A measurement device for measuring properties of a metal sheet processed in a rolling mill, including: an inspection coil set including a transmitter coil and a receiver coil, the transmitter coil being configured to apply a time-varying magnetic field to the metal sheet, and the receiver coil being configured to detect a magnetic field transient produced from the metal sheet. The property of the metal sheet is derivable from the magnetic field transient. A correction coil set, for detecting a spatial deviation of the metal sheet from a reference plane, each correction coil being connectable to a capacitor to form a respective resonance circuit having a resonance frequency. The correction coils are resonated at the respective resonance frequency. A shift in the resonance frequency in the presence of the metal sheet is detectable and the spatial deviation is derivable from the shifts.

The present disclosure provides a strip flatness prediction method considering lateral spread during rolling. The method includes: step 1: acquiring strip parameters, roll parameters and rolling process parameters; step 2: introducing a change factor of a lateral thickness difference before and after rolling and a lateral spread factor by considering lateral metal flow, and constructing a strip flatness prediction model based on the coupling of flatness, crown and lateral spread; step 3: constructing a three-dimensional (3D) finite element model (FEM) of a rolling mill and a strip, simulating strip rolling by the 3D FEM, extracting lateral displacement and thickness data of the strip during a stable rolling stage, calculating parameters of the strip flatness prediction model based on the coupling of flatness, crown and lateral spread; and step 4: predicting the flatness of the strip by the strip flatness prediction model based on the coupling of flatness, crown and lateral spread.

A method that includes moving a sheet material between first and second groups of rolls following a winding path according to a setpoint speed, driving the first group of rolls by a first drive, driving the second group by a second drive independent of the first drive, measuring the speed of the first drive, measuring the speed of the second drive controlling the speed of the first drive by means of a first torque setpoint signal which is a function of a first error signal obtained from the difference between the setpoint speed and the speed of the first drive, and controlling the speed of the second drive by means of a second torque setpoint signal which is a function of a second error signal obtained from the difference between the setpoint speed and the speed of the second drive, and is also a function of an additional torque gain.

A method that includes moving a sheet material between first and second groups of rolls following a winding path according to a setpoint speed, driving the first group of rolls by a first drive, driving the second group by a second drive independent of the first drive, measuring the speed of the first drive, measuring the speed of the second drive controlling the speed of the first drive by means of a first torque setpoint signal which is a function of a first error signal obtained from the difference between the setpoint speed and the speed of the first drive, and controlling the speed of the second drive by means of a second torque setpoint signal which is a function of a second error signal obtained from the difference between the setpoint speed and the speed of the second drive, and is also a function of an additional torque gain.

A method for detecting a faulty cooling unit in a set of cooling units configured to provide a coolant to work rolls arranged to process a work item therebetween, the method including: varying the flow rates of the coolant ejected from a sub-set of the cooling units; in response to varying the flow rates, determining a flatness variation value of the work item for at least each of the cooling units in the sub-set of cooling units, the flatness variation value being indicative of the work item flatness variation downstream of the work rolls; and detecting a faulty cooling unit based on comparing the flatness variation values to a reference flatness variation value.

An apparatus for detecting an edge crack of a metal plate being conveyed includes: a detection part including a plurality of elements configured to detect a presence or absence of the metal plate at a position of the element in the plate width direction; a plate edge position determination part configured to determine a plate edge position of the metal plate in the plate width direction on the basis of a detection result of each of a plurality of first elements positioned within a first region in the plate width direction; and an edge crack detection part configured to detect an edge crack of the metal plate on the basis of a detection result of each of a plurality of second elements selected on the basis of the plate edge position and positioned within a second region which is narrower than the first region in the plate width direction.

An apparatus for detecting an edge crack of a metal plate being conveyed includes: a detection part including a plurality of elements configured to detect a presence or absence of the metal plate at a position of the element in the plate width direction; a plate edge position determination part configured to determine a plate edge position of the metal plate in the plate width direction on the basis of a detection result of each of a plurality of first elements positioned within a first region in the plate width direction; and an edge crack detection part configured to detect an edge crack of the metal plate on the basis of a detection result of each of a plurality of second elements selected on the basis of the plate edge position and positioned within a second region which is narrower than the first region in the plate width direction.

A method for detecting a faulty cooling unit in a set of cooling units configured to provide a coolant to work rolls arranged to process a work item therebetween, the method including: varying the flow rates of the coolant ejected from a sub-set of the cooling units; in response to varying the flow rates, determining a flatness variation value of the work item for at least each of the cooling units in the sub-set of cooling units, the flatness variation value being indicative of the work item flatness variation downstream of the work rolls; and detecting a faulty cooling unit based on comparing the flatness variation values to a reference flatness variation value.

A meandering control method for steel strip includes: an imaging step of imaging the surface of a traveling steel strip using a line sensor camera installed between adjacent rolling mills; a meandering amount calculation step of calculating the meandering amount of the steel strip by detecting the positions of both end portions in the width direction of the steel strip from a one-dimensional brightness distribution based on the captured image; and a leveling control arithmetic operation step of arithmetically operating a roll opening difference between the operation and drive sides of the rolling mill located on the immediately downstream side of the line sensor camera based on the calculated meandering amount. The imaging is performed in a period of 5 msec or less.

In a method for the online determination of at least one rolling parameter when rolling a rolling material rolled along a rolling line in a rolling mill including at least two rolls on a roll stand, the rolling material is guided past or through at least one measuring device during the rolling, which interacts with a rolling material variable of the rolling material, the rolling material variable being changeable along the length of the rolling material, and outputs a measurement signal, wherein: (i) the measurement signal is transferred into the frequency space, and the rolling parameter is determined from the measurement signal transferred into the frequency space, and/or (ii) a frequency inherent in the change of the rolling material variable is determined from the measurement signal, and the rolling parameter is determined on the basis of the determined frequency.