Abstract: The invention relates to a hydraulic actuator (1) that can be controlled by a main valve (2) and an auxiliary valve (3). Upstream of the main valve device (2) is a main regulator (7), having a P block (9) and an I block (10). Upstream of the auxiliary valve (3) is an auxiliary regulator (8), having a base block (11) and an I block (12). In a normal mode of operation, the auxiliary valve (3) is deactivated. The main regulator is provided with a main setpoint variable (p*) and a corresponding main actual quantity (p) of the hydraulic actuator (1). The main regulator (7) determines a main actuating variable (s) and predefines the main actuating variable (s) in the main valve device (2). In a special mode of operation, the base block (11) of the auxiliary regulator (8) is provided with an auxiliary setpoint variable (a*) and a corresponding auxiliary actual quantity (p) of the hydraulic actuator (1).

Abstract: A method is disclosed for actuating a tandem roll train, in particular a cold-strip tandem roll train, for producing a strip, e.g., a metal strip, wherein a plurality of drives are provided in a production direction of the strip, the speeds of which drives are adapted via cascade control by way of a master drive, wherein a property of the strip is determined and the direction of action of the cascade control is changed depending on said property, by a control factor (K) being provided, by way of which the direction of action of the cascade control is changed, wherein 0?K?1, and wherein if 0<K<1 the action direction is split proportionally between upstream cascading and downstream cascading.

Abstract: The invention relates to a hydraulic actuator (1) that can be controlled by a main valve (2) and an auxiliary valve (3). Upstream of the main valve device (2) is a main regulator (7), having a P block (9) and an I block (10). Upstream of the auxiliary valve (3) is an auxiliary regulator (8), having a base block (11) and an I block (12). In a normal mode of operation, the auxiliary valve (3) is deactivated. The main regulator is provided with a main setpoint variable (p*) and a corresponding main actual quantity (p) of the hydraulic actuator (1). The main regulator (7) determines a main actuating variable (s) and predefines the main actuating variable (s) in the main valve device (2). In a special mode of operation, the base block (11) of the auxiliary regulator (8) is provided with an auxiliary setpoint variable (a*) and a corresponding auxiliary actual quantity (p) of the hydraulic actuator (1).

Abstract: A roll mill for rolling a product has a roll stand with working rolls and a control device. The product has a head part and is moved towards the stand at a product head part speed. The working rolls form a rolling gap. The control device controls the stand such that, before the product head part enters the gap, the rolls are rotated at a peripheral speed which is essentially the same as the product head part speed; the gap is vertically adjusted to essentially a product head part thickness, on the feeding side, before the product enters the gap; and, during or following the insertion of the product into the gap, the gap is closed to a pre-determined value, and the peripheral speed of the working rolls is modified, especially increased, according to the gap, essentially at the same time as the closing of the gap.

Abstract: In mill stands of a continuous rolling train, a product passes through the train is rolled such that the product upon leaving the train has predetermined final characteristics. To remove one of the stands, the mill stand to be removed is completely relieved of load according to a defined temporal load relieving sequence. Locally simultaneously with the load relieving, at least one other mill stand is placed under load according to a defined temporal loading sequence. The load-relieving and loading sequence are mutually adjusted to preserve the final product characteristics. A circumferential roll velocity is controlled until the stand has been completely relieved such that a discharge velocity corresponds always to a predetermined desired discharge velocity. After the complete load-relieving, a correspondence of the circumferential roll velocity to the desired discharge velocity is maintained and the working rolls are lifted off. The mill stand is then deactivated.

Abstract: In a method for cooling a hot strip wound to a hot strip bundle, a device for cooling a hot strip bundle, a control and/or regulating device, and a metal strip, the hot strip bundle (1) is twisted (100) and cooled by contact of the lateral surface (5) thereof with at least one element (3, 7). By twisting the hot strip bundle (1) about the axis of symmetry (S) thereof, a method and a device can be provided by which homogenous strip properties may be obtained for a cooling hot strip bundle in a compact manner.

Abstract: A method is disclosed for actuating a tandem roll train, in particular a cold-strip tandem roll train, for producing a strip, e.g., a metal strip, wherein a plurality of drives are provided in a production direction of the strip, the speeds of which drives are adapted via cascade control by way of a master drive, wherein a property of the strip is determined and the direction of action of the cascade control is changed depending on said property, by a control factor (K) being provided, by way of which the direction of action of the cascade control is changed, wherein 0?K?1, and wherein if 0<K<1 the action direction is split proportionally between upstream cascading and downstream cascading.

Abstract: In a multi-staged cold-rolling line, a strip is rolled. An actual rolling force of a last rolling stage of the cold-rolling line is detected and fed to a force control unit which determines a control parameter using the actual rolling force and a target rolling force and outputs a control parameter. An actual thickness is detected directly downstream of the last rolling stage and is sent to a thickness control unit which acts on the last rolling stage. Another actual strip thickness is detected directly upstream of the last rolling stage. Enter and exit speeds of the last rolling stage are detected and with a pre-determined final strip thickness following the last rolling stage fed to a setpoint determination unit which determines a target thickness which is used as a setpoint for another thickness control unitacting on the next to last rolling stage and receiving the other actual thickness value.

Abstract: A cold-rolling train has a plurality of rolling stands and a strip feeding device to which an initial setpoint speed is sent to feed the cold strip to the first stand at an initial actual speed corresponding to the initial setpoint speed. A first setpoint speed is sent to the first stand so that associated rolls rotate. Between the first and next passed-through rolling stand is a thickness detection device detecting a first actual thickness. A base output signal is determined using the first actual and setpoint thicknesses and is used to adjust the first setpoint speed, but not the initial setpoint speed, conforming the first actual to the first setpoint thickness. Between the feeding device and the first rolling stand is an initial thickness detection device detecting an initial actual thickness. The initial setpoint speed is adjusted by a initial feed-forward controller to adjusted a setpoint product mass flow.

Abstract: A regulation device (7) for a rolling stand (2) has a force regulator (8) and a position regulator (9) mounted underneath the force regulator. During operation of the regulation device, a rolling force target value (F*) and a rolling force actual value (F) are supplied to the force regulator (8). A regulating distance correcting value (ds1*) is determined by the force regulator (8) from the rolling force target value (F*) and the rolling force actual value (F). The regulating distance correcting value (ds1*), an excentricity compensation value (ds2*), and a regulating distance actual value (s) of a regulating element (6) are supplied to the position regulator (9). A correcting quantity (dq) is determined by the position regulator (9) from the values (ds1*, ds2*, s) supplied thereto and is delivered to the regulating element (6). The regulating distance of the regulating element (6) is changed according to the correcting quantity (dq).

Abstract: A strip is fed a rolling stand of a multi-stand rolling mill with a known inlet thickness and exits with a strip thickness. Measurement parameters are determined that are characteristic of the inlet-side and outlet-side strip velocities. With the measurement parameters, the inlet-side and outlet-side strip velocities are determined with respect to the rolling stand. With the inlet thickness, the inlet-side and outlet-side strip velocities, the strip thickness is determined with respect to the rolling stand. Taking into account the determined strip thickness, further measures are taken. The measurement parameter for the inlet-side velocity is the roller peripheral velocity directly prior to the rolling stand. Alternatively or in addition, the measurement parameter for the outlet-side velocity is the roller peripheral velocity. The peripheral precession of the strip is modeled.

Abstract: In a method for cooling a hot strip wound to a hot strip bundle, a device for cooling a hot strip bundle, a control and/or regulating device, and a metal strip, the hot strip bundle (1) is twisted (100) and cooled by contact of the lateral surface (5) thereof with at least one element (3, 7). By twisting the hot strip bundle (1) about the axis of symmetry (S) thereof, a method and a device can be provided by which homogenous strip properties may be obtained for a cooling hot strip bundle in a compact manner.

Abstract: In mill stands of a continuous rolling train, a product passes through the train is rolled such that the product upon leaving the train has predetermined final characteristics. To remove one of the stands, the mill stand to be removed is completely relieved of load according to a defined temporal load relieving sequence. Locally simultaneously with the load relieving, at least one other mill stand is placed under load according to a defined temporal loading sequence. The load-relieving and loading sequence are mutually adjusted to preserve the final product characteristics. A circumferential roll velocity is controlled until the stand has been completely relieved such that a discharge velocity corresponds always to a predetermined desired discharge velocity. After the complete load-relieving, a correspondence of the circumferential roll velocity to the desired discharge velocity is maintained and the working rolls are lifted off. The mill stand is then deactivated.

Abstract: In a multi-staged cold-rolling line, a strip is rolled. An actual rolling force of a last rolling stage of the cold-rolling line is detected and fed to a force control unit which determines a control parameter using the actual rolling force and a target rolling force and outputs a control parameter. An actual thickness is detected directly downstream of the last rolling stage and is sent to a thickness control unit which acts on the last rolling stage. Another actual strip thickness is detected directly upstream of the last rolling stage. Enter and exit speeds of the last rolling stage are detected and with a pre-determined final strip thickness following the last rolling stage fed to a setpoint determination unit which determines a target thickness which is used as a setpoint for another thickness control unitacting on the next to last rolling stage and receiving the other actual thickness value.

Abstract: A strip is fed a rolling stand of a multi-stand rolling mill with a known inlet thickness and exits with a strip thickness. Measurement parameters are determined that are characteristic of the inlet-side and outlet-side strip velocities. With the measurement parameters, the inlet-side and outlet-side strip velocities are determined with respect to the rolling stand. With the inlet thickness, the inlet-side and outlet-side strip velocities, the strip thickness is determined with respect to the rolling stand. Taking into account the determined strip thickness, further measures are taken. The measurement parameter for the inlet-side velocity is the roller peripheral velocity directly prior to the rolling stand. Alternatively or in addition, the measurement parameter for the outlet-side velocity is the roller peripheral velocity. The peripheral precession of the strip is modeled.

Abstract: A cold-rolling train has a plurality of rolling stands and a strip feeding device to which an initial setpoint speed is sent to feed the cold strip to the first stand at an initial actual speed corresponding to the initial setpoint speed. A first setpoint speed is sent to the first stand so that associated rolls rotate. Between the first and next passed-through rolling stand is a thickness detection device detecting a first actual thickness. A base output signal is determined using the first actual and setpoint thicknesses and is used to adjust the first setpoint speed, but not the initial setpoint speed, conforming the first actual to the first setpoint thickness. Between the feeding device and the first rolling stand is an initial thickness detection device detecting an initial actual thickness. The initial setpoint speed is adjusted by a initial feed-forward controller to adjusted a setpoint product mass flow.

Abstract: A roll mill for rolling a product has a roll stand with working rolls and a control device. The product has a head part and is moved towards the stand at a product head part speed. The working rolls form a rolling gap. The control device controls the stand such that, before the product head part enters the gap, the rolls are rotated at a peripheral speed which is essentially the same as the product head part speed; the gap is vertically adjusted to essentially a product head part thickness, on the feeding side, before the product enters the gap; and, during or following the insertion of the product into the gap, the gap is closed to a pre-determined value, and the peripheral speed of the working rolls is modified, especially increased, according to the gap, essentially at the same time as the closing of the gap.

Abstract: A regulation device (7) for a rolling stand (2) has a force regulator (8) and a position regulator (9) mounted underneath the force regulator. During operation of the regulation device, a rolling force target value (F*) and a rolling force actual value (F) are supplied to the force regulator (8). A regulating distance correcting value (ds1*) is determined by the force regulator (8) from the rolling force target value (F*) and the rolling force actual value (F). The regulating distance correcting value (ds1*), an excentricity compensation value (ds2*), and a regulating distance actual value (s) of a regulating element (6) are supplied to the position regulator (9). A correcting quantity (dq) is determined by the position regulator (9) from the values (ds1*, ds2*, s) supplied thereto and is delivered to the regulating element (6). The regulating distance of the regulating element (6) is changed according to the correcting quantity (dq).

Abstract: The invention relates to a method for rolling a product in a rolling train comprising at least two roll stands having a roll gap, the product to be rolled comprising a transition region. If a critical transition region crosses the rolling train, the roll gaps of the roll stands are successively opened and closed according to the position of the transition region moving at speed through the rolling train, in the direction of the direction of travel of the conveyor. The opening of the roll gaps occurs parallel to the position of the critical transition region when the product is displaced. A transition region is critical when the structure requires the roll gaps to be opened. The inventive opening of the roll gaps, when the device is moving, enables the controlled transition of a product to be rolled with extreme variations in dimensions and/or hardness, for a shorter length.

Abstract: In a control system, especially a hydraulic screw-down control system for a roll stand, the controller output is acted upon by a pilot control value (v.sub.1.sup.*). At the same time, a reference value (x.sub.M ') is delivered to the controller via a subtractor as a setpoint value. The reference value (x.sub.m ') is determined in a model control loop based on the pilot controller. Parasitic response characteristics of the overall system are largely accounted for in the model control loop, so that on a time-averaged basis the controller is not activated.