Establishing relationship between welding current and weld metal deposition rate (productivity) for metal cored tubular (MCT) wire in submerged arc welding process

Abstract

Submerged arc welding (SAW) process is used to weld large, heavy metal deposition jobs that warrant critical requirements, and this metal joining process alone is used to weld approximately 10% of the deposited weld metal worldwide. Any augmentation in productivity of SAW process, will immensely benefit the welding industry, as this process is widely used on variety of common metals & alloys. This paper focusses on establishing relationship between welding current and productivity (in terms of weld metal deposition rate as an index), for a given filler wire diameter. Productivity rates of three most commonly used SAW wire sizes Metal Cored Tubular wires were studied, at different current values, covering full current range through bead-on-plate experiments. At each current value, the bead was optimized for acceptable visual quality, by varying arc travel speed and voltage, then the wire feed rate making acceptable bead was noted. The current density, the heat input and corresponding weld metal deposition rate were calculated for establishing an empirical relationship. The established relationship can be effectively used, to estimate the productivity from the current values, for a given wire diameter.