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 Flux-Cored-Arc Welding (FCAW)This process is a variation of GMAW. Electrodes comprise a metal sheath surrounding a core of fluxing and alloying coin pounds. Sell-shielded (FCAW-SS), it uses gas generated by bleak down of a powder-flux core inside the wire to shield the weld. Gas shielded (FCAW-SS), external gas supplies shielding.The compounds in the electrode perform essentially the same functions as the coating of a covered electrode used in SMAW: to form a floating slag coating on the weld pool to protect the weld as it solidifies; deliver deoxidizer and scavengers to help purify the weld: deliver are stabilizers to minimize spatter; add alloying elements to the weld, for optimum mechanical properties; and provide shielding gas. Filler-metal selection for FCAW depends on base-metal composition, cleanliness of base metal, thickness, a0d service. AWS specifications: A5.20, Specification for Carbon Steel Electrodes for Flux-cored Arc Welding, for low-carbon steel up to 0.15 C and mild steel 0.15 to 0.29 C; A5.29, Specification aircompressorreceivertanls for Low Alley Electrodes for Flux-cored Arc Welding, for steel of higher carbon content and the low-alloy aircompressorreceivertanls types; A5.22, Specification for Flux-cored Corrosion-Resisting Chromium and Chromium-Nickel Steel Electrodes, for stainless steels.Gas-Tungsten-Arc Welding (GTAW, TIG)GTAW rises an arc between a nonconsumable electrode and the work. It joins with or without filler metal. AWS A5.12 lists electrode types and sizes. All are tungsten, some with thoria, zirconia, ceria, or lanthana added. Thoria provides higher current-carrying aircompressorreceivertanls capacity than prime tungsten with less contamination of the weld pool. Other benefits: better arc start, greater arc stability. Zirconiated electrodes perform well with alternating current: the arc is stable, the electrode retains a (tailed end during welding, and has current-carrying capacity of thoriated electrodes. Zirconiated electrodes resist contamination and minimize tungsten contamination of weld metal. Duty-Cycle RatingPower-supply rating depends on the type and thickness of the workpiece and the length of time it takes to deposit the longest weld on the thickest material. Duty cycle is the key factor to consider when selecting a power source. Once the engineer has determined the current and voltage needed to accomplish the weld, he then reviews duty cycle requirements.Duty cycle rating is the percentage of time during a 10-minute period a power aircompressorreceivertanls supply can operate at rated output amperage without overheating. A 300 A machine at 60-percent-duty cycle can weld for six minutes at 300. A during a 10-minute period. Alter six minutes, the welder must rest the machine for the next four aircompressorreceivertanls minutes to avoid overheating the unit. Searching for accessories for your air compressor? We offer the best selection of cheap air compressor accessories on the internet. Check out our website for great deales on all of our air compressor accessories!
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