Which statement best describes ERW as a group of processes?

Which statement best describes ERW as a group of processes?

• A. It uses heat produced by resistance to current flow to join metals under pressure
• B. It uses laser heat to join metals
• C. It requires filler metal and flux
• D. It relies on soldering

Answer: (A)

Electric resistance welding is about using heat generated by the electrical resistance of the workpieces as current passes through them, with pressure applied to forge the joint. In ERW, the metal at the interface heats up because electrical resistance converts part of the current into heat; the surfaces are pressed together so that, as the material softens or melts, the metals fuse as the heat is removed and the joint solidifies. No filler metal or flux is used, and the bond forms directly between the base metals. This differs from processes that rely on a separate heat source like a laser, or that require filler metal and flux, or that bond through soldering. The defining idea is that the heat comes from the resistance to current flow and the parts are pressed together to create the weld.

Electric resistance welding is about using heat generated by the electrical resistance of the workpieces as current passes through them, with pressure applied to forge the joint. In ERW, the metal at the interface heats up because electrical resistance converts part of the current into heat; the surfaces are pressed together so that, as the material softens or melts, the metals fuse as the heat is removed and the joint solidifies. No filler metal or flux is used, and the bond forms directly between the base metals. This differs from processes that rely on a separate heat source like a laser, or that require filler metal and flux, or that bond through soldering. The defining idea is that the heat comes from the resistance to current flow and the parts are pressed together to create the weld.