INFLUENCE OF WELDING PARAMETERS- -ON WELD READ GEOMETRY, IN VERTICAL POSITION MAG WELDING WITH k2 mm. SOLID & FLUX CORED WIRE

Abstract

In positional welding especialy in the vertical position, it is difficult to weld because of the flow of the molten metal in the downward direction due to the effect of gravity. In Gas metal arc welding (GMAW) (were) the current densities are higher and molten droplet attains relatively high temperatures thus attaining higher fluidity, it is difficult to weld in vertical position than compared to Manual Metal Arc Welding. Investigations have been carried out to study the influence of the welding parameters on the weld bead geometry and percentage dilution in the vertical down position to compare to flat position welding. It was found to be very difficult to weld in the vertical up position over wider range of welding parameters because vertical up welding was possible in a very narrow range of welding parameters. Investigations have revealed that in vertical down position with in a certain range of welding current, voltage and welding speed the weld bead geometry parameters such as depth of penetration, weld width and height of reinforcement are influenced in the same way as in the flat position. Beyond these ranges of welding parameters the weld bead geometry has appreciably influenced by welding positions. There is an appreciable influence of solid wire over flux cored wire in size 0',' of weld bead geometry. The percentage dilution also influence by welding position as well as ,the type of the wire i.e. solid or flux cored wire. The percentage dilution is generaiy lower in vertical dawn position as compared to fiat position for solid wire. But there is no definite trend for flux, cored wire. Further with flux cored wire the lower percentage dilution is observed in flat position, but higher percentage dilution were obtained in vertical posit!on as compared to solid wire under similar welding conditions