Method for reducing unevenness in a strip subjected to cooling by spraying of liquid, or a mixture of gas and liquid, along a cooling zone of a continuous heat treatment one, the cooling intensity being adjusted in the direction of travel of the strip so as to achieve a relative position between the Leidenfrost temperature and at least one temperature at which the metallurgical structure changes such that said cooling intensity minimizes the internal stresses of the strip, and device for implementing the method.

A cooling bar (1) for cooling rolled material (5) being moved in a transport direction (3) and in particular for reducing temperature differences in the temperature of the rolled material (5) transversely to the direction of transport (3). The cooling bar (1) has several full jet nozzles (11) by means of which a coolant beam of a coolant with an approximately constant jet diameter can be distributed to the rolling stock (5) in the direction of distribution (15). A cooling device has at least two cooling bars (1) of that type. The cooling bars extend transversely to a transport direction, one behind the other. Each cooling bar has a respective different pattern of jet nozzles and selection of applicable pattern of jet nozzles in their respective bars selectively cools the rolled material transversely to the transport direction.

A method for rolling a product to be rolled (3), wherein the product (3) is fed through a rolling gap (11) between two working rollers (9, 10) of a roll stand (1) and a cooling lubricant is introduced into a contact zone (15, 16), in which a contact surface (17, 18) of the product to be rolled (3) lies against a working roller (9, 10), in order to lubricate the contact zone (15, 16). Furthermore, a lubrication demand of the contact zone (15, 16) is determined in accordance with at least one process parameter of the rolling process and an additional lubricant is applied to the contact surface (17, 18) of the product to be rolled (3) before the rolling gap (11) at a specified application distance (D) if a cooling lubricant amount (C) presently introduced into the contact zone (15, 16) does not cover the lubrication demand. The application distance (D) is sized such that adhesion of the additional lubricant to the contact surface (17, 18) is increased and the lubricating effect in the contact zone (15, 16) is improved in comparison with application immediately before the rolling gap (11). In addition, the lubricant amount (C) introduced into the contact zone (15, 16) is reduced if additional lubricant is applied to the contact surface (17, 18).

A method for rolling a product to be rolled (3), wherein the product (3) is fed through a rolling gap (11) between two working rollers (9, 10) of a roll stand (1) and a cooling lubricant is introduced into a contact zone (15, 16), in which a contact surface (17, 18) of the product to be rolled (3) lies against a working roller (9, 10), in order to lubricate the contact zone (15, 16). Furthermore, a lubrication demand of the contact zone (15, 16) is determined in accordance with at least one process parameter of the rolling process and an additional lubricant is applied to the contact surface (17, 18) of the product to be rolled (3) before the rolling gap (11) at a specified application distance (D) if a cooling lubricant amount (C) presently introduced into the contact zone (15, 16) does not cover the lubrication demand. The application distance (D) is sized such that adhesion of the additional lubricant to the contact surface (17, 18) is increased and the lubricating effect in the contact zone (15, 16) is improved in comparison with application immediately before the rolling gap (11). In addition, the lubricant amount (C) introduced into the contact zone (15, 16) is reduced if additional lubricant is applied to the contact surface (17, 18).

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 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 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.

The invention relates to a hot reversing mill equipped with one or more cooling systems consisting of bars of nozzles spraying an aluminum blank. It also relates to the hot rolling process associated with this hot reversing mill wherein the cooling system serves at least once making it possible to produce aluminum sheets advantageously. It also relates to the process for rolling an AA6xxx series aluminum alloy wherein a blank is cooled during the hot rolling and a sheet obtained with this process. The invention makes it possible to enhance the productivity of reversing mills by enhancing the metallurgical quality and/or the productivity of the other fabrication steps. The invention is particularly useful for providing superior quality 6xxx alloy sheets intended for the automotive industry.

The invention relates to a hot reversing mill equipped with one or more cooling systems consisting of bars of nozzles spraying an aluminum blank. It also relates to the hot rolling process associated with this hot reversing mill wherein the cooling system serves at least once making it possible to produce aluminum sheets advantageously. It also relates to the process for rolling an AA6xxx series aluminum alloy wherein a blank is cooled during the hot rolling and a sheet obtained with this process. The invention makes it possible to enhance the productivity of reversing mills by enhancing the metallurgical quality and/or the productivity of the other fabrication steps. The invention is particularly useful for providing superior quality 6xxx alloy sheets intended for the automotive industry.