RESISTANCE SPOT WELDING METHOD Russian patent published in 2000 - IPC

FIELD: construction; making of embedded fittings of reinforced concrete structures with lap joints. SUBSTANCE: at initial moment, parts to be welded are clamped with force whose value is 2 - 3 times less than welding force. Then welding current is passed and clamping force is increased to welding force. Prior to switching on welding current pulse, additional pulse of current whose value is 1.5 - 2 times greater than welding current value is passed through parts to be welded. Duration of additional pulse depends on weld joint area and material of welded parts. Welding force is applied at moment of switching on of welding current. EFFECT: increased capacity and reduced consumption of energy at manufacture of embedded fittings with provision of high quality of joints. 3 dwg, 1 ex