C21D11/005

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.

Material structure prediction apparatus, product manufacturing method and material structure prediction method

The material structure prediction apparatus includes a temperature calculator calculating temperatures at calculation points, based on a temperature condition, a nucleation count calculator calculating a nucleation count in the calculation target region, a precipitated phase generation point determining module determining, from the calculation points, a precipitated phase generation point, a grain growth calculator calculating a grain growth of the precipitated phase at the precipitated phase generation point, and a material structure prediction module predicting the structure of the material, based on the grain growth of the precipitated phase.

METHOD AND APPARATUS FOR COOLING A TOOL

The invention relates to a method for cooling a tool in a heat treatment furnace, wherein: the tool is supplied during normal cooling operation with coolant from a coolant reservoir through a supply inlet (1), which coolant is returned into the coolant reservoir from the tool via a return flow (2); the supply inlet (1) is coupled by means of an electric actuator (3) alternatively to the coolant reservoir or to the public water supply and the return flow (2) is coupled by means of a further electric actuator (3) alternatively to the coolant reservoir or to the public waste water system (4); the actuators (3, 3′) are supplied with a feed current during normal cooling operation and held in a first position in which coolant is supplied to the tool through the supply inlet (5) from the coolant reservoir and the coolant is fed back through the return flow (2, 6) into the coolant reservoir; and, upon interruption in the power supply, the actuators (3, 3′) are forced into an emergency position in which cold water is supplied to the tool through the supply inlet (7) from the public water supply and the water is discharged through the return flow (2, 8) into the public waste water system (4).

METHOD OF PRESS-HARDENING A HOT-SHAPABLE PLATE
20210395848 · 2021-12-23 ·

A hot-shapable uncoated steel-plate workpiece is press hardened by first transporting the plate through a heating zone continuously or discontinuously and there heating the plate to an austenitizing temperature while blocking entry of oxygen into the heating zone. Then the heated plate is cooled in a cooling zone to a martensitizing temperature below the austenitizing temperature without contacting the heated plate with oxygen. Finally, immediately and without cooling of the cooled workpiece to a martensite start temperature, the cooled workpiece is deformed at least partially in a finishing press into a desired shape.

Method for manufacturing bainite high-strength seamless steel tube, and bainite high-strength seamless steel tube

A method for manufacturing a bainite high-strength seamless steel tube, comprising the following steps: smelting, manufacturing a billet, heating, perforating, rolling, stretch reducing or sizing to obtain tube, and cooling. In the cooling step, the quenching starting temperature is controlled to be at least 20° C. higher than the Ar3 temperature of the steel grade; the finish cooling temperature is controlled to be within a range between T1 and T2, where T1=519-423 C-30.4Mn, T2=780-270 C-90Mn, and the units of the T1 and the T2 are ° C.; in the formulas, C and Mn respectively represent the mass percents of element C and element Mn of the steel grade, the content of the element C is 0.06-0.2%, and the content of the element Mn is 1-2.5%; the cooling rate is controlled to be 15-80° C./s; and the finished product of the bainite high-strength seamless steel tube is directly obtained after the cooling step. The manufacturing of a bainite high-strength seamless steel tube using the method requires neither the addition of precious alloying elements nor the subsequent heat treatment. Therefore the production costs are low.

Methods for die trimming hot stamped parts and parts formed therefrom

A method of forming a hot stamped, die quenched, and die trimmed part is provided. The method includes hot stamping and die quenching a blank with a quench die and forming a die quenched panel. The quench die includes at least one slow-cooling channel. The die quenched panel is die trimmed along the at least one localized soft zone that is adjacent a hard zone. The blank may be formed from a press hardenable steel (PHS), and the at least one soft zone may have a ferritic microstructure and the at least one hard zone may have a martensitic microstructure. The at least one localized soft zone may have a microhardness between about 200 HV and about 250 HV and the hard zone may have a microhardness between about 400 HV and about 500 HV.

Systems and methods for quenching a metal strip after rolling

Systems and methods of quenching a metal substrate include cooling a top surface and a bottom surface of the metal substrate until a strip temperature is cooled to an intermediate temperature. Cooling of the top surface of the metal substrate is discontinued when the strip temperature reaches the intermediate temperature, and cooling of the bottom surface of the metal substrate continues until the metal substrate reaches a target temperature, where the target temperature is less than the intermediate temperature.

Wear-resistant steel having excellent hardness and impact toughness, and method for producing same
11371125 · 2022-06-28 · ·

A wear-resistant steel having excellent hardness and impact toughness and a method for producing same can include: 0.29-0.37 wt % of carbon, 0.1-0.7 wt % of silicon, 0.6-1.6 wt % of manganese, 0.05 wt % or less of phosphorus, 0.02 wt % or less of sulfur, 0.07 wt % or less of aluminum, 0.1-1.5 wt % of chromium, 0.01-0.8 wt % of molybdenum, 0.01-0.08 wt % of vanadium, 50 ppm or less of boron, and 0.02 wt % or less of cobalt; and optionally one or more of 0.5 wt % or less of nickel, 0.5 wt % or less of copper, 0.02 wt % or less of titanium, 0.05 wt % or less of niobium, and 2-100 ppm of calcium; with the remainder of Fe and other inevitable impurities.

Section and method for cooling a continuous line combining dry cooling and wet cooling

Cooling section for a steel strip continuous annealing or galvanizing line arranged to handle a metal strip (1), said section comprising at least one area (2) for dry cooling set up to project gas on said steel strip and at least one wet cooling area (5) set up to project a liquid or a mixture of gas and liquid on said steel strip.

ENDLESS HOT-ROLLED STRIP PRODUCTION DEVICE AND METHOD FOR FERRITE ROLLING

The device has a short production line, and all components are reasonably configured. A multifunctional cooling control device is adopted to integrate high-pressure water descaling and intermediate billet cooling functions, which is simpler and more efficient. Layout of a 4R+(3−4)F rolling mill, four thermos-detectors and short-distance underground coilers are use. The method includes the steps: carrying out continuous casting to manufacture a slab, high-pressure water rotating descaling, rough rolling by a four-stand high reduction rough rolling unit, machining by a drum shear, cooling after high-pressure water descaling in the multifunctional cooling control device, finish rolling by a three-stand or four-stand finish rolling unit, air cooling, dividing coils by a high-speed flying shear, and coiling by underground coilers, wherein temperature monitoring is respectively carried out after rough rolling, before finish rolling, after finish rolling, and before coiling by the underground coiler.