A flatness measuring apparatus for measuring the flatness of a metallic strip, including a measuring roller which has a roller axis and which makes contact with the strip for the measuring the flatness. The measuring roller is connected to a cooling system, using which the measuring roller can be cooled. To ensure that a high degree of measuring accuracy can be maintained even at high temperatures, the cooling system has a nozzle bar that extends parallel to the roller axis. At least one spray nozzle is arranged on the nozzle bar, using which cooling medium can be sprayed on the surface of the measuring roller in a spraying direction. The spraying direction meets a surface section of the measuring roller, and the angle between the spraying direction and the tangent on the measuring roller at the location of the surface section is less than 30?.

A method is provided for cooling sheet metal using a cooling section having multiple coolant dispensing devices for cooling upper and lower faces of a sheet metal. The cooling achieves a predefined target state of the sheet metal at a reference point at and/or after the exit from the cooling section, wherein coolant dispensing for a first and a second coolant dispensing device is determined, wherein the first and the second coolant dispensing devices are arranged opposite the sheet metal. Because the coolant dispensing for the first and second coolant dispensing devices is determined based on a predefined flow of heat to be dissipated from the sheet metal side that faces the respective coolant dispensing device, with a surface temperature of the respective sheet metal side being taken into account, the flatness of plate that is produced can be increased further with a simultaneously high throughput of the plate rolling train.

A straightening system and a straightening method are provided to perform straightening in conformity with the shape pattern of a material, the straightening system comprising: a cooling device configured to spray a cooling fluid in a predetermined pattern with respect to a plurality of regions of a material, divided in a width direction, to cool the material that is heated in a heating furnace and then passes through a rolling mill; a straightening device configured to straighten the material passed through the cooling device; a flatness measuring system configured to measure flatness of the material passed through the cooling device; and a controller configured to receive data of the flatness of the material from the flatness measuring system and to control the cooling device in response to the data to enhance the flatness of the material.

A closed loop roller leveler assembly for measuring flatness of a strip, having a roller leveler, a flatness sensor, and at least one arm operatively connected to the flatness sensor to raise and lower the flatness sensor. The flatness sensor has a plurality of sensor rolls, at least one load cell, and at least one laser sensor which is mounted on a positioner which oscillates the laser sensors across a width of the strip.

A closed loop roller leveler system has a roller leveler; a flatness sensor; and at least one arm for raising and lowering the flatness sensor. The sensor includes a plurality of sensing rollers extending across a width of a strip of material. The sensor further has at least one load cell and at least one laser sensor for measuring the flatness level of the strip.

A closed loop roller leveler system has a roller leveler; a flatness sensor; and at least one arm for raising and lowering the flatness sensor. The sensor includes a plurality of sensing rollers extending across a width of a strip of material. The sensor further has at least one load cell and at least one laser sensor for measuring the flatness level of the strip.

A method for improving the flatness of a rolled sheet or strip includes the application of differential cooling. A cooling agent can be selectively applied along the width of the strip. More cooling can be applied to the edges of the strip, where tension is greatest, to increase tension at the edges. The strip can be allowed to lengthen at these edges, which can improve flatness. In some embodiments, a closed loop flatness control system is used to measure the flatness of a strip and automatically adjust the differential cooling based on the measurement.

A method for improving the flatness of a rolled sheet or strip includes the application of differential cooling. A cooling agent can be selectively applied along the width of the strip. More cooling can be applied to the edges of the strip, where tension is greatest, to increase tension at the edges. The strip can be allowed to lengthen at these edges, which can improve flatness. In some embodiments, a closed loop flatness control system is used to measure the flatness of a strip and automatically adjust the differential cooling based on the measurement.

A method and device for measuring the flatness of a metal product traveling on a path. The product has at least plastic or elastoplastic deformation properties. The metal product (1) is in the form of a strip that travels (D) under tension over a flatness measurement assembly (2) that deflects the product, such as at least one measuring roller (RM) that deflects the product. Measure flatness by measuring the longitudinal tension over a deflection zone. Perform the flatness measurement by: a first longitudinal tension measurement value (T1) by the measuring roller, determining a model of stress over the thickness of the strip as a function of conditions of plastic or elastoplastic deformation of the product, calculating a correction factor for the longitudinal deformation according to the determined stress model, calculating a corrective value (T1, T2) for the first longitudinal tension measurement value (T1) at at least one evaluation point (M1, M2) as a function of the longitudinal deformation correction factor (Z1), calculating a corrected flatness measurement value (PC) at at least one of the evaluation points.

A method and device for measuring the flatness of a metal product traveling on a path. The product has at least plastic or elastoplastic deformation properties. The metal product (1) is in the form of a strip that travels (D) under tension over a flatness measurement assembly (2) that deflects the product, such as at least one measuring roller (RM) that deflects the product. Measure flatness by measuring the longitudinal tension over a deflection zone. Perform the flatness measurement by: a first longitudinal tension measurement value (T1) by the measuring roller, determining a model of stress over the thickness of the strip as a function of conditions of plastic or elastoplastic deformation of the product, calculating a correction factor for the longitudinal deformation according to the determined stress model, calculating a corrective value (T1, T2) for the first longitudinal tension measurement value (T1) at at least one evaluation point (M1, M2) as a function of the longitudinal deformation correction factor (Z1), calculating a corrected flatness measurement value (PC) at at least one of the evaluation points.