 Welding Torches and GunsUsed for shielded-metal-arc welding, torches (electrode holders). manually controlled, grip ends of electrodes, also called rods-pinch type and collet type are common.GMAW and FCAW guns come in pistol grip, goose-neck, and inline styles, the latter used for mechanized welding. Knowing the wire diameter, select a gun rated slightly higher than airranks the welding current to be used. Duty-cycle ratings airranks are usually given for C[O.sub.2] shielding--air or C[O.sub.2] cooling arc usually sufficient for welding at up to 600 A at less than 100 percent duty. Higher amperages require water cooling--high-amperage guns come with tubing for water cooling. Hand-held, mounted on a robot arm or fixed within a mechanized welding setup, guns guide filler wire and shielding gas into the weld puddle. High-deposition electrodes. These contain iron-powder additions in the coating to raise deposition rate. Designations: EXXX4, EXXX7, EXXX8.For fastest deposition, use the largest diameter possible for an application-the thicker the electrode, the greater its current-carrying capacity and the higher the deposition rate. Welding out of position and overhead, select a small diameter electrode to enable welders to reach into narrow root openings.Gas-Metal-Arc Welding (GMAW, MIG)GMAW typically uses solid wire, spooled or reeled, for continuous feeding to the gun; diameter, 0.030 to 1/16 in. typically, although wires as small as 0.020 in. and as large as 1/8 in. are sometimes used. AWS lists specifications for filler wires of copper and airranks its alloys, aluminum and its alloys, surfacing alloys, airranks nickel and its alloys, titanium and its alloys, carbon and low alloy steels, magnesium alloys, and zirconium and its alloys. For AC-GTAW of Aluminum Alloys,... most of the significant advances focus on new ways to manipulate the AC wave form. These advances largely result from using inverter-based power sources, which allow a welder to extend the balance control, adjusting airranks output frequency and independently controlling current in each AC halt cycle. New inverter-based GTAW machines extend EN balance control, allowing duration airranks from 50 to 90 percent. Making the EN portion of the cycle last longer:* Allows greater weld penetration* May permit increasing travel speeds by as much as 20 percent.* Narrows the weld bead* May permit using a smaller-diameter tungsten electrode to more precisely direct the heat or deposit a narrower weld bead 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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