DESIGN DATA ON PRODUCTION METHODS 

 PREPARATION OF MATERIALS FOR RESISTANCE WELDING 



263 



Fig. 544. 



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Fig. 545. 



Fig. 546. 



Fig. 549. Fig. 547. Fig. 548. 



Fig. 544. — Elongated projections that cross each other are for the lightest gages and certain nonferrous combina- 

 tions and where a good strong weld is imperative. 



Fig. 545. — Elongated projections or a pattern of ribs that cross one another gives many points of small welded 

 area. Should be used for thin sheet metal. 



Fig. 546. — Elongated projection for welding to a curved surface. This assures ample contact surface in the 

 direction in which movement is likely to occur. 



Fig. 547. — Upsetting a tube to form bulges can be done by heating and upsetting on a butt welder. 



Fig. 548. — Rods of almost any metal can be upset to provide increased sections or limiting rings. 



Fig. 549. — Offsetting helps to locate the lap joint and also contributes to having one side smooth. 



Fig. 550. 



^ . f™n 



blade. 



Fig. 552. 



Fig. 550. — Welding both sides of a box form simultaneously, by employing a shunt-block device. 

 Fig. 551. — An example of "pry-bar" welding. Done by prying against parts backed up by dies. 

 Fig. 552. — Coined switch contacts having three conical projections that nest in a ring groove stamped in the 



M 



^ 



Wire cable ^ 



^ 



Fig. 553. Fig. 554. Fig. 555. 



Fig. 553. — When wire cables are "cut" by clamping between the jaws of a welder and burning the cable in two, 

 a globule of metal, formed on the ends, holds the wires together. 



Fig. 554. — Pipe or heavy-walled tubes can be butted together or to other pieces. Chamfering the pipe ends 

 keeps flash at a minimum. 



Fig. 555. — Rods or cables can be economically welded into sleeves or ferrules. 



