Resistance seam welding uses what method to create a seam?

Resistance seam welding uses what method to create a seam?

• A. Rotating wheel electrodes to make a series of overlapping spot welds along a lap joint
• B. Fixed electrodes to create a single weld
• C. Gas torch welding across a seam
• D. Laser beam welding along a joint

Answer: (A)

Resistance seam welding creates a continuous seam by using two copper wheel electrodes that rotate and travel along the joint, clamping the sheets and passing current through them. The electrical resistance at the wheel contact heats the metal, forming a weld nugget each time the wheels press together. As the wheels move, these nuggets overlap, producing a smooth, continuous weld along a lap joint. This approach is fast and well-suited for thin sheets, giving a leak-tight seam with relatively little distortion. The other options describe different welding methods: using fixed electrodes would yield a single weld location rather than a continuous seam; a gas torch weld relies on flame heat rather than electrical resistance; and laser beam welding uses a focused laser as the heat source, not wheel electrodes.

Resistance seam welding creates a continuous seam by using two copper wheel electrodes that rotate and travel along the joint, clamping the sheets and passing current through them. The electrical resistance at the wheel contact heats the metal, forming a weld nugget each time the wheels press together. As the wheels move, these nuggets overlap, producing a smooth, continuous weld along a lap joint. This approach is fast and well-suited for thin sheets, giving a leak-tight seam with relatively little distortion.

The other options describe different welding methods: using fixed electrodes would yield a single weld location rather than a continuous seam; a gas torch weld relies on flame heat rather than electrical resistance; and laser beam welding uses a focused laser as the heat source, not wheel electrodes.