Flux-Core Arc Welding (FCAW)

FLUX-CORE ARC WELDING (FCAW)

The Process:-

Flux-core arc welding (FCAW) is similar to GMAW, as shown in Figure a. However, as shown in Figure b, the wire electrode is flux cored rather than solid; that is, the electrode is a metal tube with flux wrapped inside. The functions of the flux are similar to those of the electrode covering in SMAW, including protecting the molten metal from air. The use of additional shielding gas is optional.

Flux-Core Arc Welding (FCAW) (a) overall process (b) welding area enlarged

Advantages of FCAW:-

High deposition rates
Deeper penetration than SMAW
High quality welds
Less pre-cleaning than GMAW
Slag covering helps with out-of-position welds
Self-shielded FCAW is draft tolerant

Disadvantages of FCAW:-

Slag must be removed
Higher fume generation than GMAW and SAW
Spatter
Equipment is more expensive and complex than SMAW
FCAW wire is more expensive

Types of continuous wire electrodes:-

Comments

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