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 the internal surface and the 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 the CS values calculated from the weld metal components using the equation CS = 5.1 + 1.4[Mo] -[Ni] - 0.6[Mn] - 36.3[C] are equal to zero or more at both the internal surface side and the external surface side.
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 tem peratures.
Abstract:
Provided is a submerged arc welding method enables: welds with high toughness to be provided with low input heat; deep penetration; and a wide bead width to be sufficiently obtained in the welding of thick materials such that the welding speed is not more than 3 m/minute. The wire diameter of a first electrode at the head in the welding direction is established at 3.9 to 4.1 mm. Two electrodes are positioned on both sides of a weld line at the tail end in the welding direction. Wire tip positions of the two electrodes on the surface of a steel sheet are positioned on the same line which is perpendicular to the weld line and the distance (W) (mm) between the wire tip positions and the weld line is established at 5 to 20 mm.
Abstract:
Изобретениеотноситсяк областиметаллургии, вчастностик высокопрочнымстальнымтрубам. Предложенавысокопрочнаястальнаятрубаи способееизготовления. Трубаизготовленас применениемдвустороннейоднослойнойэлектродуговойсваркиподфлюсом, выполненнойповнутреннейповерхностии повнешнейповерхностиосновногометалла. Основнойметаллсварнойстальнойтрубыи металлсварногошваимеютпределпрочностиприрастяжении 800 МПаиливыше. Металлсварногошвасодержит, мас.%: Сот 0,04 до 0,09, Si от 0,30 до 0,50, Mn от 1,4 до 2,0, Cu менее 0,5, Ni более 0,9, номенее 4,2, Моот 0,4 до 1,6, Cr менее 0,3, V менее 0,2 иостальное Fe инеизбежныепримеси. Величина CS, рассчитаннаяисходяизсоставаметалласварногошвапоуравнению (1), равнанулюилиимеетбольшеезначениекакнавнутреннейповерхности, таки навнешнейповерхности, где . Основнойметаллсодержит, мас.%: Сот 0,03 до 0,12, Si от 0,01 до 0,5, Mn от 1,5 до 3,0, Al от 0,01 до 0,08, Nb от 0,01 до 0,08, Ti от 0,0005 до 0,024, N от 0,001 до 0,01, О: 0,004 илименее, S 0,002 илименее, Саот 0,0005 до 0,01, поменьшеймере, одинэлемент, выбранныйизгруппы, включающей Cu от 0,01 до 1,3, Ni от 0,1 до 3,0, Моот 0,01 до 1,0, Cr от 0,01 до 1,0 и V от 0,01 до 0,1 иостальное Fe инеизбежныепримеси. Высокопрочнаястальнаятрубаимеетпределпрочности 800 МПаиливыше, металлсварногошвакоторойимеетвысокоесопротивлениехолодномурастрескиваниюи высокуюнизкотемпературнуювязкость. 2 н.п. ф-лы, 2 ил., 7 табл.
Abstract:
A high-strength steel pipe of 800 MPa or greater tensile strength, having a weld metal excelling in low-temperature cracking resistance and low-tempe rature toughness. The high-strength welded steel pipe has the following feat ures. The tensile strengths of the weld metal and base metal of the welded s teel pipe manufactured through submerged arc welding of one layer on each of both sides from the inside surface and outside surface are simultaneously 8 00 MPa or greater. The weld metal consists of 0.04 to 0.09 mass% C, 0.32 to 0.50 mass% Si, 1.4 to 2.0 mass% Mn, less than 0.5 mass% Cu, over 0.9 to 4.2 mass% Ni, 0.4 to 1.5 mass% Mo, less than 0.5 mass% Cr, less than 0.2 mass% V and the balance Fe and unavoidable impurities. The CS value as calculated b y the formula CS=5.1+1.4[Mo]-[Ni]-0.6[Mn]-36.3[C] from the components of the weld metal is 0 or greater on both the internal surface side and the extern al surface side.
Abstract:
The present invention provides a welding technology that allows stable welding even if a thin wire is used as a leading electrode in multiple-electrode submerged arc welding, particularly if welding is performed under welding conditions involving high wire feeding speed, or even if a flux-cored wire is used in which large winding remains after straightening. Provided are a welding torch, for use with a leading electrode in multiple-electrode submerged arc welding, that includes a contact tip, a connector for a power cable, a tube-shaped conductor disposed therebetween, and means for insulating the tube-shaped conductor from an electrode wire, and a multiple-electrode submerged arc welding method using such a welding torch.