Knowledgeable designers recognize such cost-saving and quality-improvement methods and specify them in the manufacturing process. The consistency attainable with such methods surpasses that of sophisticated jigs and fixtures but the greatest value is the cost efficiency. Additionally, these techniques can be used for fillet welding applications, and mechanical assemblies. A refinement of resistance spot welding is resistance projection welding (RPW). It makes use of projections previously formed on the workpiece to reduce the power required to make a resistance weld. Consequently, multiple welds can be made more easily at the same time, and thicker sections can be joined more readily than in RSW. Other advantages include reduced shunting effects, closer weld-to-weld spacing and welding of workpieces with smaller flanges.
Position the welding torch with the wire in the center of the hole contacting the back sheet of metal. It is important to arc against this back sheet rather than on the edge of the hole, otherwise the weld might not penetrate into the back sheet. The torch should ideally be pointing directly into the hole rather than at the angle in the photograph. Start welding in this position and don’t move the welder until the hole is almost full of weld. Then move the welder outwards in ever increasing circles until the weld is completed.
Where is Spot Welding Used? Spot welding has applications in a number of industries, including automotive, aerospace, rail, white goods, metal furniture, electronics, medical building and construction. Given the ease with which spot welding can be automated when combined with robots and manipulation systems, it is the most common joining process in high volume manufacturing lines and has in particular been the main joining process in the construction of steel cars for over 100 years. Read extra details at https://www.weldingsuppliesdirect.co.uk/welding-equipment/spot-welding.html.
Portable spot welders are compact, lightweight and handy for difficult-to-access joints. As such, they are most commonly used in coachbuilding. They have an average welding capacity of 2 + 2mm and are relatively inefficient due to the fact that the electrodes aren’t cooled between cycles. Automatic adjustment makes it easier to adjust the spot parameters according to the thickness of sheet and welding head used.