C21D11/00

Method for operating a continuous annealing line for the processing of a rolled good

A method operates a continuous annealing line for the processing of a rolled good, in particular a metal strip. A property of the rolled good in relation to a point or a section of the rolled good is fed to a computer-aided model as an input variable. The point or the section of the rolled good is located before or in the continuous annealing line. For the purpose of precise control of the continuous annealing process, at least one material property of the rolled good after the continuous annealing process is simulated by the computer-aided model and compared with a specified target value. If the simulated material property deviates from the target value, at least one process variable of the continuous annealing process is controlled as long as the point or the section of the rolled good is located before or in the continuous annealing line.

Method and apparatus for controlling a furnace pressure of a continuous annealing furnace

A method for controlling furnace pressure of a continuous annealing furnace is disclosed. The method comprises detecting a coal gas flow volume and an air flow volume in each section by use of a coal gas flow volume detector and an air flow volume detector disposed in each section of a continuous annealing furnace, respectively, adding up the coal gas flow volume detected in each section to obtain a total input coal gas flow volume; adding up the air flow volume detected in each section to obtain a total input air flow volume, and calculating a pre-combustion gas pressure in the furnace based on the total input coal gas flow volume and the total input air flow volume; detecting compositions of the coal gas and a ratio of the coal gas to the air by use of a composition detector; detecting a pre-combustion gas temperature in the furnace by use of a thermocouple; predicting post-combustion gas compositions and a total gas volume based on chemical combustion reaction equations and based on the total input coal gas flow volume, the total input air flow volume, the coal gas compositions and the ratio of the coal gas to the air; igniting the coal gas and the air in the furnace; and detecting a post-combustion gas temperature in the furnace by use of a thermocouple; calculating a post-combustion gas pressure in the furnace based on the pre-combustion gas pressure in the furnace, pre-combustion gas temperature in the furnace and the post-combustion gas temperature in the furnace; and calculating an opening degree for an exhaust gas fan based on the pre-combustion gas pressure in the furnace and the post-combustion gas pressure in the furnace and by use of a gas increment pass algorithm, and using the opening degree to control the exhaust gas fan.

Method and apparatus for controlling a furnace pressure of a continuous annealing furnace

A method for controlling furnace pressure of a continuous annealing furnace is disclosed. The method comprises detecting a coal gas flow volume and an air flow volume in each section by use of a coal gas flow volume detector and an air flow volume detector disposed in each section of a continuous annealing furnace, respectively, adding up the coal gas flow volume detected in each section to obtain a total input coal gas flow volume; adding up the air flow volume detected in each section to obtain a total input air flow volume, and calculating a pre-combustion gas pressure in the furnace based on the total input coal gas flow volume and the total input air flow volume; detecting compositions of the coal gas and a ratio of the coal gas to the air by use of a composition detector; detecting a pre-combustion gas temperature in the furnace by use of a thermocouple; predicting post-combustion gas compositions and a total gas volume based on chemical combustion reaction equations and based on the total input coal gas flow volume, the total input air flow volume, the coal gas compositions and the ratio of the coal gas to the air; igniting the coal gas and the air in the furnace; and detecting a post-combustion gas temperature in the furnace by use of a thermocouple; calculating a post-combustion gas pressure in the furnace based on the pre-combustion gas pressure in the furnace, pre-combustion gas temperature in the furnace and the post-combustion gas temperature in the furnace; and calculating an opening degree for an exhaust gas fan based on the pre-combustion gas pressure in the furnace and the post-combustion gas pressure in the furnace and by use of a gas increment pass algorithm, and using the opening degree to control the exhaust gas fan.

Modular micro mill and method of manufacturing a steel long product
09725780 · 2017-08-08 · ·

A modular micro mill for manufacturing steel long product from scrap metal using an induction melting furnace is disclosed. Scrap or pre-refined metal is delivered and melted in the induction melting furnace, the melted steel then being transferred by a preheated tundish to a casting station for producing billets. From the caster the billets are transferred directly to a billet staging station and stored in queue for delivering to main conveyor leading directly to the rolling mill without being cooled to ambient. The bars produced by the rolling mill are then quenched to impart desired metallurgical properties within the finished product. A control system runs the operation of the production line of the modular micro mill, the control system specifically adapting production rates, conveyor speeds, temperatures, etc. of components upstream within the production line based on the specific requirements and/or dimensions of the finished product exiting the production line.

Modular micro mill and method of manufacturing a steel long product
09725780 · 2017-08-08 · ·

A modular micro mill for manufacturing steel long product from scrap metal using an induction melting furnace is disclosed. Scrap or pre-refined metal is delivered and melted in the induction melting furnace, the melted steel then being transferred by a preheated tundish to a casting station for producing billets. From the caster the billets are transferred directly to a billet staging station and stored in queue for delivering to main conveyor leading directly to the rolling mill without being cooled to ambient. The bars produced by the rolling mill are then quenched to impart desired metallurgical properties within the finished product. A control system runs the operation of the production line of the modular micro mill, the control system specifically adapting production rates, conveyor speeds, temperatures, etc. of components upstream within the production line based on the specific requirements and/or dimensions of the finished product exiting the production line.

Device and method for detecting heating treatment temperatures of double steel wires

Disclosed are a device and method for detecting heating treatment temperatures of double steel wires. The temperature detection device includes a double wires coiling machine, two heating mechanisms for respectively heating two steel wires, and two temperature detection mechanisms for respectively detecting temperatures of the two steel wires in real time, and a controller electrically connected to the two heating mechanisms and the double-wire spring coiling machine respectively.

Device and method for detecting heating treatment temperatures of double steel wires

Disclosed are a device and method for detecting heating treatment temperatures of double steel wires. The temperature detection device includes a double wires coiling machine, two heating mechanisms for respectively heating two steel wires, and two temperature detection mechanisms for respectively detecting temperatures of the two steel wires in real time, and a controller electrically connected to the two heating mechanisms and the double-wire spring coiling machine respectively.

Cooling device and production method for rail

There are provided an apparatus for cooling a rail and a method for manufacturing a rail, capable of inexpensively manufacturing a rail with high hardness and high toughness. The apparatus for cooling a rail, configured to jet a cooling medium to the head portion and foot portion of a rail in an austenite temperature range to forcibly cool the rail, includes: a first cooling unit including plural first cooling headers configured to jet the cooling medium as gas to the head top face and head side of the head portion, and first driving units configured to move at least one first cooling header of the plural first cooling headers to change the jet distance of the cooling medium jetted from the first cooling header; and a second cooling unit including a second cooling header configured to jet the cooling medium as gas to the foot portion.

Method for and equipment for suppressing discoloration of Al—Mg products

Method and means for suppressing discoloration during thermal treatment of a product of a magnesium containing aluminium alloy, the alloy contains in wt. % Mg: 0.45-12.0, with a preferred range of 0.45-6.0 wt %. The product, being either an extrusion billet, a sheet ingot, a cast product, or a forged product is heated to a temperature T where it is prone to surface discoloration and oxidation, wherein during the thermal treatment it is exposed to a suppressing atmosphere comprising 0.5-5.0% CO.sub.2 gas with a preference for 0.5-1.5% CO.sub.2 gas.

High strength steel sheet and method of manufacturing the same

A high strength steel sheet is formed of steel having the composition containing by mass % over 0.015% and less than 0.100% C, less than 0.50% Si, over 1.0% and less than 2.0% Mn, 0.05% or less P, 0.03% or less S, 0.01% or more and 0.3% or less sol. Al, 0.005% or less N, less than 0.35% Cr, 0.0010% or more and 0.0050% or less B, less than 0.15% Mo, less than 0.030% Ti, and iron and unavoidable impurities as a balance, wherein the steel satisfies 2.1≤[Mneq]≤3.1, the microstructure of the steel includes a ferrite and a second phase, a volume fraction of the second phase is set to 2.0 to 12.0%, a total ratio of a volume fraction of martensite and a volume fraction of retained γ to the volume fraction of second phase is 60% or more, and the number of carbides which are present within ferrite particles, have an aspect ratio of 3.0 or less and have a diameter of 0.25 to 0.90 μm is set to 10000 pieces/mm.sup.2 or less.