Optimised projection welding of steel Bars

Abstract The article presents tests aimed at optimising the welding of bars, made of steel AISI1005 (ø 4.2 mm), in a cruciform configuration (i.e. using the cross-wire welding process). The authors identified research gaps and carried out a detailed numerical analysis of these cases. The research-related calculations involved the use of SORPAS software. The new areas of research included (i) bars with protective zinc coatings having various thicknesses of 0 µm, 5 µm, 10 µm and 30 µm, (ii) various welding current rise times (up-slope) and (iii) single and multi-pulse welding cycles. The tests were carried out using a DC 1 kHz inverter welding machine; the results concerning welding up-slope times were compared with those obtainable using a conventional AC 50 Hz welding machine. The results of the study, in the form of a welding technology with various values of up-slope time, have been implemented in industry. The inventive idea is protected by patent no. P.229445 at the Polish Patent Office.