What type of welding involves the use of tubular wire with flux inside?

The type of welding that involves the use of tubular wire with flux inside is Flux Cored Arc Welding (FCAW). This process utilizes a continuously fed tubular wire that contains a core of flux material. When welding, the flux is melted, and it provides shielding gas to protect the weld pool from atmospheric contamination, as well as serving as a source of alloying elements.

FCAW can be used either as a self-shielded process, where the flux alone provides protection, or as a dual-shielded process, where an external shielding gas is also used. This versatility allows for welding in various positions and environmental conditions, making it a popular choice for many applications.

In contrast, other welding processes mentioned – Gas Metal Arc Welding, Stick Welding, and Submerged Arc Welding – do not utilize tubular wire with an internal flux. Gas Metal Arc Welding employs solid wire and an external shielding gas, Stick Welding uses coated electrodes that provide flux during the process, and Submerged Arc Welding involves the use of solid wire and granular flux but does not utilize a tubular wire. Each of these methods has its unique characteristics and applications, but when it comes to tubular wire with flux inside, Flux Cored Arc Welding is the correct answer.