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WIRE WELDING

In flux cored arc welding the heat is obtained from an arc between a continuous flux cored wire and the work. The flux provides gas shielding for the arc and a slag covering of the weld deposit.

means of making electrical contact with the core wire and coiling it without cracking the brittle coating. The need for a continuous arc welding electrode led to the development of the self shielding flux cored wire where the material needed for shielding is contained inside the core of a hollow wire.

The self-shielded flux-cored arc welding process is a development from the shielded metal arc welding. The versatility and maneuverability of stick electrodes in manual welding stimulated efforts to mechanize the process allowing a continuous wire electrode to be used. A continuous electrode would eliminate the welding time lost in changing electrodes and would eliminate the material lost in electrode stubs. The main problem with a continuous coated electrode is to find suitable

The "inside-out" construction of the flux cored wire solved both problems. Continuous electrical contact can be made with the wires at any distance from the arc and they can be coiled and packaged on any of the standard spools used for filler wire. The outcome of these efforts was the development of the semiautomatic and full-automatic processes for welding with continuous flux-cored tubular "wires". Such wires contain in their cores the ingredients for fluxing and deoxidizing molten metal and

Flux Cored Arc Welding Self-Shielded.

(FCAW) Self-Shielded .

The arc:

4.03

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