Gun-to-cable assemblies generally are much heavier than those used in GMAW applications. If large diameter wire is contemplated, then a power supply of 500-650 amperes may be necessary for maximum productivity. In semiautomatic welding, the equipment is generally the same as that used for GMAW processes, see SES W07-F01. Out-of-position welding is possible with 15.2 mm (0.60 in) diameter and smaller electrodes.Ĥ.3 Equipment. With the availability of small diameter electrode 0.889/1.143 mm (0.035/0.045 in) piping applications down to 76.2 mm (3 in) diameter and open root weld preparation are realistic, but high skill is required. The process is used to produce weldments conforming to the ASME Code. With the advent of the ‘metal core’ electrode types, there is little slag to remove and deposition rates are further improved. Higher productivity is the chief appeal of FCAW for many applications. The disadvantage is the weight that is added to the gun.Ĥ.2 Applications. The exhausting nozzle encircles the gun nozzle and is ducted to an exhaust pump and filter cannister. Several manufacturers have also introduced welding guns equipped with fume extractors built into them. The use of forced ventilation devices is usually necessary as much for general shop atmosphere as for the welder’s well being. Proper positioning of the welder’s head and the use of a curved front welding hood will greatly reduce the smoke/fume that will reach the breathing zone.
This process produces more smoke than shielded metal arc welding process with covered electrode however, much more weld metal is deposited per unit of arc time.
Follow safe practices prescribed.ģ.4 One significant safety factor in FCAW is the amount of smoke and fume produced. Both the particular operating characteristics of the process and the resulting weld properties are controlled by the flux being encased in a metallic sheath.ģ.3 Safety. The feature that distinguishes FCAW process from other arc welding processes is the enclosure of fluxing ingredients within a continuously fed electrode. Shielding is provided by a flux contained within the tubular electrode and may or may not be supplemented by an externally shielding gas.ģ.2 Fundamentals. The Complete Guide to Flux-Cored Arc Welding | What is FCAWģ.1 FCAW process produces the fusion of metals by heating them with an arc between a continuously fed filler metal (consumable) electrode and the work. Hobart Filler Metals has taken on the challenge of producing a flux-cored wire that provides the excellent toughness and low oxygen levels of a basic flux-cored wire or stick electrode with operability and out-of-position welding capabilities that are closer to those of rutile-based flux-cored wire.3. As a consequence, many users will opt for EXX18 shielded metal arc welding (SMAW or “stick”) electrodes to achieve good toughness and all-positional capabilities, thereby sacrificing the high productivity that can be achieved with a flux-cored product. Furthermore, as weld metal tensile strength increases, it is common to see a drop-off in impact toughness. Because the weld deposits tend to be relatively high in oxygen, however, impact toughness will typically be much lower than what can be achieved with a basic slag system. Rutile-based FCAW electrodes, such as EXXT-1 and EXXT-12, offer smooth operation and good all-positional capabilities. What’s more, the puddle tends to be too fluid for out-of-position welding. Basic flux-cored arc welding (FCAW) electrodes of the EXXT-5 designation offer excellent toughness and weld metal cleanliness, however the operation of most T-5 electrodes is very harsh with high levels of spatter. Producing a very clean, low-oxygen weld deposit has long been a goal of welding consumable manufacturers.
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