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 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 rolling oil supply system is configured to supply rolling oil to a rolling stand selected from a plurality of rolling stands included in a tandem rolling mill, a first rolling oil supply system configured to circulate and supply rolling oil after removing wear powder generated by rolling, and a second rolling oil supply system configured to supply rolling oil containing the wear powder generated by rolling are provided. Mixed rolling oil in which the rolling oil supplied from the first rolling oil supply system and the rolling oil supplied from the second rolling oil supply system are mixed is supplied to selected fourth and fifth rolling stands.

A rolling mill exit side temperature control system includes the following features. A second valve control unit controls a valve opening of a second valve to cause a flow rate actual value detected by a flow rate detector to coincide with a flow rate target value. A remaining coolant discharging section controls a first valve to an open state and the second valve to a closed state by setting the flow rate target value to zero, before a material to be rolled reaches a rolling mill. A flow rate target value setting section sets the flow rate target value to a value corresponding to a target temperature of the material to be rolled on the entry side and the exit side of the rolling mill after the control by the remaining coolant discharging section.

A rolling mill exit side temperature control system includes the following features. A second valve control unit controls a valve opening of a second valve to cause a flow rate actual value detected by a flow rate detector to coincide with a flow rate target value. A remaining coolant discharging section controls a first valve to an open state and the second valve to a closed state by setting the flow rate target value to zero, before a material to be rolled reaches a rolling mill. A flow rate target value setting section sets the flow rate target value to a value corresponding to a target temperature of the material to be rolled on the entry side and the exit side of the rolling mill after the control by the remaining coolant discharging section.

This manufacturing method for a slab is a method for manufacturing a slab by a continuous casting equipment including a twin-drum type continuous casting apparatus, a cooling apparatus, an in-line mill, and a coiling apparatus. The method includes calculating a friction coefficient from measured values of a rolling load and a forward slip when the slab is rolled, by use of a rolling analysis model, and controlling a lubrication condition during rolling of the slab so that the friction coefficient falls within a predetermined range, wherein, when the friction coefficient is calculated from the measured values of the rolling load and the forward slip by use of an Orowan theory and a deformation resistance model formula based on a Shida's approximate formula as the rolling analysis model, the predetermined range is 0.15 or more and 0.25 or less.

Systems and methods for using full-width hot sprays to pre-heat rolling mills prior to processing of metal sheet or plate are described herein. The hot sprays may be individually controlled. Using hot sprays can allow the rolling mill to reach operating temperature and achieve a desired thermal crown so that metal sheet or plate may be processed immediately within tolerances for flatness and gauge accuracy. Pre-heating of rolling mills can eliminate the need of the rolling mill to operate in a transitional period of work roll heating and can increase efficiency by eliminating or reducing scrap material and mill downtime. Hot sprays may also be incorporated with existing coolant systems to provide thermal control systems for rolling mills with bi-directional temperature controls.

Systems and methods for using full-width hot sprays to pre-heat rolling mills prior to processing of metal sheet or plate are described herein. The hot sprays may be individually controlled. Using hot sprays can allow the rolling mill to reach operating temperature and achieve a desired thermal crown so that metal sheet or plate may be processed immediately within tolerances for flatness and gauge accuracy. Pre-heating of rolling mills can eliminate the need of the rolling mill to operate in a transitional period of work roll heating and can increase efficiency by eliminating or reducing scrap material and mill downtime. Hot sprays may also be incorporated with existing coolant systems to provide thermal control systems for rolling mills with bi-directional temperature controls.

A method and a device for controlling a parameter, for example the profile or the flatness, of a rolled stock in strip form. A cooling jacket that can be brought up to the roll and is designed to be variable in its effective length b in the circumferential direction of the roll is used as a final controlling element.

A method and a device for controlling a parameter, for example the profile or the flatness, of a rolled stock in strip form. A cooling jacket that can be brought up to the roll and is designed to be variable in its effective length b in the circumferential direction of the roll is used as a final controlling element.