Shielded metal arc welding

About: Shielded metal arc welding is a research topic. Over the lifetime, 4462 publications have been published within this topic receiving 40560 citations. The topic is also known as: manual metal arc welding & flux shielded arc welding.

Flux-cored wire for submerged arc welding of low-temperature steel, and welding method using the same

Abstract: PROBLEM TO BE SOLVED: To provide a flux-cored wire for submerged arc welding of low-temperature steel, and a welding method using the same in which the welding workability is excellent even under a high-speed welding condition, and a weld metal of excellent mechanical performance can be obtained. SOLUTION: The flux-cored wire for submerged arc welding of low-temperature steel contains, by the wire total mass% of the flux-cored wire, 0.02-0.30% C, 0.08-0.6% Si, 1.2-3.4% Mn, 0.5-3.5% Ni, and 0.03-0.8% Mo in the total of one or both of a steel shell and filling flux; 0.01-0.27% C, 2-15% CaF 2 , and 0.05-0.7% CO 2 part of metal carbonate and the balance Fe in the steel shell, Fe in alloy powder, iron powder and inevitable impurities in the filled flux; the total hydrogen amount of the wire is ≤50 ppm, the flux filling ratio of the filled flux in the components is 10-30%, and any joint is not formed in the steel shell. COPYRIGHT: (C)2010,JPO&INPIT

The Effect of Polarity and Hydrostatic Pressure on Operational Characteristics of Rutile Electrode in Underwater Welding.

Abstract: In order to provide a better understanding of the phenomena that define the weld bead penetration and melting rate of consumables in underwater welding, welds were developed with a rutile electrode in air welding conditions and at the simulated depths of 5 and 10 m with the use of a hyperbaric chamber and a gravity feeding system. In this way, voltage and current signals were acquired. Data processing involved the welding voltage, determination of the sum of the anodic and cathodic drops, calculation of the short-circuit factor, and determination of the melting rate. Cross-sectional samples were also taken from the weld bead to assess bead geometry. As a result, the collected data show that the generation of energy in the arc-electrode connection in direct polarity (direct current electrode negative-DCEN) is affected by the hydrostatic pressure, causing a loss of fusion efficiency, a drop of operating voltage, decreased arc length, and increased number of short-circuit events. The combination of these characteristics kept the weld bead geometry unchanged, compared to dry weld conditions. With the positive electrode (direct current electrode positive-DCEP), radial losses were derived from greater arc lengths resulting from increasing hydrostatic pressure, which led to a decrease in weld penetration.

Numerical Simulation of Metal Vapor Behavior in Gas Tungsten Arc Welding

Abstract: The present modeling of a gas tungsten arc in helium or argon accounts for metal vapor contamination from the weld pool as an anode. The whole region of gas tungsten arc welding, namely, tungsten cathode, arc plasma and weld pool is treated in a unified numerical model. A viscosity approximation is used to express the diffusion coefficient in terms of the viscosities of shielding gas and iron vapor. The time dependent two-dimensional distributions of temperature, velocity and iron vapor concentration are predicted, together with the weld penetration as function of time for a 150 A arc at atmospheric pressure. It is shown that thermal plasma in gas tungsten arc is markedly influenced by iron vapor from the weld pool surface and concentration of the iron vapor into the plasma is dependent on temperature of weld pool surface.

Gas shielded metal arc welding method

Abstract: PURPOSE:To prevent weld defects by generating an arc only on a preceding wire to form a molten pool, vibrating and stirring a succeeding wire under a specified condition and using argon gas containing oxygen as shielding gas. CONSTITUTION:In gas shielded metal arc welding of galvanized steel sheets 5, the arc is generated only on the preceding wire 1 to form the molten pool 3 by using plural wires. The succeeding wire 2 is inserted into the molten pool 3 at the distance of >=2mm from the preceding wire 1C and stirred under the condition of frequency of >=0.5time and amplitude of >=0.3mm. Besides, argon gas containing oxygen less than 7vol.% or mixed gas of argon gas containing oxygen less than 7vol.% with gaseous carbon dioxide is used as shielding gas. Accordingly, the generation of pits and blowholes due to zinc vapor generated at the time of welding is prevented and sound weld metal can be obtained.

Plasma ARC weld repair of IN100 material

Abstract: A method for weld repairing airfoils made from nickel based super alloy material is provided. The method includes removing a damaged portion of the airfoil by machining the airfoil to a relatively smooth surface. Powdered alloy material, such as IN-100 material is then fed to a plasma arc welding device. A plurality of weld beads are deposited along the damaged portion of the airfoil in a continuous bi-directional pattern by the welding device to eliminate abrupt thermal transients at the ends of the weld, thereby reducing the thermal stresses that cause cracking in susceptible alloys such as IN-100.