EP0309394B1 - Rolling mill stand or continuous-casting stand - Google Patents

Abstract

A rolling mill stand or continuous-casting stand for processing metals and non-metallic materials comprises a first, fixedly supported bearing housing (16) and a second bearing housing (18), which can be adjusted in order to alter a roll gap (10). These housings support the bearings of the rolls (12, 14). Recesses for accommodating the adjusting device for the roll gap are provided in the outer region of the mutually facing front faces. <??>Means (38) for pivoting the second bearing housing (18) about an axis (46) of rotation extending parallel to the axes (42, 44) of the rolls (12, 14) are arranged in one set of mutually facing recesses (36) while means (40) for adjusting the spacing of the bearing housings (16, 18) and hence the roll gap (10) are arranged in the other set of mutually facing recesses (36). <IMAGE>

Description

The invention relates to a prestressed stand for rolling or roll casting of metals in strip form with a first, fixed support and a second, adjustable for setting a roll gap bearing housing, which support the bearings of the rollers, each in the outer region of the facing end faces Bearing housing recesses are provided for receiving an adjusting device for the roll gap.

The conventional way of setting a roll gap is to clamp the rolls onto the plates on the one hand or to position the rolls via a spindle or a hydraulic cylinder, clamped in a roll stand. In the latter solution, the expansion of the roll stand always affects the roll gap, which leads to increased inaccuracy. Driving on solid plates offers no possibility of adjusting the roll gap during operation.

Similar solutions can be implemented with the state of the art known today by means of hydraulic electronic roll control systems. However, such systems are very complex and expensive and are therefore out of the question for economic reasons, especially for roll casting systems.

DE-A1-2646388 shows a strand guide on a casting plant with mutually opposite frame or scaffold parts connected by tie rods, in which the strand guide rollers are mounted. The casting gap, ie the distance between two casting rolls, is changed by inserting spacer plates and determining the distance between the bearing housings from each other. Calibrated plates are necessary for precise adjustment, which are based on the different chocks are matched. The fine adjustments usually have to be made with thin gauges. A correction of the casting gap during the operation of the casting system is completely impossible.

DE-A1-3238938 discloses a device according to the preamble of claim 1 for adjusting a gap formed by two rolls, in particular a casting gap of a roll casting installation for producing aluminum strips. The rollers are arranged in roller bearings surrounded by bearing housings. At least one of the bearing housings has, at its corner regions opposite the other bearing housing, in each case inclined surfaces at a certain angle with respect to an axis, which wedge surfaces of movable adjusting blocks bear against. The wedges can therefore be moved in the direction vertical to the roller axes.

US-A-4660400 describes a roll stand for the production of pipes and comprises work and support rolls arranged in pairs. After removing a locking bolt, an attachment with the upper support roller can be opened around a turning axis. The work rolls arranged in the housing can be lifted off together with the pedestals, replaced with new units and the attachment can be closed again. Preloading takes place in two separate stages: First the scaffold with eccentrics, whereby the attachment is rotated around the locking bolt removed when opening, then the work rolls themselves with other eccentrics, whereby the bearing blocks are pivoted about axes of rotation. The axes of the work rolls must be aligned with the help of wedges which can be moved with screws running parallel to the roll axes. Pressure transducers continuously monitor the pre-tension applied to the work rolls in the second stage.

DE-A1-3238936 describes a prestressable roll stand for producing rolled strips with at least two rolls mounted in holding frames. The holding frames are connected to each other by pre-tensioning devices from a hydraulic or pneumatic cylinder-piston system. The setting of the roll gap is not affected.

The inventor has set himself the task of creating a stand for rolling or roll casting of the type mentioned, which allows a further simplified adjustment of the roll gap for all types of stands, with stand housings clamped on one another or arranged in a stand, which at least maintains stability and creates opportunities for the use of electronic control and control with appropriately designed scaffolding.

The object is achieved according to claim 1.

In contrast to known devices, the distance between the bearing housings and thus the rollers is therefore not changed by parallel displacement of the second or upper bearing housing, but by its adjustable pivoting about a pivot axis.

The bearing housing with the means according to the invention for adjusting the roll gap can be used in stands of all known embodiments, for example in closed stands or in stands for opening. Scaffolds according to DE-A-32 38 936, which are described there for strip casting machines, have proven to be particularly advantageous. This scaffolding works according to the pretensioning principle, but with a column-less system.

When the bearing housing is clamped together with the first or second roller, which is the lower or upper roller in the normal position, the otherwise usual column expansion has no effect. This solution offers an optimal and rigid definition of the roll gap.

• Wenigstens ein Scharnier, gebildet aus einer Gabel, einer Zunge und einem darin gelagerten, entfernbaren Bolzen.
• Wenigstens zwei ineinanderliegende zylinderförmige oder wenigstens je zwei beidseits angeordnete, ineinanderliegende kugelförmige Gleitlager.

The means for forming a pivot axis of the second bearing housing running parallel to the axes of the rollers are preferably configured as follows:

• At least one hinge, formed from a fork, a tongue and a removable bolt mounted therein.
• At least two cylindrical slide bearings lying one inside the other or at least two spherical slide bearings arranged one on both sides.

The means for adjusting the roll gap essentially correspond to known means, which have hitherto been provided on both sides of the end faces of the bearing housing.

According to a first variant, interchangeable spacer plates are arranged in the corresponding cutouts, preferably corner cutouts. These plates must be slightly cambered at least on one side, because due to the different swivel positions not always a full surface Edition can arise. Interchangeable gauge plates can be added for fine adjustment. Both spacer plates and gauge plates are precisely calibrated. According to this first variant, the means for changing the distance between the bearing housings, the spacer plates and / or gauge plates cannot be exchanged under load, so automated operation is not an option here. In principle, therefore, non-prestressed scaffolding can also be equipped or retrofitted; however, these have the disadvantages mentioned with regard to the expansion under the action of force.

According to a second variant, the means for adjusting the roll gap with respect to the axis of rotation of the second bearing housing can be tangential spindles which can be rotated by hand or by machine.

According to a third variant, the means for adjusting the roll gap are designed as a hydraulic electronic roll gap control system. Like the spindle mentioned above, this can be operated automatically. A hydraulic electronic roller control system, however, is relatively complex and expensive according to the current state of the art.

According to a further variant, wedges which can be displaced relative to one another in the direction of the axes of the rollers with height adjustment are arranged in the corresponding recesses in the bearing housing. It has proven to be particularly advantageous to arrange double wedges which can be displaced by a spindle with screw threads of opposite pitch, as described in DE-A-32 38 938. Each of the two double wedges can be supported in a recess, in particular a corner recess. A comparison with this embodiment, which has proven itself in practice, makes the simplified embodiment according to the present invention particularly clear: only one has to be in the direction of the axes the spindle running spindles are rotated with two double wedges, while according to DE-OS 32 38 938 spindles with double wedges running on both sides of the end faces of the rollers in the transverse direction to the axes thereof, which must be exactly matched, are required. If a separate spindle is arranged for each bearing housing, these can be easily connected to a shaft.

Finally, according to a last-mentioned variant, the means for adjusting the roll gap can be flexible elements with a defined tension, which generate a counter pressure to a prestress and are therefore partially pressed into the working position, depending on the selected stiffness. This resilient element must be able to lift the upper roller with its bearings and the bearing housing when the preload is relieved. The flexible elements, which are preferably designed as spring elements, load cells or hydraulic elements, and which are interchangeable, are designed according to the preload pressure and the size of the roller force, as well as the desired adjustment range, and the characteristic curves are defined accordingly.

The means for adjusting the roll gap can be mounted on the inlet or outlet side of the stand, the means for pivoting the second bearing housing are arranged accordingly.

The adjustable means for changing the distance between the bearing housings can preferably be controlled and controlled in an electronic control circuit by means of displacement sensors of the roll gap and / or strip thickness detection.

The stand for rolling or roll pressing is used for metals.

- Fig. 1

eine teilweise aufgeschnittene Ansicht eines ständerlosen, vorgespannten Walzgerüstes für das Bandgiessen von Aluminium,

- Fig. 2

einen Vertikalschnitt mit Teilansicht eines Doppelkeils zur Einstellung des Walzspaltes,

- Fig. 3

ein Schnitt durch Fig. 2 gemäss der Linie III-III,

- Fig. 4

eine teilweise aufgeschnittene Ansicht zweier Lagergehäuse mit einem Hydraulikzylinder zum Schwenken des zweiten Lagergehäuses,

- Fig. 5

eine teilweise aufgeschnittene Ansicht zweier Lagergehäuse mit einer tangential wirkenden Spindel zum Schwenken des zweiten Lagergehäuses,

- Fig. 6

eine teilweise aufgeschnittene Ansicht zweier Lagergehäuse mit einem Scharnier zum Schwenken des zweiten Lagergehäuses,

- Fig. 7

eine teilweise aufgeschnittene Ansicht zweier Lagergehäuse mit einem zylinderförmigen Gleitlager zum Schwenken des zweiten Lagergehäuses,

- Fig. 8

eine teilweise aufgeschittene Ansicht zweier Lagergehäuse mit einem kugelförmigen Gleitlager zum Schwenken des zweiten Lagergehäuses,

- Fig. 9

eine teilweise aufgeschnittene Ansicht zweier verspannter Lagergehäuse mit einem Scharnier als Schwenkachse und einer Kombination einer Federeinheit mit einer Keilanstellung zur Veränderung des Walzspaltes,

- Fig. 10

eine Variante von Fig. 9, mit einer im Lagergehäuse integrierten Federeinheit,

- Fig. 11

eine Prinzipansicht eines Gerüsts zum Oeffnen,

- Fig. 12

eine Prinzipansicht eines zusammengesetzten Gerüsts,

- Fig. 13

eine Prinzipansicht eines geschlossenen Gerüsts, und

- Fig. 14

ein Blockschema einer integralen hydraulischen Walzspaltregelung.

The invention is explained in more detail using the exemplary embodiments shown in the drawing. They show schematically:

- Fig. 1

a partially cut-away view of a column-free, prestressed roll stand for the strip casting of aluminum,

- Fig. 2

a vertical section with partial view of a double wedge for adjusting the roll gap,

- Fig. 3

3 shows a section through FIG. 2 along the line III-III,

- Fig. 4

a partially cut-away view of two bearing housings with a hydraulic cylinder for pivoting the second bearing housing,

- Fig. 5

a partially cut-away view of two bearing housings with a tangentially acting spindle for pivoting the second bearing housing,

- Fig. 6

a partially cut-away view of two bearing housings with a hinge for pivoting the second bearing housing,

- Fig. 7

a partially cut-away view of two bearing housings with a cylindrical slide bearing for pivoting the second bearing housing,

- Fig. 8

a partially cut-away view of two bearing housings with a spherical plain bearing for pivoting the second bearing housing,

- Fig. 9

a partially cutaway view of two braced bearing housings with a hinge as a pivot axis and a combination of a spring unit with a wedge adjustment to change the roll gap,

- Fig. 10

9 shows a variant of FIG. 9, with a spring unit integrated in the bearing housing,

- Fig. 11

a schematic view of a scaffold to open,

- Fig. 12

a schematic view of an assembled scaffold,

- Fig. 13

a schematic view of a closed scaffold, and

- Fig. 14

a block diagram of an integral hydraulic roll gap control.

1, liquid metal can be introduced into the roll or casting gap 10 between the lower roll 12 and the upper roll 14 from the left or the right side from a nozzle, not shown, in the standless, prestressed stand of a roll casting machine according to FIG. 1. These rollers are largely covered by the first, here lower bearing housing 16 or by the second, here upper bearing housing 18.

The first bearing housing 16 lies on a flat support 20 and a support 22 with centering on a base plate 24, the latter support being designed in a known manner for applying "pass-line" corrections. The base plate 24 in turn is supported on the foundation 28 by a frame support 26.

The second bearing housing 18 protrudes yoke-like at the top and receives the cylinder rods 30 of a pretensioning device 32 on both sides. The tension is generated hydraulically in the cylinders 34, the necessary infrastructure known per se is not shown.

The means 38, explained in more detail below, for forming a pivot axis 46 of the second bearing housing 18 about an axis of rotation 46 running parallel to the axes 42, 44 of the rollers 12, 14 are arranged in cutouts 36 in the first and second bearing housings 16, 18. The means 40 shown in the following figures, also arranged in recesses 36, for adjusting the distance between the bearing housings 16, 18 and thus the roll gap 10 are designated by 40.

The embodiment shown in FIGS. 2 and 3 of a means 40 (FIG. 1) for adjusting the casting gap is fastened here in corner recesses of the bearing housing 16, 18. A support plate 48 is arranged on the first, lower bearing housing 16. On top of this lies an exchangeable spacer plate 50 which is slightly convex at the top - hardly recognizable in the figures. By inserting spacer plates of different thicknesses, the rough adjustment takes place, which cannot be changed during the rolling or casting-rolling process. Of course, the spacer plate can be omitted in the limit case. Instead of the spacer plate 50, other means for rough adjustment can be used, e.g. an also interchangeable resilient element in the form of a load cell or a mechanically or hydraulically acting spring element.

The intermediate plate 52 lying on the spacer plate 50 or directly on the support plate 48 carries the housing 54 for a double wedge 56, which corresponds in terms of structure and operation to the double wedge adjustment of DE-PS 32 38 938. According to the invention, however, the axis 58 of the spindle 60 does not run transversely to the axes 42, 44 of the rollers 12, 14, but parallel to it. The spindle has two screw threads with opposite pitch, whereby the wedges 56 can be moved together or apart. The base of the wedges 56 lies over the entire surface of a correspondingly designed surface of the housing 54 which is inclined at an angle α. The housing 54 is on the end face closed for the double wedge with a flange 62, which are fastened to the housing by means of screws 64 and receive pins 66 on the lower side.

The threaded spindle 60 can be rotated by means of a manually operated ratchet 68, shown in broken lines in FIG. 2. The scale 70 can be read for fine adjustment. However, the riddle can be replaced by an electric, hydraulic or pneumatic drive of a known type. This is particularly necessary for automated control. The screw 72 is used to fasten the double wedge setting to the second bearing housing 18. These screws 72 pass through the side walls 73 of the housing 54.

4, a cylinder housing 130 with a piston 132 is arranged in a corner recess of the lower bearing housing 16. A plate 134, which is arranged in the corresponding corner cutout of the upper bearing housing 18 and has a concave bearing surface, lies on the cambered piston. A hydraulic medium 138, for example a plastic mass, a grease or a hydraulic oil, can be pressed into the interior through a pipe socket 136 opening into the cylinder housing 130. For this, e.g. a known, not shown, manually or motor-operated pump used.

The means 38 for forming the pivot axis 46 consist of a cambered support plate 140 which is arranged in a recess in the lower bearing housing 16 and has a recess which effects centering. The support plate is arranged in the upper bearing housing 18.

Both bearing housings 16, 18 each have a bore 94, 96 for receiving a roll neck.

5 shows a further variant of the means 40 for adjustment of the roll gap, which contains a spindle 92 which is rotatable by hand or by motor means. Of course, the spindle 92 according to FIGS. 2 and 3 can also have two threads, the roll gap is then less finely adjustable with the same pitch of the thread.

The means 38 for forming the axis of rotation 46 correspond to those of FIG. 4.

The hinge 74 shown in FIG. 6 for pivoting the second bearing housing 18 essentially consists of a fork and a tongue which are penetrated by a bolt which can be locked in the longitudinal direction. The bolt has as little play as possible, particularly in the case of non-prestressed frameworks. The fork can be attached to the first or second bearing housing 16, 18, the tongue correspondingly to the other.

7 and 8 slide bearings 82 are shown for pivoting the second bearing housing 18, which have a bearing shell 84 with a cylindrical recess or a bearing shell 86 with a spherical recess. The counterpart 88 or 90 correspondingly has at least one partially cylindrical or spherical surface. Corresponding to the hinge 74 (FIG. 6), both types of individual parts can be attached to both bearing housings 16, 18.

The bearing housings 16, 18 with the openings 94, 96 for the roller bearings, which are also biased with the force F and are shown in FIGS. 9 and 10, show special embodiments for the means 40 for setting the roller gap, which are only indicated in FIGS.

The means 38 for pivoting the second bearing housing 8 about the pivot axis running parallel to the roller axes 42, 44 46 are only indicated, they correspond to Figs. 4-8.

The means 40 for adjusting the roll gap (10 in FIG. 1) consist of a spring unit 98 and a double wedge 56 according to FIGS. 2 and 3. The interchangeable spring unit 98 is used for rough adjustment, the double wedge 56 for fine adjustment.

The spring unit is partially pressed in by the force F of the preload. However, the spring unit is so strong that the upper roller with the upper bearing housing 18 is lifted off if the pretensioning force is removed.

In Fig. 10, the spring unit 98 is integrated in the lower bearing housing 16 and is also used for rough adjustment. A double wedge 56 is again arranged for fine adjustment.

The systems according to FIGS. 9 and 10 are particularly well suited for automatic regulation, wherein the pretensioning force F, the double wedge 56 and possibly the spring unit 98 can be set electronically controlled.

• Es kann mit sehr genauem Walzspalt gearbeitet werden, die Ausdehnung eines Walzgerüstes beeinflusst den Walzspalt nicht.
• Es können preisgünstige Vorspanngerüste eingesetzt werden.
• Alle Parameter können unter Last grob- und/oder feinstufig eingestellt werden.
• Ein einmal eingestellter Walzspalt kann beliebig oft wiederholt werden, da beim Abheben der Walzen die Anstellung nicht verändert wird.

With these variants, the advantages of the invention become particularly clear:

• It is possible to work with a very precise roll gap, the expansion of a roll stand does not affect the roll gap.
• Inexpensive pre-tensioning stands can be used.
• All parameters can be set roughly and / or finely under load.
• Once a roll gap has been set, it can be repeated as often as required as the position is not changed when the rollers are lifted off.

Figures 11-13 show examples with stand frames. 11 can be opened by removing at least one bolt 100. The assembled scaffold of Fig. 12 can be dismantled by removing connecting screws, not shown. 13 shows a scaffold delimited by a closed stand. In all the embodiments according to FIGS. 11-13, known means (not shown) for fastening or prestressing the bearing housing are arranged.

14 shows a standard control unit for rolling or casting and rolling stands, which also include the control and adjustment of the casting gap using the adjustable means according to the invention. The metal strip 104 of the roller system runs over deflection rollers through the work rollers 12, 14, which are each supported by a support roller 106. As already mentioned, scaffolds that are not prestressed or equipped with spacer plates cannot be operated with a control unit according to FIG. 14.

The devices and installations known per se shown in the diagram are provided with the following reference numbers: roll gap measuring device 110, strip thickness measuring device 111, strip speed measuring device 112, strip thickness control 113, roll gap control 114, position control 115, three-stage servo valve 116, pressure transmitter 117 (for hydraulic preloading), constant pressure control 118 , Skin pass level control 119 with laser 120, strip thickness control by strip tension control 121, strip tension controller 122, tension measuring cell for strip tension 123, address, data and control bus 124, operating and display panel 125, central unit 126, arithmetic processor 127 and EPROM RAM 128.

Claims (9)

1. Pretensioned stand for the rolling or roll casting of metals in strip form comprising a first fixedly supported bearing housing (16) and a second adjustable bearing housing (18) for adjusting a roll nip (10), said bearing housings supporting the bearings of the rolls (12, 14), and recesses (36) for receiving an adjusting device (38, 40) for the roll nip (10) being provided in the outer region of the opposing end faces of the bearing housings (16, 18), characterised in that in one of the opposing recesses (36) the adjusting device (38, 40) is provided with means (38) for the formation of a swivel axis (46) extending parallel to the axes (44, 42) of the rolls (12, 14) between the first and the second bearing housings (16, 18) and in the other of the opposing recesses (36) with means (40) for swivelling the second bearing housing (18) about the swivel axis (46) for adjusting the roll nip.
2. Stand according to claim 1, characterised in that the means (38) for swivelling the second bearing housing (18) consist of a hinge (74).
3. Stand according to claim 1, characterised in that the means (38) for swivelling the second bearing housing (18) consist of interlocking slide bearings (82).
4. Stand according to one of claims 1 - 3, characterised in that the means (40) for adjusting the roll nip (10) are interchangeable spacer plates (50) convex on at least one side, preferably complemented by interchangeable thin gauge plates for fine adjustment.
5. Stand according to one of claims 1 - 3, characterised in that the means (40) for adjusting the roll nip (10) with respect to the pivot axis (46) of the second bearing housing (18) are tangentially operating spindles (92) or hydraulically actuated pistons (132) in cylindrical housings (130).
6. Stand according to one of claims 1 - 3, characterised in that the means (40) for adjusting the roll nip (10) are displaceable wedges arranged in the direction of the axes (42, 44) of the rolls (12, 14), preferably double wedges (65) actuated by a spindle (60) having screw threads of opposite pitch.
7. Stand according to one of claims 1 - 3 or 6, characterised in that the means (40) for adjusting the roll nip (10) are flexible elements (98) generating a counterpressure to the pretension, which, partially compressed, lift the upper roll (14) when unloaded with respect to the pretensioning.
8. Stand according to claim 7, characterised in that the flexible elements are interchangeable spring elements, load cells or hydraulic elements.
9. Stand according to one of claims 5 - 8, characterised in that the pretensioning device (32) and/or the means (40) for adjusting the roll nip (10) and/or the flexible elements (98) can be monitored and controlled by means of displacement transducers for the roll nip and/or strip thickness detection in an electronic control circuit.

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