inlet conduits 122 in the chocks with the coolant and/or lubricant. The coolant and/or lubricant run preferably geodetically out of a tank 140 via at least one low-pressure inlet line 122 of the low-pressure circuit into the low-pressure inlet conduits 122 in the interior of the chocks. Low-pressure outlet conduits 124 can also be recognized in the chocks 120 adjacent to the low-pressure inlet channels 122 which outlet conduits are connected for their part by lines to the low-pressure outlet lines 124 running back into the tank. The low-pressure circuit comprises at least one low-pressure pump 130 for pumping the coolant and/or lubricant back at a low pressure, for example, 1 to 10 bar, preferably 2 bar, into the tank 140.

[0035] FIG. 2 shows a longitudinal cross-section through a chock 120 with a roll journal 110 of a back-up roll supported in it with a first variant of the gear mechanism according to the invention between the low-pressure pump and the roll journal. It can be concretely recognized that the low-pressure pump 130 is constructed in a recess 125 of the chock 120 in such a manner that its drive shaft 134 is aligned preferably parallel to the longitudinal axis of the back-up roll. The outwardly projecting, free end of the drive shaft 134 is preferably designed for its part as a gear or as a pinion or it is a pinion 152 mounted on this drive shaft in a non-rotating manner. In the first variant of the gear mechanism shown in FIG. 2, the pinion 152 or the gear on the drive shaft-side directly engages with an outside-toothing of gear ring 154 of a drive gear 154 which is mounted in a non-rotating manner coaxially on the roll face-remote side on the roll journal or on a journal bush 114 set on the roll journal. The gear mechanism 140 therefore consists in the present case of the pinion 152 and the drive gear 154 with gear ring 154 toothed on the outside which are in direct engagement with one another. Alternatively, the gear mechanism 150 could also provide an indirect coupling of pinion and drive gear, e.g., via a chain or other, intermediately connected gear mechanism gears. The shown inclusion of the low-pressure pump 130 in the recess 125 of the chock 120 represents a very compact construction, which is very advantageous for the basically always quite constricted spatial conditions in the surrounding area of rolling stands.

[0036] It can furthermore be recognized in FIG. 2 that the low-pressure pump 130 is connected on the input side to the low-pressure supply line 122. On the output side the low-pressure pump 130 pumps the coolant and/or lubricant via the low-pressure supply conduits 122 into the annular slot between the bearing bush 128 and the journal bush 114. The low-pressure supply conduits 122 are largely provided in the interior of the chock 120.

[0037] FIG. 3 shows a longitudinal cross-section through the chock 120 with the roll journal of the back-up roll supported in it. In distinction to FIG. 2, the low-pressure pump 130 is arranged here on the roll face-remote front side of the roll journal 110. The pinion 152 of the driving shaft 134 of the low-pressure pump is coupled here in a rotational manner to the roll journal 110, for example, via intermediate gears 156 with the drive gear 154 with the gear ring 154 toothed on the inside. The drive gear is preferably concentrically mounted in a non-rotating manner on the front side of the roll journal 110.

[0038] FIG. 4 shows another exemplary embodiment for the tank arrangement on or on top of the rolling stand 100. In concrete terms, according to this exemplary embodiment, a first common tank 140 is provided for the two oil film bearings 120 of the upper and of the lower back-up roll on the roll frame on the drive side 100. Furthermore, a second common tank 140 for the oil film bearing 120 of the upper and lower back-up roll is provided on the roll frame on the operating side 100 of the rolling stand 100. The first tank 140 is preferably arranged on top on the roll frame on the drive side 100, whereas the second comment tank 140 is arranged on top on the roll frame on the operating side 100.

[0039] According to FIG. 5, in another exemplary embodiment, a first common tank 140-1 is provided for the two oil film bearings 120 of the upper back-up roll on the drive side and the operating side of the rolling stand. Furthermore, a second common tank 140-2 is provided for the two oil film bearings 120 of the lower back-up roll on the drive side and the operating side. The first common tank 140-1 is preferably on top on the roll frame 100 on the drive side or on top on the roll frame 100 on the operating side of the rolling stand. The same preferably also applies to the second common tank 140-2.

[0040] FIG. 6 illustrates a third exemplary embodiment of the present invention, according to which the four oil film bearings 120 for the two back-up rolls are each individually associated with its own tank 140-I, 140-II, 140-III and 140-IV.

[0041] FIG. 7 shows a typical rolling mill for the hot and/or cold rolling of metallic rolling stock. It consists substantially of a plurality of rolling stands 100 set up sequentially in a line. According to the invention at least one of the rolling stands 100, but preferably all rolling stands, are constructed according to one of the previously described exemplary embodiments for a single rolling stand.

[0042] Care is to be taken in the arrangement of the rolling stands in a rolling mill that the front, i.e., the rolling stands located upstream in the direction of rolling typically apply a greater rolling force than the rear ones, i.e., the rolling stands located downstream. Therefore, the front rolling stands are typically designed for high carrying loads (T) to T=T.sub.SW with T.sub.SW: carrying load threshold value. In contrast thereto, the rear rolling stands are typically designed only for carrying loads with T<T.sub.SW; however, at the same time the rear rolling stands are designed for greater speeds. Based on these different operating conditions, the using of different oil types is recommended for the front and the rear rolling stands in the rolling mill. The using of different oil types was not possible at all until by the providing of individual tanks per rolling stand according to the invention.

[0043] These different operating conditions furthermore have the result that less oil must be stored for the front rolling stands than for the rear rolling stands; accordingly, the tank volume per rolling stand to be provided for the front rolling stands can be selected to be distinctly smaller than for the rapidly rotating rear rolling stands.

[0044] In concrete terms, it is provided that that the oil volume per rolling stand to be reserved in the decentralized oil supply according to the invention is reduced to one half compared to the traditional central oil supply. Therefore, the tank volume per stand to be reserved in the present invention is only 1-8 m.sup.3, i.e. in the case of 4 oil film bearings for rolling stand an amount of only 0.25-2 m.sup.3 per oil film bearing. The described fact that the front stands of the rolling mill only require a tank volume in the lower indicated range and only the rear rolling stands require a greater tank volume, results in an average value for the tank volume which corresponds according to the invention to less than 50% of the tank volume traditionally centrally reserved for a rolling mill.

[0045] In all exemplary embodiments the at least one low-pressure pump 130 can be built into the low-pressure supply line and/or in to the low-pressure discharge line as well as inside or outside of the chocks.

LIST OF REFERENCE NUMERALS

[0046] 100 rolling stand

[0047] 100 drive side

[0048] 100 operating side

[0049] 110 back-up roll journal

[0050] 114 journal bush

[0051] 120 chock

[0052] 122 low-pressure supply line

[0053] 122 low-pressure supply conduit

[0054] 124 low-pressure discharge line

[0055] 124 low-pressure discharge conduit

[0056] 125 recess in the chock

[0057] 126 receiving space or annular slot

[0058] 128 bearing bush

[0059] 130 low-pressure pump

[0060] 130, 130 low-pressure pump

[0061] 130-1, 130-2 low-pressure pump

[0062] 130-I . . . 130 IV low-pressure pump

[0063] 134 drive shaft of the low-pressure pump

[0064] 140 tank

[0065] 140, 140 tank

[0066] 140-1, 140-2 tank

[0067] 140-I . . . 140 IV tank

[0068] 150 gear mechanism

[0069] 152 pinion

[0070] 154 drive gear

[0071] 154 gear ring with external toothing

[0072] 154 gear ring with internal toothing

[0073] 156 intermediate gears

[0074] 180 work rolls

[0075] 200 rolling mill

[0076] R rolling direction

[0077] T carrying force

[0078] T.sub.SW carrying force threshold value