(2007). Obtaining a submerged arc welding flux of the MnO–SiO2–CaO–Al2O3 – CaF2 system by fusion. Welding International: Vol. 21, No. 7, pp. 502-511.

Obtaining a submerged arc welding flux of the MnO–SiO2–CaO–Al2O3 – CaF2 system by fusion

The invention relates to a T91 water wall tube row welding technology. The welding technology comprises the steps of (1) cleaning before welding; (2) welding material preparation: preparing welding wires and flux, and performing baking before flux use, wherein the baking temperature is in a range of 250 DEG C to 400 DEG C, and the baking time ranges from 0.5h to 3h; (3) spot welding before welding: using R317 welding wires to flat steel and T91tube electric welding, wherein the welding strips are needed to be baked; (4) preheating before welding: performing preheating before welding to enable all portions of materials to be welded to be uniform in heating; (5) tube row welding: performing welding in the condition of the 300A-320A welding current, 26V-27V welding voltage and 80mm/min-90mm/min and performing coverage with asbestos immediately after front welding seams are welded; (6) hydrogen removal after welding; (7) detection; (8) thermal treatment. The welding technology is simple and convenient to operate, covering through insulation cotton is performed after welding, and accordingly, cracks due to rapid cooling can be prevented.

T91 water wall tube row welding technology

PROBLEM TO BE SOLVED: To provide a method for highly productively manufacturing high manganese-steel with high quality, wherein generation of surface defects such as a surface crack is suppressed.SOLUTION: The method is for manufacturing high manganese-steel by continuous casting method. In the method, molten steel temperature T (unit: °C) in a molten steel container shortly before supplying hot water to a mold is controlled to satisfy the following formula (1) while casting speed Vc (unit: m/min) is selected within a range of the following formula (2): a≤T≤a+50 (1), Vc≥0.02×(T-a) (2). Here, a is a value determined by the following formula (3) based on the composition of the steel. (C%), etc., in the formula are respectively contents of C, etc., (unit: mass%) in the chemical composition: a=1562-{62×(C%)+6×(Si%)+4.1×(Mn%)+1.5×(Cr%)} (3).

Method for manufacturing high manganese-steel

The invention relates to a laser welding method for a thin stainless steel composite plate. According to the structural characteristics of the thin stainless steel composite plate, the outside of carbon steel is wrapped with a stainless steel plate, the stainless steel plate is thin, large-area and elastic, and great difficulty in double-sided welding is caused. By the aid of the laser welding method, the thin stainless steel plate is firstly pretreated and smoothly mounted, welding powder is prepared, argon shield is realized, the feeding quantity of the welding powder and the strength of a laser beam are controlled by means of computer program, and welding of the thin stainless steel composite plate is made possible. The welding method is advanced in process, high in welding quality, fine in corrosion resistance and high in welding strength, provides full and accurate data, and is safe, stable and reliable. The average tensile strength of a welding joint reaches 450.9MPa and accounts for 98.2% of that of base metal, the welding blank of the thin stainless steel composite plate is filled, and the laser welding method for the thin stainless steel composite plate is quite ideal.

Laser welding method for thin stainless steel composite plate

To provide weld metal that has a high strength and toughness in the as-welded condition or in the annealed condition. The weld metal of the present invention contains by weight %, C: 0.04-0.15%, Si: 0.50% or less, Mn: 1.0-1.9%, Ni: 1.0-4.0%, Cr: 0.10-1.0%, Mo: 0.20 to 1.2%, Ti: 0.010-0.060%, Al: 0.030% or less, O: 0.15-0.060%, N: 0.010% or less, Fe and inevitable impurities as the remaining contents. The weld metal is further characterized by the fact that the ratio of Ti content (%) to Si content (%) i.e.,[compound type Ti]/[compound type Si] is more than 1.5, and the number A defined by the following formula is 0.50 or more, wherein A=[Ti]/([O]−1.1×[Al]+0.05×[Si]).

Weld metal and welded structure having weld joints using the same

PROBLEM TO BE SOLVED: To provide a submerged arc welding application method for austenitic stainless steel which gives the same tensile strength as base metal; 600 N/mm2 and over, to the submerged arc weld of austenitic steel which has tensile strength: 600 N/mm2 and over, giving excellent hot-crack resistant property and bending resistant property, thereby enables to carry out double-sided one pass submerged arc welding to the plate thickness: 12-25 mm. SOLUTION: The chemical composition of weld is controlled to be the composition which includes in weight %, Cr: 19-23%, Ni: 11-15%, Mo: 1.0-1.4% N: 0.10-0.20%, C: 0.06% and below, Si: 1.00% and below, Mn: 0.5-2.50%, P: 0.040% and below, S: 0.03% and below, satisfying quantity of ferrite: 3-20% and below, and the residue consisting of substantially Fe. In double-sided one pass welding, gas metal arc welding(GMAW) is carried out after backside gouging, after that, backside submerged arc welding is carried. Otherwise before right side submerged arc welding, welding by GMAW in a groove for sealing is carried, after that right side submerged arc welding is carried out. Right side welding heat input shall be larger than backside welding heat input.

Submerged arc welding application method and welding material for austenitic stainless steel

PROBLEM TO BE SOLVED: To provide a welding material in which the weld zone of steel having excellent weather resistance has excellent seashore weather resistance in high flying salt content environment SOLUTION: In the welding material for welding weather resistant steel used in high flying salt content environment, the deposited metal has a chemical composition containing, by mass, 005 to 100% Cu, 020 to 500% Ni, 010 to 150% Cr and 005 to 100% Mo, and also, Peq obtained by the following formula (1) is 15 to 40%, and Ceq obtained by the formula (2) is 030 to 055%: Peq= Cu(%)+Ni(%)+Cr(%)+Mo(%) (1), and Ceq=C(%)+Mn(%)/6+Si(%)/24+ Ni(%)/40+Cr(%)/5+Mo(%)/4 (2)

Welding material for seashore weather resistant steel

PROBLEM TO BE SOLVED: To provide a submerged arc weld metal of high tensile strength steel having a tensile strength of ≥900 MPa, which is subjected to multilayer build up welding by submerged arc welding in the combination of solid wire and bond flux, from which satisfactory strength and stable toughness can be obtained, and whose working property in welding is satisfactory, and which is free from welding defects. SOLUTION: The submerged arc weld metal of high tensile strength steel obtained by being subjected to multilayer build up welding by submerged arc welding in the combination of solid wire and bond flux has a composition comprising per total mass of the weld metal, by mass, 0.04 to 0.09% C, 0.20 to 0.35% Si, 1.6 to 2.3% Mn, 2.5 to 3.0% Ni, 0.55 to 1.0% Cr and 0.55 to 1.0% Mo, and comprising ≤0.20% Cu, ≤0.022% O and ≤0.006% N, and the balance Fe with inevitable impurities. COPYRIGHT: (C)2008,JPO&INPIT

Submerged arc weld metal of high tensile strength steel

PROBLEM TO BE SOLVED: To provide a welded structure having a sound nonmagnetic welded joint and also to provide its manufacturing method. SOLUTION: The following is provided: the welded structure in which a base material is composed of a steel material containing 7.50 to 10.50% Ni and 18.00 to 20.00% Cr and having ≥0 Ni-bal. and, further, the tensile strength, yield point or proof stress and magnetic permeability in the base material and a weld zone are made to ≥490 N/mm 2 , ≥315 N/mm 2 and ≤1.027, respectively. It is desirable that the weld metal of the structure has a composition consisting of, by mass, ≤0.1 C, ≤0.6 Si, ≤3.5% Mn, ≤0.02% P, ≤0.01% S, 0.1% Cu, 10 to 80% Ni, 1 to 23% Cr, ≤10% Mo, at least one kind among ≤0.75% Ti, ≤4.5% Nb and ≤4.5% Ta and the balance Fe with impurities and satisfying inequalities, 0.01≤C(2Ti+Nb+0.5Ta) and C/(2Ti+Nb+0.5Ta)≤0.2. COPYRIGHT: (C)2004,JPO

Welded structure and its manufacturing method

PROBLEM TO BE SOLVED: To provide a solid wire for welding high tensile strength steel, which is applied to a building structure, and with which the tensile strength of a weld metal is ≥900 MPa and stable toughness can be obtained, and a weld zone of high quality free from welding defects can be obtained, and to provide a gas-shielded arc welding method for high tensile strength steel. SOLUTION: The solid wire has a composition comprising, by mass% to the whole mass of the wire, 0.04 to 0.12% C, 0.25 to 0.55% Si, 1.5 to 2.5% Mn, 2.5 to 3.5% Ni, 0.7 to 1.2% Cr, 0.55 to 0.90% Mo, 0.005 to 0.10% Ti and >0.01 to 0.035% Al, and comprising ≤0.012% P, ≤0.008% S and ≤0.006% N, and the balance Fe with inevitable impurities. The solid wire further comprises, by mass% to the whole mass of the wire, one or more kinds selected from V and Nb by 0.005 to 0.035% in total. COPYRIGHT: (C)2008,JPO&INPIT

Nishimura Satoru

Papers

Submerged arc welding application method and welding material for austenitic stainless steel

Welding material for seashore weather resistant steel

Submerged arc weld metal of high tensile strength steel

Welded structure and its manufacturing method

Solid wire for welding high tensile strength steel and gas-shielded arc welding method for high tensile strength steel