Abstract: A multi-electrode submerged arc welding method enables, in multi-electrode submerged arc welding using five or six electrodes, a deep penetration and a large amount of deposit metal to be obtained by supplying a large current, and enables stable arc to be generated by respective electrodes by suppressing magnetic interference. Welding defects can be prevented, beads with a good shape or appearance can be obtained, and the welding speed can be increased.

Abstract: Provided is a solid wire for gas metal arc welding, which has a small amount of fume during welding and is suitable as a welding material for high Mn steel materials. The wire has a chemical composition containing, in mass %, C: 0.2% to 0.8%, Si: 0.15% to 0.90%, Mn: 17.0% to 28.0%, P: 0.03% or less, S: 0.03% or less, Ni: 0.01% to 10.00%, Cr: 0.4% to 4.0%, Mo: 0.01% to 3.50%, B: less than 0.0010%, and N: 0.12% or less, with the balance consisting of Fe and inevitable impurities. It may contain at least one selected from V, Ti, Nb, Cu, Al, Ca and REM, if necessary. The wire has excellent manufacturability, can significantly suppress the amount of fume generated during gas metal arc welding, and can easily manufacture a weld joint having high strength and excellent impact toughness at cryogenic temperatures.

Abstract: Provided are a method of full body cutting a brittle material without via the bend-breaking step, an apparatus of cutting a brittle material, a method of manufacturing a brittle material, and a cut brittle material. A method of cutting a brittle material, the method comprising: a conveyance cutting step of converging and irradiating an infrared ray to the brittle material linearly along a line using an infrared line heater while moving the infrared line heater relative to the brittle material in a direction along the line, thereby cutting the brittle material along the line.

Abstract: A multi-electrode submerged arc welding method enables, in multi-electrode submerged arc welding using five or six electrodes, a deep penetration and a large amount of deposit metal to be obtained by supplying a large current, and enables stable arc to be generated by respective electrodes by suppressing magnetic interference. Welding defects can be prevented, beads with a good shape or appearance can be obtained, and the welding speed can be increased.

Abstract: Provided are a method of full body cutting a brittle material without via the bend-breaking step, an apparatus of cutting a brittle material, a method of manufacturing a brittle material, and a cut brittle material. A method of cutting a brittle material, the method comprising: a conveyance cutting step of converging and irradiating an infrared ray to the brittle material linearly along a line using an infrared line heater while moving the infrared line heater relative to the brittle material in a direction along the line, thereby cutting the brittle material along the line.

Abstract: The present invention provides a submerged arc welding method attempting to enhance toughness of a welded zone with low heat input and capable of achieving deep penetration and a sufficiently wide bead width in welding a thick material at a weld speed of 3 m/min or less. In the submerged arc welding method, a first electrode at the head in a welding direction has a wire diameter of 3.9 to 4.1 mm, two electrodes are arranged on both sides holding a weld line therebetween at the tail end in the welding direction, the wire tip positions of the two electrodes on a surface of the steel plate are arranged on the same line vertical to the weld line, and a distance W (mm) between each of the wire tip positions and the weld line is 5 to 20 mm.

Abstract: Provided are a combination welding method and a combination arc welding machine thereof having excellent construction efficiency and preventing a deterioration of toughness of a HAZ by maintaining the current density of each of gas metal arc welding and submerged-arc welding within an appropriate range at the time of welding a steel plate by the combination of the gas metal arc welding using multielectrodes and the submerged-arc welding using multielectrodes. The gas metal arc welding is performed using two or more electrodes, a wire for welding having a wire diameter of 1.4 mm or more is used in the first electrode of the gas metal arc welding, and a current density of the first electrode is set to 320 A/mm2 or more.

Abstract: The present invention provides a submerged arc welding method attempting to enhance toughness of a welded zone with low heat input and capable of achieving deep penetration and a sufficiently wide bead width in welding a thick material at a weld speed of 3 m/min or less. In the submerged arc welding method, a first electrode at the head in a welding direction has a wire diameter of 3.9 to 4.1 mm, two electrodes are arranged on both sides holding a weld line therebetween at the tail end in the welding direction, the wire tip positions of the two electrodes on a surface of the steel plate are arranged on the same line vertical to the weld line, and a distance W (mm) between each of the wire tip positions and the weld line is 5 to 20 mm.

Abstract: Provided is a submerged arc welding method for a steel plate. In welding the steel plate from an internal surface or an external surface by a submerged arc welding, welding condition is set such that, a cross-sectional area of internal weld metal S1 and a cross-sectional area of external weld metal S2 satisfy the formula (1), the formula (2), and the formula (3), that is, 0.40?(S1+S2)/t2?0.80 . . . (1), S1/t2?0.35 . . . (2), and S2/t2?0.45 . . . (3), wherein t is a plate thickness of the steel plate (mm), S1 is a cross-sectional area of the internal weld metal (mm2) excluding the cross-sectional area of a portion of the internal weld metal overlapping with the external weld metal after external welding, and S2 is a cross-sectional area of the external weld metal (mm2).

Abstract: Disclosed is a submerged arc welding method capable of an attempt to enhance toughness of a welded zone with low heat input and an attempt to decrease a weld reinforcement height by suppressing excessive melting of a wire, and capable of achieving a deep depth of penetration and a wide bead width. In the submerged arc welding method, a first electrode at the head in a welding direction has a wire diameter of 2.0 to 3.2 mm and a current density of 145 A/mm2 or more, second and subsequent electrodes are arranged behind the first electrode in a line, and a groove formed in a steel plate has a two-step groove shape satisfying ?B<?T where ?B is a groove angle of a bottom layer, and ?T is a groove angle of a surface layer.

Abstract: Steel is subjected to multiple-electrode submerged arc welding with three or more electrodes in which a direct-current power source is used to supply current to a first electrode, the welding by the first electrode is carried out at a current density of 250 A/mm2 or more, preferably with a wire diameter of 3.2 mm or less and a weld current of 1,000 A or more, the welding by the second electrode is carried out at a current density of 150 A/mm2 or more, preferably with a weld current of 600 A or more, one of the interelectrode spacings is 23 mm or more on a surface of the steel, and the remaining interelectrode spacings are 20 mm or less.

Abstract: Provided is a submerged arc welding method for a steel plate. In welding the steel plate from an internal surface or an external surface by a submerged arc welding, welding condition is set such that, a cross-sectional area of internal weld metal S1 and a cross-sectional area of external weld metal S2 satisfy the formula (1), the formula (2), and the formula (3), that is, 0.40?(S1+S2)/t2?0.80 . . . (1), S1/t2?0.35 . . . (2), and S2/t2?0.45 . . . (3), wherein t is a plate thickness of the steel plate (mm), S1 is a cross-sectional area of the internal weld metal (mm2) excluding the cross-sectional area of a portion of the internal weld metal overlapping with the external weld metal after external welding, and S2 is a cross-sectional area of the external weld metal (mm2).

Abstract: A high-strength steel pipe has a tensile strength of 800 MPa or more and includes a weld metal having high cold-cracking resistance and high low-temperature toughness, wherein the weld metal contains C: 0.04% to 0.09% by mass, Si: 0.32% to 0.50% by mass, Mn: 1.4% to 2.0% by mass, Cu: less than 0.5% by mass, Ni: more than 0.9% by mass but not more than 4.2% by mass, Mo: 0.4% to 1.5% by mass, Cr: less than 0.5% by mass, V: less than 0.2% by mass, and the remainder of Fe and incidental impurities, and CS values calculated from the weld metal components using the equation CS=5.1+1.4[Mo]?[Ni]?[Mn]?36.3[C] are equal to zero or more at both an internal surface and an external surface.

Abstract: Provided are a combination welding method and a combination arc welding machine thereof having excellent construction efficiency and preventing a deterioration of toughness of a HAZ by maintaining the current density of each of gas metal arc welding and submerged-arc welding within an appropriate range at the time of welding a steel plate by the combination of the gas metal arc welding using multielectrodes and the submerged-arc welding using multielectrodes. The gas metal arc welding is performed using two or more electrodes, a wire for welding having a wire diameter of 1.4 mm or more is used in the first electrode of the gas metal arc welding, and a current density of the first electrode is set to 320 A/mm2 or more.

Abstract: Steel is subjected to multiple-electrode submerged arc welding with three or more electrodes in which a direct-current power source is used to supply current to a first electrode, the welding by the first electrode is carried out at a current density of 250 A/mm2 or more, preferably with a wire diameter of 3.2 mm or less and a weld current of 1,000 A or more, the welding by the second electrode is carried out at a current density of 150 A/mm2 or more, preferably with a weld current of 600 A or more, one of the interelectrode spacings is 23 mm or more on a surface of the steel, and the remaining interelectrode spacings are 20 mm or less.

Abstract: A lead-free low-melting-point glass having an acid resistance, being substantially free of PbO and including 12 to 35 mass % of SiO2, 3 to 20 mass % of B2O3, 35 to 75 mass % of Bi2O3, and 0 to 8 mass % of at least one material selected from the group consisting of Li2O, Na2O and K2O is provided. A lead-free low-melting-point glass composition including a powder of the glass and a filler made of a ceramic powder is also provided.

Abstract: In a production process of an organic-inorganic hybrid glassy material, the invention relates to a process for producing an organic-inorganic hybrid glassy material, characterized in that the process comprises at least the three steps of producing a gel body by a sol-gel method; melting by heating; and aging, and it relates to an organic-inorganic hybrid glassy material produced by this process.

Abstract: A high-strength steel pipe having a tensile strength of 800 MPa or more that includes a weld metal having high cold-cracking resistance and high low-temperature toughness is provided. The high-strength steel pipe is a high-strength welded steel pipe in which the welded steel pipe is manufactured by double one layer submerged arc welding performed on an internal surface and an external surface of a base metal, both the base metal of the welded steel pipe and a weld metal have a tensile strength of 800 MPa or more, the weld metal contains C: 0.04% to 0.09% by mass, Si: 0.32% to 0.50% by mass, Mn: 1.4% to 2.0% by mass, Cu: less than 0.5% by mass, Ni: more than 0.9% by mass but not more than 4.2% by mass, Mo: 0.4% to 1.5% by mass, Cr: less than 0.5% by mass, V: less than 0.2% by mass, and the remainder of Fe and incidental impurities, and CS values calculated from the weld metal components using the equation CS=5.1+1.4[Mo]?[Ni]?0.6[Mn]?36.

Abstract: In a production process of an organic-inorganic hybrid glassy material, the invention relates to a process for producing an organic-inorganic hybrid glassy material, characterized in that the process comprises at least the three steps of producing a gel body by a sol-gel method; melting by heating; and aging, and it relates to an organic-inorganic hybrid glassy material produced by this process.

Abstract: The invention relates to a lead-free, low-melting glass for covering a substrate. This glass contains 0.1-25 wt % of SiO2, 1-50 wt % of B2O3, 1-45 wt % of ZnO, 20-90 wt % of Bi2O3, 0.1-40 wt % of V2O5, 0-5 wt % of Nb2O5, 0-20 wt % of R2O where R is Li, Na or K, and 0-20 wt % of RO where R is Mg, Ca, Sr or Ba. This glass has a thermal expansion coefficient of from 65×10−7/° C. to 101×10−7/° C. within a range of 30-300° C.; and has a softening point of not higher than 630° C.