In a method of producing a grain-oriented electrical steel sheet by hot rolling a steel slab having a chemical composition comprising C: 0.001 to 0.10 mass %, Si: 1.0 to 5.0 mass %, Mn: 0.01 to 0.5 mass %, S and/or Se: 0.005 to 0.040 mass %, sol. Al: 0.003˜0.050 mass % and N: 0.0010 to 0.020 mass %, subjecting to single cold rolling or two or more cold rollings including an intermediate annealing therebetween to a final thickness, performing primary recrystallization annealing, and thereafter applying an annealing separator to perform final annealing, a temperature range of 550° C. to 700° C. in a heating process of the primary recrystallization annealing is rapidly heated at an average heating rate of 40 to 200° C./s, while any temperature zone of from 250° C. to 550° C. is kept at a heating rate of not more than 10° C./s for 1 to 10 seconds, whereby the refining of secondary recrystallized grains is attained and grain-oriented electrical steel sheets are stably obtained with a low iron loss.

A manufacturing method provides a high-quality material for ring rolling. The manufacturing method of the material for ring rolling includes a step of heating a disk-shaped material for hot forging to a hot working temperature, a step of arranging the material for hot forging onto a lower die having a convex portion with a truncated conical shape, a step of forming a thin portion by pressing a center portion of the material for hot forging by using an upper die having a convex portion with a truncated conical shape, and a step of manufacturing a material for ring rolling by removing the thin portion wherein a center of gravity on a half section of the material for ring rolling is located so as to be closer to an outer peripheral surface of the half section than a center of the half section in a thickness direction of the half section.

A method for producing a flat steel product with high reflectivity, in which at least one surface has an arithmetic mean roughness Ra of less than 0.03 μm includes providing a flat steel product, at least one surface of which has an arithmetic mean roughness Ra of less than 2.5 μm. The flat steel product is cold rolled in a plurality of rolling passes. Also a flat steel product with high reflectivity in the finished re-rolled state on at least one of its surface has a low arithmetic mean roughness, a high gloss, and a high directed reflection. A solar concentrator is produced from such a flat steel product.

A heating device and a method for the inductive heating of a flat steel strip in a hot rolling mill. The heating device is between two rolling trains of the hot rolling mill and the flat steel strip runs at a speed through the heating device in a transporting direction. The heating device includes: transverse-field modules arranged one after the other along the transporting direction of the flat steel strip; longitudinal-field modules arranged one after the other along the transporting direction of the flat steel strip and arranged before or after the transverse-field modules along the transporting direction; a first power supply supplying at least one transverse-field module with a first alternating voltage; and a second power supply supplying at least one longitudinal-field module with a second alternating voltage. The power supplies have a converter and an electrically connected capacitor bank with multiple capacitors connected in parallel.

A first steel strip and a second steel strip (7) are rolled in succession in at least one roll stand (1) of a cold rolling mill. A rolling pause, in which no steel strip is rolled, is provided between the rolling of the first and the second steel strip (7). The first steel strip s fed over a first path starting from a first pay-off reel (2), and the second steel strip (7) is fed over a second path starting from the first pay-off reel (2), or from a second pay-off reel different from the first pay-off reel (2). The first steel strip is not heated as it is fed to the rolling mill (1), whereas, by contrast, the second steel strip (7) is heated. The second path is longer than the first path.

The invention relates to a method for producing a metallic strip or sheet (1), in which the strip or sheet (1) is rolled in a multi-stand rolling mill (11) and is discharged downstream of the last roll stand (14) of the rolling mill (11) in the conveying direction (F), wherein the strip or sheet (1) is cooled in the multi-stand rolling mill (11) and/or downstream of the rolling mill (11) as viewed in conveying direction (F), wherein a temperature of the strip or sheet (1) is measured upstream of the last roll stand (14) of the rolling mill (11) as viewed in conveying direction (F). Based on this measured temperature, a temperature for the strip or sheet (1) at the exit (A) of the last roll stand (14) of the rolling mill (11), is then determined purely by calculation with the aid of a temperature calculation model, with which temperature further processes of the manufacturing method can be controlled or regulated after a comparison with a predetermined reference value.

The present invention relates to the technical field of fabricating a metal composite strip, and specifically relates to a method for differential temperature rolling of composite strips based on actions of a friction roller and a device thereof. A method for differential temperature rolling of composite strips based on actions of a friction roller comprises steps of: S1: preparing a metal strip to be bonded, and performing surface treatment on the metal strip to be bonded; S2: frictionally heating the metal strip to be bonded by several sets of friction roller heating devices; measuring a surface temperature of the friction-heated metal strip to be bonded strip by a temperature detector; according to a measured temperature, adjusting a rotation speed of the friction roller in the friction roller heating devices; and S3: transporting the heated metal strip to be bonded to a rolling mill for rolling to obtain a metal composite strip. The invention adopts the friction roller heating devices in rolling process of the metal strip to be bonded, utilizes the friction heat generation effect of the high-speed rotating friction roller and the metal strip to be bonded, and generates different heat in the dissimilar metals by adjusting the speed of the friction roller, thereby generating different temperature rise to realize different temperature rolling of the metal composite strips.

A section mill (10) for the rolling of steel sections is disclosed. The section mill includes a universal mill stand (12) and an edger mill stand (14) for rolling a workpiece (18) in a plurality of back-and-forth passes into a steel section having a web and one or more flanges. The section mill further includes a cooling arrangement (16) for cooling the workpiece while it undergoes rolling during one or more of the passes. The cooling arrangement includes a cooling box (20) having a spray head (21) with spray openings (22) for spraying jets of pressurized cooling liquid against the workpiece. The cooling arrangement further includes an actuator (38, 34) configured to move the cooling box relative to the stand frame (58) of the universal mill stand and/or of the edger mill stand for adjusting a distance between the spray openings and the workpiece.

The invention relates to a thermal insulation device (1) for thermal insulation of a metal product in a rolling mill, comprising a support element (2), on which a number of thermal insulation elements (3) is arranged. To extend the service life of such a device, the invention makes provision that at least one thermal insulation device (3) is formed by multiple side parts (4, 5, 6, 7, 8, 9), which enclose within them an accommodating space for a thermal insulation material, wherein at least two of the side parts (4, 5, 6, 7, 8, 9) are connected with each other at their adjoining side areas by a hinge-like connection (10).

A method to improve the collapse resistance of metallic tubular products is disclosed. Stress is applied to the metallic tubular products in order to change the residual stress profile of the metallic tubular products, such as those that have completed a straightening process, resulting in a residual stress profile that improves collapse resistance. The metallic tubular product is subjected to radial compression processing to control the residual stress profile and to enhance collapse resistance. The radial compression process may be applied after the tubular product has been subjected to a straightening process.