How are FCAW wires manufactured?

• A. By passing metal strips through contour forming rolls that bend the strip into a U shape, inserting the core material, closing rolls to form a tube while tightly compressing the core, then pulling the tube through drawing dies to reduce diameter; final sizes vary from 0.045" to 1/8"
• B. By casting from molten metal into a solid wire
• C. By twisting filaments of metal
• D. By extruding flux around a solid core

Answer: (A)

FCAW wires are made as flux‑cored tubes rather than solid wires or coated strands. The outer shell is formed from metal strips into a hollow tube, and the flux material is packed inside the tube. After inserting the flux, the tube is closed and the core is tightly compressed, then the tube is drawn through drawing dies to achieve the final diameter. This method yields the typical flux‑cored wire with a flux core and outer metal sheath, usually in sizes from about 0.045 in to 1/8 in.

Other manufacturing ideas don’t produce this tubular, flux‑filled electrode. Casting molten metal would create a solid wire, not a hollow flux core. Twisting filaments makes stranded conductors, not a flux‑filled tube. Extruding flux around a solid core would give a coated solid wire, not a hollow flux‑cored one.