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 Production vs. repair applications In general, production applications aircompeessorkits require high-duty-cycle power supplies, and repair applications can use low-duty-cycle portable units.Lift-arc GTAW Many DC power supplies are equipped with a list-start feature for, a variation of scratch starting, GTAW welding. When the welder touches the tungsten electrode to the workpiece, a small amount of current--15-20 A--flows. When he lifts the aircompeessorkits electrode from the work, the arc starts softly and the machine switches to the set weld-current value. This low-current starting minimizes weld contamination caused by touching the tungsten to the workpiece and eliminates the need for high-frequency starting. 1. Mechanical properties of the base material. Tensile strength and yield strength of the weld metal should aircompeessorkits equal or exceed that of the base material. Ductility and toughness at low temperatures may also be important. High-temperature service requires resistance aircompeessorkits to creep. Shock loading aircompeessorkits requires impact resistance. In general, weld metal should match base-material properties.2. Composition of the base material.For stainless steels, low alloy aircompeessorkits and aircompeessorkits steels, nickel and copper alloys, and materials that serve in corrosive atmospheres, chemical composition is important. Consider the possibility of electrochemical corrosion between base and weld metal of different compositions. Saw Uses CV or CC Power Supplies,... 200 to 1,500 A, 28 to 44 V, at 60- to 100-percent-duty cycle. Automatic units commonly use up to 1,500 A on one wire. Cv welding machines that offer variable-slope control give the welder extra adjustability, and can extend the usefulness of the machine to weld a range of material thicknesses and types.Selection of Power SourcesWhen choosing a power source, start by checking NEMA specs. NEMA Class I arc-welding power sources deliver rated output at 60-, 80-, or 100-percent-duty cycle: Class II units, 30-, 40-, or 50-percent; and Class III, 20 percent. First consider capacity and kind of current needed for the job. Rely on the manufacturer''s rating as being conservative: don''t buy more capacity than needed. Choose low--duty-cycle machines only for maintenance aircompeessorkits or for intermittent welding. aircompeessorkits If portability is important, consider inverter units. 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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