Nippon Steel Corporation

Nippon Steel & Sumitomo Metal Corporation

Toru Yonebayashi

Koji Hashimoto

Koichi Sato

Yoshiaki Nakazawa

Ryuichi Nishimura

Kenichiro Otsuka

Masafumi Azuma

Daiki Kamada

Teruo Ito

Yasuhiro Ito

Toshiya Suzuki

Masaya Takahashi

Toshiki Nonaka

Satoshi Shirakami

Yasunori Sawa

Nobutaka Shimizu

Hitoshi Nikaido

Seiya Ishii

Yoshihiko Masuo

Ryuichi Harada

Yorifumi Sakamoto

A burring processing method including increasing a diameter of a prepared hole provided in a metal component and bending a part of the metal component to form a burring processed portion () including an upright portion () and a curved portion (), wherein in a cross-section that passes through an axis (cb) of the burring processed portion () and is parallel to the axis (cb) of the buffing processed portion (), a cross-sectional shape of the curved portion () on an inner surface of the curved portion consists of a curve, and a length of the curved portion () in a direction perpendicular to the axis (cb) of the burring processed portion () is at least 1.2 times a height of the curved portion in a direction parallel to the axis (cb) of the burring processed portion ().

Burring processing method, method for manufacturing burring processed product, burring processing mold, burring processing device, and burring processed product

A stiffened panel structure includes a panel-shaped component and a wire. The panel-shaped component has a panel body that curves in such a manner as to be convex outward. The wire has a first end portion and a second end portion. The first end portion is bonded to a first point on the inner surface of the panel body. The second end portion is bonded to a second point on the inner surface of the panel body. The wire is strained between the first point and the second point.

Stiffened panel structure

This steel sheet for a can is a steel sheet for a can containing, by mass %, C: 0.010% to 0.050%, Si: 0.020% or less, Mn: 0.10% to 0.60%, P: 0.020% or less, S: 0.020% or less, Al: 0.050% or less, N: 0.0100% or less, Nb: 0% to 0.03%, Ti: 0% to 0.03%, B: 0% to 0.0020%, and a remainder including Fe and unavoidable impurities, in which, when the number of carbides having an equivalent circle diameter of 2 μm or more and 5 μm or less is indicated by a, and the number of carbides having an equivalent circle diameter of 0.1 μm or more and less than 2 μm is indicated by b, a/b satisfies a range of the following formula (1), a fracture strain is 1.6 or more, and a sheet thickness is 0.10 to 0.30 mm<0.12  . . . (1).

Steel sheet for can and manufacturing method thereof

A method for producing a metal sheet with raised lines uses a rolling mill including roll stands. In a preparing step, a grooved roll is prepared, the grooved roll including grooves. In a choosing step, a stand at least one stage before the last stand is chosen. In an incorporating step, the grooved roll is incorporated in as an upper roll of the chosen, specified stand. In a forming step, a workpiece is formed into a metal sheet with raised lines formed corresponding to the respective grooves. In the forming step, a maximum rolling reduction achieved by rolls of the specified stand is set to a provisional value that is lower than a required value. After the leading edge of the workpiece reaches the stand next to the specified stand, the maximum rolling reduction of the specified stand is changed to the required value.

Method for producing metal sheet with raised lines, metal sheet with raised lines, and structural component

A producing method of the press formed product includes a preparation step of preparing a metal sheet as a starting material; and a press working step of performing press working on the starting material. The press working step includes: during a time period from when pushing-in of the starting material into the die by the punch is started or immediately thereafter until the pushing-in of the punch with respect to the die reaches a predetermined distance short of a bottom dead point for the pushing-in, holding the pad at a position distant from the punch by the predetermined distance; when the pushing-in of the punch with respect to the die reaches the predetermined distance short of the bottom dead point, receiving the pad in the die; and continuing the pushing-in of the punch with respect to the die and the pad to the bottom dead point.

Producing method, producing apparatus and producing equipment line of press formed product

A press-forming apparatus is an apparatus for producing a press-formed product having a hat-shaped cross section that has an external shape that curves in an L shape along a longitudinal direction in a planar view, and includes a punch, a first blank holder, a second blank holder, a preceding portion, a second die and a pad. When pushing the punch into a die to form a metal plate into the press-formed product, a first guide face of the preceding portion precedes a second guide face of the second die, and thereafter sliding of the first blank holder and the preceding portion relative to the punch is restricted and pushing of the punch into the die is continued in the restricted state to form the press-formed product. By this means, the press-formed product in which cracks and wrinkles are reduced is obtained.

Press-forming apparatus, method for producing press-formed product using the forming apparatus, and press-formed product

To provide a panel whose surface rigidity can be improved appropriately in accordance with a load. Provided is a panel including: a load point to which a load is applied from the outside; and a protrusion that protrudes from a surface of the panel and is formed continuously or discontinuously around the load point. The protrusion intersects, at a plurality of positions, each of a plurality of virtual straight lines extending radially from the load point.

Panel

There is provided a manufacturing apparatus and a manufacturing method for a stretch-formed product which can improve the yield of material in the stretch forming performed while clamping the blank by the lock beads. The manufacturing apparatus for a stretch-formed product includes a die and a blank holder which have clamping surfaces facing each other, a punch that, in a state where a margin of a blank of a sheet material is clamped by the clamping surfaces of the die and the blank holder, relatively presses a forming region of the blank into the die and thereby performs stretch forming on the forming region of the blank, and lock beads that are provided on the clamping surfaces of the die and the blank holder in mutually similar shapes and have first surfaces, second surfaces that intersect with the first surfaces, and third surfaces that intersect with the second surfaces from outer edges toward the centers of the die and the blank holder, the first surfaces each having a plurality of depression-protrusion parts.

Manufacturing apparatus and manufacturing method for stretch-formed product

A panel comprises a reinforcing unit including a plurality of first rectangular regions and a plurality of second rectangular regions. The first and second rectangular regions are in rows and columns, the first and second rectangular regions in each row being arranged alternately and the first and second rectangular regions in each column being arranged alternately. Each of the first rectangular regions includes a fully-covering first protrusion protruding in a first direction perpendicular to an imaginary reference plane and having a flat top surface. Each of the second rectangular regions includes a partially-covering second protrusion protruding in a second direction opposite to the first direction and having a flat top surface. A partially-covering reinforcing protrusion extends between opposite sides and protrudes in the first direction and having a flat top surface. The top surface of the reinforcing protrusion forms one face together with the top surface of the first protrusion.

Panel having recesses and protrusions

A front floor panel for an automotive body as a lightweight sheet can be reliably press-formed without a press forming loads becoming excessively large, can have desired stiffness, and noise and vibration characteristics for all directions since there is little stiffness anisotropy. The front floor panel includes a floor tunnel formed in a center in an automotive width direction to be oriented to a longitudinal direction, upright flanges disposed left and right formed at a left and right end portions in the automotive width direction to be joined to side sills, and a left and right plane portions formed between the upright flanges disposed left and right and a left and right longitudinal wall portions of the floor tunnel. In loop-shaped areas including outer edge portions of the plane portions, convex-concave parts in specific shapes are formed, and remaining areas excluding the loop-shaped areas are formed into flat sheet shapes.

Growing community of inventors

Tokai, Japan

Toru Yonebayashi