Flux cored arc welding is a process which produces coalescence by
means of an arc between a continuous consumable electrode and the
work surface. Shielding is provided by flux contained within the
tubular electrode. Additional shielding may be obtained from a gas
or gas mixture.
Introduction
A flux-cored wire is optimised to obtain performance not
possible with a solid wire. A flux-cored wire can do it better and
faster for many welding applications like :
vertical-up weldingflat weldingwelding over galvanizedwelding
hard-to-weld steels
Introduction
The flux in the core stabilised the arc, and contains deoxidisers,
scavengers, slag and vapour-forming ingridents. Gas shielded FCAW
electrodes must be supplemented with shielding gas supply
(Typically CO2).Electrode sizes range from 0.5 to 4 mm.FCAW require
more electrod extention than GMAW due to the higher current density
requirement. If the extention is not sufficient it can create
porosity in the weld.Due to the higher current density deposition
rates in FCAW ishigher than GMAW.The presence of flux and
consequential slug provide further protection. FCAW can be used
outdoors.FCAW is suitable for mechanisation and automation.
Advantages
Continuous and automatic electrode feeding Can weld a variety of
jointsHigh deposition rates Deeper penetration than
SMAWHigh-quality Less pre-cleaning than GMAWSlag covering helps
with larger out-of-position weldsSelf-shielded FCAW is draft
tolerant.
Limitations
Slag must be removedMore smoke and fumes than GMAW and
SAWSpatterFCAW wire is more expensive Equipment is more expensive
and complex than for SMAW
FCAW Process
FCAW Process
FCAW Electrode Classification
E70 T - 1
Electrode
Minimum UTS
70,000 psi
Position
Flux Cored /Tubular
Electrode
Type Gas, Usability
and Performance
American Welding Society Specification
AWS A5.20 and AWS A5.29.
FCAW Electrode Classification
E71T-1 (FCAW-G): Highest deposition rates out-ofposition.E71T-8
(FCAW-S): Highest deposition rates out-ofposition without a
shielding gas.E70T-4 (FCAW-S): Highest deposition rates in the flat
position.E70T-1 (FCAW-G): Highest deposition rates in the flat
position with Charpy properties.E71T-14 (FCAW-S): Fastest travel
speed on galvanized and coated steels.E70T-5 (FCAW-G): Fastest way
to weld hard-toweld steels.
Electrode E71T-1
also offer an exceptionally smooth welding arc and minimal
spattereven with 100% carbon dioxide shielding gasArgon/carbon
dioxide blends are used for the smoothest arc and best
out-of-position performance
Electrode E71T-8
offer the highest deposition ratesin the vertical-up position, 50%
fastersince this wire is self-shielded, it is widely used outdoors
and in field erection of structural steel
Electrode E70T-4
in the flat position, the fastest way to join thick steel
plateoffers the highest semi-automatic deposition ratesused to join
thick steels where there is no Charpy impact toughness
requirementthis wire is also selfshielded, allowing it to be easily
used outdoors
