Gas-shielded welding with electrode oscillations. Thermal problem

Abstract

A method is proposed for calculating the temperature field in welding with trapezoidal oscillations of the welding arc, including the equation of the temperature field for the scheme of the moving surface heat source with normal distribution, the equation of trapezoidal oscillation in the form of the sum of Fourier series and the experimentally determined dependence of the effective radius of the heating spot of the arc r₀ on the welding conditions. The dependence of the effective radius of the heating spot of the arc r₀ on the welding conditions is determined by the similarity methods for welding of low-carbon and low-alloy steels in CO₂ and a mixture of the gases Ar + 20% CO₂. The comparison of the calculated temperatures and the results obtained in full-size experiments in welding of the pipes shows that the proposed calculation method results in sufficiently accurate determination of the temperature fields for practical applications.

Keywords:

• Arc
• temperature field
• trapezoidal oscillation waveform
• spot heating
• low-alloy steel

Notes

Selected from Svarochnoe Proizvodstvo, 2015, 68 (7) 3–8