Abstract:
A cooling group for a laminar cooling device, including at least one cooling unit arranged above and below a strip to be cooled in order to supply the strip with a cooling liquid, including a central inlet via which cooling liquid is supplied, a distributing tube supplied with cooling liquid by the central inlet, and a number of supplying units supplied with cooling liquid from the distributing tube. Each supplying unit has a number of cooling nozzles via which cooling liquid is discharged onto the strip. In order to minimize the influence of the number of supplying units which are switched on or switched off, and thus have as little expenditure as possible, a volumetric flow rate regulating valve is arranged in or in front of the central inlet. The regulating valve is used to conduct a defined volume of cooling liquid through the central inlet per unit of time.
Abstract:
A method for controlling a cooling device which is set up to control temperature of a rolling stock such as a metal strip, which runs through a cooling device along a conveying direction of a rolling train. The cooling device is arranged upstream of the rolling train. The method includes determining total enthalpy of a system formed by the rolling stock; determining a measure for the formation of scale, which includes a scale factor that depends on chemical composition and surface temperature of the rolling stock, and a heat transfer coefficient of the scale; calculating a temperature distribution and/or average temperature in the rolling stock based on a temperature calculation model, in which the determined total enthalpy and the measure for the formation of scale are included; and setting a cooling capacity of the cooling device taking into account the calculated temperature distribution and/or average temperature in the rolling stock.
Abstract:
A method for producing a metal strip, in which the strip is rolled in a multi-stand rolling mill, is removed behind the final rolling stand of the rolling mill in the direction of conveyance, and is cooled in a cooling device. The strip or metal sheet is subjected to additional rapid cooling immediately after passing the working rollers of the final rolling stand, wherein the strip or the metal sheet is cooled at least partially within the extent of the final rolling stand in the direction of conveyance, wherein rapid cooling is performed by applying a coolant to the strip or metal sheet from above and from below, wherein the volume flow of coolant that is applied to the strip or metal sheet from below measures at least 120% of the volume flow of coolant that is applied to the strip or metal sheet from above.
Abstract:
A cooling device for cooling a metallic item and a method for operating the cooling device. Such cooling devices having a plurality of cooling bars arranged in parallel in groups for applying a coolant to the metallic item are known in the prior art. In order to be able to set a desired distribution function of the coolant over the width of the metallic item as precisely as possible, the cooling device provides that similar application regions in at least two cooling bars within a group are each formed differently with respect to their contour and/or with respect to their surface area.
Abstract:
In a method for controlling a metallurgical production plant by means of a microstructure model, which comprises a program which calculates at least one mechanical strength property of a product being produced, which program calculates the strength property on the basis of calculated metallurgical phase components of the microstructure of the produced product, wherein the metallurgical plant comprises a terminating cooling line, and wherein operating parameters for the metallurgical plant with adjustable output values, which are established at least partially in advance, are factored into the calculation of the mechanical strength property, the object of the method is to enable an advantageous adjustment of operating parameters in order to achieve desired mechanical strength properties in a product consisting of a metal steel and/or iron alloy. This object is achieved in that, as the operating parameters that are factored into the calculation of the strength property, the mass fraction of at least one alloy element that is present in the chemical composition of the metal steel and/or iron alloy being used, and at least one additional operating parameter, preferably a cooling rate which is set as part of a cooling process carried out after a rolling process, are detected, and an increase in the strength property in question of the produced product, said increase being achieved by modifying at least said additional operating parameter, is at least partially compensated for by reducing the mass fraction of one or more of the alloying elements of the metal steel and/or iron alloy being used.
Abstract:
A method for producing a metallic strip or sheet, in which the strip or sheet is rolled in a multi-stand rolling mill and is discharged downstream of the last roll stand of the rolling mill in a conveying direction. The strip or sheet is cooled in the multi-stand rolling mill and/or downstream of the rolling mill as viewed in the conveying direction, wherein a temperature of the strip or sheet is measured upstream of the last roll stand of the rolling mill as viewed in conveying direction. Based on this measured temperature, a temperature for the strip or sheet at the exit of the last roll stand of the rolling mill is then determined by calculation with the aid of a temperature calculation model, with which further temperature processes of the manufacturing method can be controlled or regulated after a comparison with a predetermined reference value.
Abstract:
A method for setting different cooling rates of metal strips or metal plates (rolling material) over the strip width of a cooling stretch in a hot-strip mill or heavy-plate mill is presented. According to the method, for the calculation of the cooling rate, the initial enthalpy distribution over the material width of the rolling material before the cooling is determined. Proceeding therefrom, a target enthalpy distribution is determined in the width direction and length direction of the rolling material while taking into account a calculation of the flatness and the mechanical properties by means of a microstructure model. Subsequently, the coolant amount and the coolant curve of the cooling stretch are set.