Abstract: Tooling used in a punching process which uses a die and projecting punch to form a worked material of steel sheet into a predetermined outer shape, in which tooling for punching, a radius of curvature Rd of a die cutting edge is from 0.03 mm to 0.2 mm and an angle (?) formed by a tangent drawn from a punch cutting edge to a projection shoulder and a direction perpendicular to a direction of movement of the punch is from 12° to 72°, and a punching method and shaping method using the same, are provided. Further, when making the die cutting edge (shoulder R part) a two-stage R of radii of curvature R1 and R2 and making a slant of a line passing through the centers of R1 and R2 ?, by making 0.03 mm?R1?0.2 mm, 1?R2/R1?5, 0?R2(1?sin ?1)?0.3t, and 30°???90°, punching hole expandability can be improved.

Abstract: A hot rolled steel sheet includes, as a chemical composition, at least one selected from Ti, REM, and Ca, and includes, as a metallographic structure, a ferrite as a primary phase, at least one of a martensite and a residual austenite as a secondary phase, and plural inclusions, wherein a total length in the rolling direction of both inclusion-cluster whose length in the rolling direction is 30 ?m or more and independent-inclusion whose length in the rolling direction is 30 ?m or more is 0 mm to 0.25 mm per 1 mm2.

Abstract: The present invention provides a high-strength steel sheet including: C: 0.03 to 0.25 mass %, Si: 0.1 to 2.0 mass %, Mn: 0.5 to 3.0 mass %, P: not more than 0.05 mass %, T.O: not more than 0.0050 mass %, S: 0.0001 to 0.01 mass %, N: 0.0005 to 0.01 mass %, acid-soluble Al: more than 0.01 mass %, Ca: 0.0005 to 0.0050 mass %, and a total of at least one element of Ce, La, Nd, and Pr: 0.001 to 0.01 mass %, with a balance including iron and inevitable impurities, in which the steel sheet contains a chemical component on a basis of mass that satisfies 0.7<100×([Ce]+[La]+[Nd]+[Pr])/[acid-soluble Al]?70 and 0.

Abstract: Punching hole expandability of high strength thin-gauge steel sheet is improved for the purpose of application of high strength thin-gauge steel sheet to auto parts so as to lighten the weight of automobiles. Tooling used in a punching process which uses a die and projecting punch to form a worked material of steel sheet into a predetermined outer shape, in which tooling for punching, a radius of curvature Rd of a die cutting edge is from 0.03 mm to 0.2 mm and an angle (?) formed by a tangent drawn from a punch cutting edge to a projection shoulder and a direction perpendicular to a direction of movement of the punch is from 12° to 72°, and a punching method and shaping method using the same, are provided. Further, when making the die cutting edge (shoulder R part) a two-stage R of radii of curvature R1 and R2 and making a slant of a line passing through the centers of R1 and R2 ?, by making 0.03 mm?R1?0.2 mm, 1?R2/R1?5, 0?R2(1?sin ?1)?0.3t, and 30°???90°, punching hole expandability can be improved.

Abstract: On a cross section with a sheet width direction of a high-strength hot-rolled steel sheet set as a normal line, with regard to an inclusion having a major diameter of 3.0 ?m or more, a maximum of a major diameter/minor diameter ratio expressed by (a major diameter of the inclusion)/(a minor diameter of the inclusion) is 8.0 or less, and a sum total of a rolling direction length per 1 mm2 cross section of a predetermined inclusion group composed of plural inclusions each having a major diameter of 3.0 ?m or more and a predetermined extended inclusion having a length in a rolling direction of 30 ?m or more is 0.25 mm or less. The plural inclusions composing the predetermined inclusion group congregate in both the rolling direction and a direction perpendicular to the rolling direction 50 ?m or less apart from each other. The predetermined extended inclusion is spaced over 50 ?m apart from all the inclusions each having a major diameter of 3.

Abstract: A hot rolled steel sheet includes, as a chemical composition, at least one selected from Ti, REM, and Ca, and includes, as a metallographic structure, a ferrite as a primary phase, at least one of a martensite and a residual austenite as a secondary phase, and plural inclusions, wherein a total length in the rolling direction of both inclusion-cluster whose length in the rolling direction is 30 ?m or more and independent-inclusion whose length in the rolling direction is 30 ?m or more is 0 mm to 0.25 mm per 1 mm2.

Abstract: The present invention provides a high-strength steel sheet including: C: 0.03 to 0.25 mass %, Si: 0.1 to 2.0 mass %, Mn: 0.5 to 3.0 mass %, P: not more than 0.05 mass %, T.O: not more than 0.0050 mass %, S: 0.0001 to 0.01 mass %, N: 0.0005 to 0.01 mass %, acid-soluble Al: more than 0.01 mass %, Ca: 0.0005 to 0.0050 mass %, and a total of at least one element of Ce, La, Nd, and Pr: 0.001 to 0.01 mass %, with a balance including iron and inevitable impurities, in which the steel sheet contains a chemical component on a basis of mass that satisfies 0.7<100×([Ce]+[La]+[Nd]+[Pr])/[acid-soluble Al]?70 and 0.

Abstract: On a cross section with a sheet width direction of a high-strength hot-rolled steel sheet set as a normal line, with regard to an inclusion having a major diameter of 3.0 ?m or more, a maximum of a major diameter/minor diameter ratio expressed by (a major diameter of the inclusion)/(a minor diameter of the inclusion) is 8.0 or less, and a sum total of a rolling direction length per 1 mm2 cross section of a predetermined inclusion group composed of plural inclusions each having a major diameter of 3.0 ?m or more and a predetermined extended inclusion having a length in a rolling direction of 30 ?m or more is 0.25 mm or less. The plural inclusions composing the predetermined inclusion group congregate in both the rolling direction and a direction perpendicular to the rolling direction 50 ?m or less apart from each other. The predetermined extended inclusion is spaced over 50 ?m apart from all the inclusions each having a major diameter of 3.

Abstract: High-strength parts and a method for producing them can be provided, where such parts exhibit hydrogen embrittlement resistance and strength after high-temperature forming. For example, the atmosphere in a heating furnace can contain less than about 10% hydrogen and/or have a dew point of about 30° C. or less. The amount of hydrogen penetrating a steel sheet during heating can thereby be reduced. After forming, quench hardening in a die assembly and post-working can be performed. Post-working can include shearing followed by re-shearing or compression forming; punching with a cutting blade having a continuously reduced base width; punching with a tool having a curved blade and a protrusion at the tip of the cutting blade, where the curved blade may include a shoulder portion of given radius and/or angle; fusion cutting; etc. Tensile residual stresses after punching can be reduced and resistance to hydrogen embrittlement can be improved.

Abstract: The object of the present invention is to provide high-strength steel sheets exhibiting high impact energy absorption properties, as steel sheets to be used for shaping and working into such parts to front side members which absorb impact energy upon collision, as well as a method for their production.

Abstract: The object of the present invention is to provide high-strength steel sheets exhibiting high impact energy absorption properties, as steel materials, to be used for shaping and working into such parts as front side members of automobiles which absorb impact energy upon collision, as well as a method for their production.

Abstract: A grease composition for high-temperature, high-speed and high-load bearings comprises (i) a lubricating base oil composed of an alkyldiphenyl ether lubricant as an essential ingredient and having a kinematic viscosity of 90-160 cSt at 40.degree. C., and (ii) 22-30 wt. %, based on the grease composition, of a diurea compound as a thickener. The diurea compound is represented by the following formula: ##STR1## wherein R.sub.2 means an aromatic hydrocarbon group having 6-15 carbon atoms, R.sub.1 and R.sub.3 denote an aromatic hydrocarbon group having 6-12 carbon atoms or a linear alkyl group having 8-20 carbon atoms, and the proportion of aromatic hydrocarbon groups in R.sub.1 and R.sub.3 is 70-95 mole %. The NLGI thickness grade of said composition is in a range of from No. 1 to No. 3.

Abstract: A grease composition for a high-speed rolling bearing contains an alkyl diphenyl ether oil as a base oil, and at least one of diurea compounds represented by the formula (1) ##STR1## wherein R.sup.1 denotes a divalent aromatic hydrocarbon residue having 6 to 15 carbon atoms and R.sup.2 and R.sup.3 may be the same or different and each represent a cyclohexyl group, a cyclohexyl derivative group having 7 to 12 carbon atoms or an alkyl group having 8 to 20 carbon atoms. The diurea compound is contained as a thickener in the base oil. The content in percent of the cyclohexyl group and the cyclohexyl derivative group in the diurea compound is such that a value of [{(numbers of cyclohexyl groups and derivative groups thereof)/(numbers of cyclohexyl groups and derivative groups thereof plus numbers of alkyl groups)}.times.100] is equal to 50 to 100%.

Abstract: A process of thermally cracking a heavy petroleum oil wherein the heavy petroleum oil is treated successively in a cracking furnace and then in a perfect mixing type tank reactor. The thermal cracking in the cracking furnace is performed at a temperature at the outlet of the cracking furnace of 450.degree.-520.degree. C. with a conversion of at least 60-75% of the overall conversion rate while the thermal cracking in the tank reactor is performed at a temperature of 400.degree.-450.degree. C. a pressure of from ambient pressure to 1 kg/cm.sup.2 for a period of time of less than 30 minutes but not less than 10 minutes while feeding steam having a temperature of 435.degree.-700.degree. C. to the tank reactor in an amount of 8-20% by weight of the heavy petroleum oil fed to the cracking furnace.

Abstract: There are provided improved process and apparatus for preparing a laminated heat-shrinkable strip comprising upper and lower heat-shrinkable sheets fused together with an electric conductor wire sandwiched therebetween as means for covering and protecting joints of steel pipes of oil pipelines or cables.

Abstract: In a can body forming process and equipment therefor, the cooling action to be added to the joining portions at the opposite ends of a can body blank is effected only at the lower part of the can forming cylinder so that said joining portions can be joined substantially without undergoing internal strain and with a higher forming accuracy.

Abstract: In a can body forming process and equipment therefor, the cooling action to be added to the joining portions at the opposite ends of a can body blank is effected only at the lower part of the can forming cylinder so that said joining portions can be joined substantially without undergoing internal strain and with a higher forming accuracy.

Abstract: A can forming method and apparatus wherein cut-burrs of a can blank are removed from the ends thereof an adhesive film is stuck onto the preheated ends of the blank and, then, said ends are subjected to high-frequency induction heating for melting said films to join said ends together in such a manner as to prevent edge effect and associated deformations from occurring, thereby to form a lapped seam having a remarkably high adhesive strength substantially without pin-hole formation.