The influence of process factors of butt welding flange on weld formation

When arc welding butt joints, it is usually determined whether to reserve a gap, the size of the gap and the form of the groove according to the thickness of the welding plate. When other conditions are constant, the larger the size of the groove or gap, the smaller the weld height, which is equivalent to the weld position falling, and the fusion ratio is reduced at this time. Therefore, leaving a gap or opening a groove can be used to control the size of the height and adjust the fusion ratio. Compared with the groove without a gap, the heat dissipation conditions of the two are somewhat different. Generally speaking, the crystallization conditions of the groove are more favorable.

When arc welding butt joints, it is usually determined whether to reserve a gap, the size of the gap and the form of the groove according to the thickness of the welding plate. When other conditions are constant, the larger the size of the groove or gap, the smaller the weld height, which is equivalent to the weld position falling, and the fusion ratio is reduced at this time. Therefore, leaving a gap or opening a groove can be used to control the size of the height and adjust the fusion ratio. Compared with the groove without a gap, the heat dissipation conditions of the two are somewhat different. Generally speaking, the crystallization conditions of the groove are more favorable.

When the welding wire is tilted forward, the arc force weakens the effect of the molten pool metal on the backward discharge, the liquid metal layer at the bottom of the molten pool becomes thicker, the melting depth decreases, the depth of the arc penetrating into the welding flange decreases, the arc spot movement range expands, the molten width increases, and the residual height decreases. The smaller the welding wire tilt angle α, the more obvious this effect is. When the welding wire is tilted backward, the situation is the opposite. When welding with welding rods, the electric backward tilt method is mostly used, and the tilt angle α is between 65° and 80°.