DE10102037A1 - Control of working rollers with slight horizontal yaw in multiple-roller stand, measures axial roller force, signaling if excessive - Google Patents

Abstract

Axial forces (F) are exerted by one or more rollers (3, 4, 5). Preferably the force exerted by the working roller (5) against its bearing housing is measured. The value is sent to an analyzer (7) comparing it with a predetermined maximum (F max) in memory. Should this be exceeded, a signal is given. An independent claim is included for the corresponding control system.

Description

The invention relates to a method for controlling or regulating the Rolling of rolling stock in a single or multi-stand rolling mill, where one or more duo, quarto or sexto frames with support, intermediate or Work rolls are used in which at least two work rolls cooperatively roll the rolling stock to be machined and at least one, preferably two, work rolls opposite the vertical to Direction of conveyance of the rolling stock by a small swivel angle in the Horizontal plane are pivoted, with means are provided with which the Swivel angle can be adjusted.

Furthermore, the invention relates to a device for control or regulation the rolling process of rolling stock in a single or multi-stand rolling mill.

The generic rolling method is known in the production of steel, that is in the area of steel rolling mills. When rolling a slab between two work rolls, it can occasionally be observed that an undesired waviness forms on the rolling stock or that the rolling stock has insufficient dimensional stability, which is caused by the rolling process. It has been found that a quality improvement can be achieved by pivoting the work rolls - and with them possibly also the support and intermediate rolls - by a slight swivel angle in the horizontal plane of the rolled stock compared to the perpendicular to the conveying direction of the rolled stock. A value less than 1 ° is usually sufficient as the swivel angle. Regarding the state of the art, reference is made to the Mitsubishi Pair Cross Mill company lettering from Mitsubishi Heavy Industries, Ltd., Tokyo, Japan. In the method described there, the two work rolls, which contact the rolling stock, are each rotated relative to one another by the said swivel angle, so that the roll center lines form an "X" in plan view. For this purpose, reference is made to FIG. 2 of the description.

It has been found that with the generic method a significant quality improvement can be achieved. However, at Application of the method also a much stronger storage of the Rolling is required because of the pivoting between the roller and the rolling stock Force is generated perpendicular to the conveying direction of the rolling stock in the storage the roller produces an eel force. So that it is necessary Dimension roller bearings so that they absorb significantly higher forces can. This makes the storage systems for the rollers considerably more expensive.

It is particularly problematic that it is very difficult to reliable predictions about the magnitude of the resulting axial force do. As a result, the bearings are either very oversized be what is disadvantageous in terms of cost, or that the bearings due to large forces are overused, which leads to premature failure or the remodeling parts wear excessively.

The invention is therefore based on the object, a method and a associated device for controlling or regulating the rolling process To propose the use of the generic method with which it is possible to rule out overdimensioning of the roller bearings as well  Ensure that the bearings and the conversion parts (e.g. locks) the have the required service life. It should therefore be ensured that the Roller bearings can only be operated up to the permissible load.

This object is achieved by the invention in that the method has the following steps:

• a) measuring the axial force, at least one of the rollers, preferably the Work roll on which this bearing housing exerts;
• b) supplying the measured value of the axial force to a evaluation;
• c) Comparison of the measured value with a stored one predetermined maximum value;
• d) triggering a signal as soon as the measured value reaches the stored one exceeds the specified value.

The proposal according to the invention is based on the fact that in one Roll mill stand, the axial force between the roll and the housing is determined consequently must be taken up by the storage of the roll neck. The The measured axial force value is constantly with a predetermined maximum value compared, and action is taken once the predetermined value.

In the simplest case, according to a further development, the signal is on Warning signal is. In this case it can be done by acoustic, optical or other means The system issues a warning that the permissible axial force in the bearing is exceeded.  

As an alternative and preferred, however, there is also the question of direct disposal the fault occurs in that a closed loop The swivel angle is canceled. In particular, it is provided that the Signal influence the means for adjusting the swivel angle so that a a lower swivel angle is set, which produces an eel force that is below the specified value.

In large systems, it can be advantageous to measure the value of the eel force to transmit wirelessly, preferably an inductive transmission or a such can be envisaged by radio.

The device for controlling or regulating the rolling process of rolling stock has means with which one, preferably two, work rolls can be swiveled by a small swivel angle in the horizontal plane with respect to the perpendicular to the conveying direction of the rolling stock. The proposal according to the invention is characterized by
at least one sensor for measuring the eel force applied by the roller to the housing supporting it,
an evaluation unit for comparing the measured eel force with a predetermined maximum value and
Means for generating and / or outputting a signal as soon as the measured value exceeds the stored predetermined value.

The proposed measures ensure that a too large Rise in the axial force in the roll neck bearing due to an oversized Swing angle does not remain undetected, but immediately for initiation countermeasures leads. It can thus be achieved that a  Overuse of the bearings is excluded and consequently the service life of the Storage is increased significantly.

In the drawing, an embodiment of the invention is shown. Show it:

Fig. 1 shows diagrammatically a cross section through a six-high stand of a rolling mill,

Fig. 2 shows schematically the top view of the six-high structure, but only the two work rolls are shown.

In Fig. 1, a six-high stand is shown in a rolling mill train 2, is rolled in the rolling stock 1. The rolling stock 1 is transported in the conveying direction R. For this purpose, the stand 2 has a total of six rollers 3 , 4 , 5 which roll on one another or on the rolling stock 1 . The work rolls 5 are connected to the intermediate rolls 4 ; these in turn interact with the support rollers 3 .

Fig. 2 shows the plan view on the slab to be rolled 1, the two work rolls 5 are outlined. To improve the quality, the two work rolls 5 do not run parallel to one another, but are pivoted by a slight pivot angle α relative to the vertical S onto the conveying direction R in the horizontal plane H. Means 6 , which are schematically outlined here as piston-cylinder units, are used to set the swivel angle α. The swivel angle α can be changed by means of the setting means 6 . As a rule, it is sufficient to provide a swivel angle α smaller than 1 ° in order to produce the desired effect, namely to reduce the waviness of the rolling stock 1 or to improve the dimensional stability of the rolling stock 7 . It is not shown that the intermediate or support rollers 3 , 4 correspond to the pivoting angle α, so that the work, intermediate and support rollers are parallel to each other with respect to their axis of rotation.

The setting of a pivoting angle a not equal to zero means that the work roll 5 experiences a lateral pushing force perpendicular to the conveying direction R when the rolling stock 1 is rolled. This axial force F must be absorbed by the roll neck bearing (not shown). A sensor 8 of known type is arranged in the bearing, with which it is possible to determine the axial force between the roller 5 and the housing. In the exemplary embodiment, the axial force value F measured by the sensor 8 is sent to the evaluation device 7 via a wireless signal transmission unit 11 . The maximum value for the axial force F _{max is} stored in the device 7 . It can therefore be used to make a comparison between the actual value F and the maximum value F _max . As long as the measured value F is less than the maximum value F _max , no measures are necessary. However, if the permissible value F _{max is} exceeded, the regulating or control device 9 initiates a measure. In the simplest case, an acoustic signal generator 10 , for example, is activated, so that the operating personnel are made aware that excessive axial force values are generated in the roll neck bearing. Care can then be taken to ensure that the axial force is reduced by reducing the swivel angle α, so that there is no overstressing of the bearings or wear on the conversion parts.

Preferably, however, the regulating or control device 9 can act directly on the means 6 for setting the swivel angle α: If the value for the current axial force F is too large, the means 6 can be used to reduce the swivel angle α, so that in FIG consequently the axial force F is also reduced. The swivel angle α can thus be set in the closed control loop in such a way that a maximum limit F _max for the axial force is not exceeded.

LIST OF REFERENCE NUMBERS

1

rolling

2

Scaffolding in a rolling mill

3

supporting roll

4

intermediate roll

5

Stripper

6

Means for adjusting the swivel angle

7

evaluation

8th

sensor

9

Regulation or control device

10

acoustic signal generator

11

wireless signal transmission unit
α swivel angle
S vertical
R conveying direction
H horizontal plane
F axial force
F _max

maximum axial force

Claims (7)

1. A method for controlling or regulating the rolling process of rolling stock ( 1 ) in a single or multi-stand rolling mill, one or more duo, quarto or sextoy stands ( 2 ) with support ( 3 ), intermediate ( 4 ) or work rolls ( 5 ) are used,
cooperating in the at least two work rolls ( 5 ), rolling the rolling stock ( 1 ) to be processed and
in which at least one, preferably two, work rolls ( 5 ) are swiveled by a small swivel angle (α) in the horizontal plane (H) with respect to the vertical (S) to the conveying direction (R) of the rolling stock ( 1 ),
means ( 6 ) are provided with which the swivel angle (α) can be set,
characterized by
that the process comprises the steps:

• a) measuring the axial force (F), which exerts at least one of the rollers ( 3 , 4 , 5 ), preferably the work roller ( 5 ), on the housing which supports it;
• b) supplying the measured value of the axial force (F) to an evaluation device ( 7 );
• c) comparison of the measured value (F) with a stored predetermined maximum value (F _max );
• d) triggering a signal as soon as the measured value (F) exceeds the stored predetermined value (F _max ).

2. The method according to claim 1, characterized in that the signal Warning signal is. 3. The method according to claim 1, characterized in that the signal influence the means ( 6 ) for adjusting the swivel angle (α) so that a lower swivel angle (α) is set, which causes an axial force (F) which is below the predetermined Value (F _max ). 4. The method according to any one of claims 1 to 4, characterized in that the measured value (F) is transmitted wirelessly. 5. The method according to claim 4, characterized in that the wireless Transmission takes place by induction.   6. The method according to claim 4, characterized in that the wireless Radio transmission.   7. Device for controlling or regulating the rolling process of rolling stock ( 1 ) in a single or multi-stand rolling mill, one or more duo, quarto or sexto stands ( 2 ) with support ( 3 ), intermediate ( 4 ) or work rolls ( 5 ) are used,
has the means ( 6 ) with which one, preferably two, work rolls ( 5 ) can be swiveled by a small swivel angle (α) in the horizontal plane (H) relative to the perpendicular (S) to the conveying direction (R) of the rolling stock ( 1 ) .
marked by
at least one sensor ( 8 ) for measuring the axial force (F) applied by the roller ( 3 , 4 , 5 ) to the housing supporting it,
an evaluation unit ( 7 ) for comparing the measured axial force (F) with a predetermined maximum value (F _max ) and
Means ( 9 , 10 ) for generating and / or outputting a signal as soon as the measured value (F) exceeds the stored predetermined value (Fmax).