Nippon Steel Corporation

Nippon Steel Sumitomo Metal Corporation

Aisin Aw Industries Co., Ltd.

Aisin Fukui Corporation

Hiroshi Fukuchi

Hiroyuki Mitake

Naruhiko Nomura

Yasushi Kurisu

Kazuto Yamamura

Norimasa Yamasaki

Yoshiaki Shia

Tetsuo Shima

Yuuichi Ishimori

Yuichi Ishimori

Satoshi Hirose

Kazuo Hikida

Atsushi Seto

Ken Takata

Akihiro Seki

Nobuyuki Naito

Yoichi Jinza

Tsutomu Haeno

Hiroo Ishibashi

Kenji Saita

Shizuo Kohinata

Kiyoshi Uda

Yasunobu Tsutsumi

A cooling method for a workpiece includes placing entirety of the workpiece in an inner space of a recess provided on a molding surface of a lower mold, pressing or restraining the workpiece by a mold including the lower mold and an upper mold in which a protrusion corresponding to the recess of the lower mold is provided on a molding surface, supplying a liquid coolant to the inner space of the recess through a coolant supply passage provided in at least one of the lower mold and the upper mold by a pump, and discharging air in the inner space of the recess upward through an air escape passage, and cooling the workpiece by immersing the entirety of the workpiece, which has been heated, in the liquid coolant that fills the recess.

Cooling method for workpiece

A structural memberincludes a hat memberand a closing plate. The length LY of the tubular portion formed by the hat memberand the closing plateis 6 or more times the height H of a pair of side wallsand. Each of the side wallsandincludes a high-strength portionA orA and low-strength portionsB orB. The high-strength portion has a yield strength not less than 500 MPa. The low-strength portions have a yield strength of 60 to 85% of that of the high-strength portion. Each high-strength portion extends a distance not less than (&#x2154;)H and not more than 3H as measured in the direction in which the ridges extend, and is provided such that the high-strength portions of the pair of side walls face each other. A pair of low-strength portions sandwich the associated high-strength portion.

Structural member and structural member for vehicle

In a mold, at least one of a lower mold and an upper mold includes a coolant supply passage through which a liquid coolant is supplied to an inner space of a recess, and the mold includes an air escape passage through which air in the inner space of the recess is discharged upward.

Mold, mold apparatus, and cooling method for workpiece

A structural member () includes: a hat member (); and a closing plate (). The hat member () includes: a top-surface portion (); a pair of side walls () extending from both edges of the top-surface portion (); and flanges (). The closing plate () is in contact with the flanges (). Each of the side walls () includes a low-strength portion () extending from one edge of the side wall () to a position at a distance Sh. The distance Sh is 20 to 40% of the height H of the side wall (). The yield strength of the low-strength portion () is 60 to 85% of the yield strength of the side wall () as measured at a position (mid) of one-half of the height of the side wall ().

Structural member and vehicle

A metal pipe includes a pair of side walls facing each other and having a height H, a top portion connected to an upper edge of each of the pair of side walls, and a bottom portion connected to a lower edge of each of the pair of side walls. The metal pipe has a length six times the height H of the side walls or more. Each side wall pair includes a high-strength portion and a pair of low-strength portions, the low strength portions sandwiching the high strength portion. A high-strength portion dimension is not less than &#x2154;H and not more than 3H as measured longitudinally of the metal pipe, the high-strength portions forming opposite portions of the side wall pairs. The low-strength portion yield strength is 60 to 85% of that of the high-strength portion, whose yield strength is not less than 500 MPa.

Metal pipe and structural member using metal pipe for vehicle

A steel sheet heating method that heats a steel sheet (K) to be pressed before hot press molding includes: bringing the steel sheet into a heating furnace () including a heater () on an inside surface of the heating furnace in a state where the steel sheet is supported in a vertical direction while an unnecessary portion of the steel sheet that becomes unnecessary after molding is fixedly supported by a support member (); and performing heating at a prescribed temperature in the heating furnace, then taking the steel sheet out of the heating furnace, and after that cutting and removing the unnecessary portion before hot press molding or during hot press molding.

Steel sheet heating method and steel sheet heating apparatus

In hot press forming a thin steel sheet K, when cooling the thin steel sheet K by supplying a refrigerant to an ejection hole () communicated from a supply path () inside a lower mold (), precooling in which an ejection amount per unit time period of the refrigerant from the ejection hole () is suppressed is carried out, and thereafter, main cooling is carried out by increasing the ejection amount per unit time period.

Cooling method for hot press forming and hot press forming apparatus

This welding method is a flash butt welding method of a pair of track rail steel pieces, having: a preheating process in which electric current is made to flow for a predetermined time in a state in which the welding surfaces of a pair of track rail steel pieces are forcibly brought into contact with each other, and vicinities of the welding surfaces are heated by resistance heating; a former flashing process in which flashing is partially caused in the welding surfaces, and the welding surfaces are heated by the resistance heating and arc heating of the flashing; and a latter flashing process in which the flashing is furthermore caused throughout the entire welding surfaces, and the entire welding surfaces are uniformly heated by the resistance heating and arc heating of the flashing, in which a latter flashing velocity is 2.1 mm/sec to 2.8 mm/sec in the latter flashing process.

Flash butt welding method of rail steel

The present invention provides a hot press molding method for molding a heated metallic plate (K) using a molding die () comprising an upper die () and a lower die (). According to the method, the heated metallic plate is arranged between the upper die and the lower die, the upper die and the lower die are brought together, and the metallic plate held between the dies is pressed. After the metallic plate is pressed, a refrigerant in the form of a liquid or mist is supplied via a plurality of supply holes provided to the lower die to a surface of the metallic plate held between the dies, and once the refrigerant has finished being supplied, a gas is sprayed onto the surface of the metallic plate via the plurality of supply holes. It is thereby possible to remove, with maximum speed, liquid refrigerant adhering to the metallic plate when the supply of liquid refrigerant is stopped.

Hot press molding method and hot press molding die

A metal plate material hot molding apparatus is provided for press molding a heated metal plate material. The apparatus may include supply piping for a cooling medium in a mold, and ejection holes penetrating from a molding surface of the mold to the supply piping. The exemplary apparatus may also include discharge piping for the cooling medium situated in the mold, and discharge holes penetrating from the molding surface of the mold to the discharge piping, and cooling piping. Molding procedure can be performed while the cooling medium is ejected from the ejection holes to a gap between the metal plate material and the mold.

Metal plate material hot press molding apparatus and hot press molding method

Apparatus for hot press-forming metal plate material

This invention provides a bending roll apparatus capable of preventing barrel-like deformation of a pipe occurring during a roll bending work and of manufacturing a small diameter elongated pipe. In an apparatus for manufacturing a pipe by pushing rolls to a core roll, feeding a metal sheet to their contact portions and performing a bending work, the bending roll apparatus comprises a core roll formed of a metal and a plurality of push rolls having a surface portion thereof formed of an elastic material and disposed around the core roll. The invention further provides, in a bending roll apparatus, a core roll formed of a metal, a plurality of push rolls formed of a metal and disposed around the core roll, and holding the core roll when a metal sheet is bent, and a guide belt formed of an elastic material, interposed between the core roll and each of the push rolls, contacting on a core roll surface on a side opposite to an entry side of the metal sheet and driven in synchronism with the core roll.

Growing community of inventors

Tokyo, Japan

Hiroshi Fukuchi