An internal oxidation starting temperature, estimation device estimates an internal oxidation starting temperature which is a minimum temperature required for an internal oxide layer to grow on a surface of an easily oxidizable element-containing hot-rolled steel sheet including Si, Mn, or Al or any combination thereof. The internal oxidation starting temperature estimation device includes an internal, oxidation starting temperature estimation unit that estimates the internal oxidation starting temperature on the basis of concentrations of the Si, the Mn, and the Al included in the easily oxidizable element-containing hot-rolled steel sheet.

Systems and methods for reducing the thickness of a strip of an aluminum-based material are disclosed. The aluminum-based material is pre-heated before running the material through a warm rolling process. The systems include devices for pre-heating, which can include a heated payoff station or a dedicated pre-heating station that applies heated rolls or acts as a heated tunnel.

The device and method for manufacturing metal clad strip continuously provided by the present invention, combines casting, rolling and heat treatment used for the single material manufacture with the continuous and large-scale manufacture method for the clad strip, greatly improves the productivity of clad strip. The present invention can be used for manufacturing single-sided or double-sided clad strips with different thickness specifications, wherein the base layer material or the clad layer material can be selected in a wide range, including carbon steel, stainless steel, special alloy steel, titanium, copper and the like. In the present application, continuous casting and rolling clad strip is implemented, which decrease the energy consumption and costs.

Systems and methods for reducing the thickness of a strip of an aluminum-based material are disclosed. The aluminum-based material is pre-heated before running the material through a warm rolling process. The systems include devices for pre-heating, which can include a heated payoff station or a dedicated pre-heating station that applies heated rolls or acts as a heated tunnel.

A rolling process for long solid-section products includes the steps of rolling stock through a plurality of rolling mill stands, the rolled stock being subjected to a tensile load, between the plurality of stands, that generates a single-axial deformation greater than 0.1 in the rolling direction, and is also deformed by compression between the rolls of at least one of the rolling mill stands, thereby achieving a reduction in the cross section area of at least 5%, preferably of between 5 and 50%. A rolling mill, in which a plurality of stands is connected by spacer elements designed to offset the tensile load; a rolling mill, in which a plurality of stands is connected by elements designed to offset the overturning moment generated by the tensile load; and a rolling mill, in which the aforesaid rolling stands maintain a non-slip condition.

An apparatus line for manufacturing seamless steel pipes and tubes includes: a heating apparatus for heating a steel raw material; a piercing apparatus for piercing the heated steel raw material thus forming a hollow material; and a rolling apparatus for applying working to the hollow material to form a seamless steel pipe having a predetermined shape. A cooling apparatus is arranged on an exit side of the rolling apparatus. A heated steel raw material is worked by the rolling apparatus after being pierced by the piercing apparatus, and thereafter, using a surface temperature of a hollow piece before being cooled by the cooling apparatus as a cooling start temperature, the hollow piece is cooled to a cooling stop temperature differing by 50° C. or more from the cooling start temperature and being equal to or above 600° C. at an average cooling speed of 1.0° C./s or more in terms of an outer surface temperature.

A heat-insulating device for use in a processing line for a metal strip to be transported along a strip conveying direction, preferably for use in a rolling mill, wherein the heat-insulating device has: at least one heat-insulating carriage which has a heat-insulating hood which, in order to reduce temperature losses, can be moved over the metal strip; and a transport, which has a drive for moving the heat-insulating carriage and is configured in such a way that the heat-insulating carriage can be moved out of the processing line and into the latter horizontally, preferably along a straight line.

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 is 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.

There is provided a production method for on-line improving precipitation strengthening effect of Ti microalloyed hot-rolled high-strength steel, comprising: casting a molten steel with microalloying element Ti added to obtain an ingot; after heating the ingot, subjecting it to rough rolling, finish rolling, laminar cooling and coiling to obtain a hot-rolled coil; after unloading the coil, covering the coil on-line with an insulating enclosure and moving it into a steel coil warehouse along with a transport chain; after a specified period of on-line insulating time, removing the coil from the insulating enclosure, and cooling it to room temperature in air, wherein the microalloying element Ti has a content of ≥0.03 wt %; the coiling is performed at a temperature of 500-700° C.; said covering on-line with an insulating enclosure means each hot-rolled coil is individually covered with an independent, closed insulating enclosure unit within 60 minutes after unloading; the on-line insulating time is ≥60 minutes. The method of the present disclosure is characterized by low cost and high efficiency, and is not affected by surroundings.

A hot rolled steel sheet is provided, which is excellent in collision characteristics, excellent in anisotropy of toughness, and high in strength. The hot rolled steel sheet is characterized by containing, by mass %, C: 0.10% to 0.50%, Si: 0.10% to 3.00%, Mn: 0.5% to 3.0%, P: 0.100% or less, S: 0.010% or less, Al: 1.00% or less, N: 0.010% or less and a balance of Fe and impurities, wherein a metal structure at position of ¼ thickness from surface in L-cross-section of the steel sheet comprises prior austenite grains of average value of aspect ratios of 2.0 or less, average grain size of 0.1 μm to 3.0 μm, and coefficient of variation of a standard deviation of grain size distribution/average grain size of 0.40 or more, and a texture with X-ray diffraction intensity ratio of {001}<110>orientation for random samples of 2.0 or more, and the steel sheet has tensile strength of 1180 MPa or more.