METHOD OF CHECKING QUALITY OF RESISTANCE SPOT WELDING Russian patent published in 1997 - IPC

FIELD: mechanical engineering checking quality of spot welding of steel sheets with coatings. SUBSTANCE: method comes to measuring current values of welding parameters, plotting mathematical model of process and calculating by model geometric sizes of nugget and checking additionally value of change of cast nugget caused by reduction of electrodes stability in process of welding. "N" weld spots are made and relationship Δd = f(n) between variations of initial sizes of cast nugget and number of weld spots is determined by destruction method after which corrections are introduced into geometric sizes of cat nugget according to formula d_n= d-Δd. Having obtained minimum tolerable size, welding parameters are corrected. EFFECT: provision of required strength of welded joints. 1 dwg