Abstract:
Resistance Spot Welding is a process of joining the sheet
metal parts. In this study spot welding machine is used to weld the
pads on a pan of the fuel tank. Material used in fuel tank’s pan and
pad is Cold Reduced Low Carbon Steel Sheet. The thickness for pad
is 1.50 mm and for pan is 0.80 mm (Galvanized). The diameter of
electrode used for spot welding is 5mm. There is a rejection of fuel
tank due to low weld tensile strength. So, DMAIC (Define, Measure,
Analyse, Improve & Control) method and Taguchi Method is used
for reduction in rejection level. Experiment is carried out on
Resistance Spot Welding machine. The highly effective parameters
as welding current and weld cycle time with their different levels are
used. These parameters are affecting the quality of resistance spot
welding in terms of tensile strength, nugget size and internal defect.
Each parameter has its effect on output quality parameter. The
purpose of this study is to find out the effect of two control
parameters like welding current and weld cycle time of resistance
spot welding machine on tensile strength, nugget size and internal
defect of the spot welding as a weld quality. Ultrasonic Flaw
Detection Test as a Non-Destructive test and Tensile Test as a
Destructive test is used. Optimization of welding current and cycle
time by using software is used for reduction in rejection level.
