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SMAW. Shielded Metal Arc Welding. Technical Terms . AC Chipping Hammer CC CV DC DCEN DCEP DCRP DCSP Electrode holder SMAW. SMAW. Is a welding process in which the base metals are heated to fusion or melting temperature by an electric arc.
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SMAW Shielded Metal Arc Welding
Technical Terms • AC • Chipping Hammer • CC • CV • DC • DCEN • DCEP • DCRP • DCSP • Electrode holder • SMAW
SMAW • Is a welding process in which the base metals are heated to fusion or melting temperature by an electric arc. • Arc is created between a covered metal electrode and the base metals • Base metals, arc, electrode, and weld are shielded from the atmosphere while welding. • Shielding Gas: used to protect the weld area from the atmosphere. Not pressurized. • As flux melts, creates the shielding gas.
DC vs. AC • DC • Flows in one direction • DCEP creates deeper penetration then DCEN • DCEN caused electrode to melt faster and deposit filler metal at a faster rate. • DCEN heats the base more slowly then DCEP • More versatile because polarity can be changed • AC • 60 cycles per second • Cycle= repeating events • One direction 1/120 of a sec then reverses for 1/120 of a sec • Medium depth of penetration. • Meet most welding requirements, easy to use, cost less, used in industry, farm, and in home shop
SMAW Machines • Produce either CC or CV • SMAW require a CC
Chipping Hammer/ Wire Brush • Slag must be removed after each arc weld bead or pass is completed. • Slag is the hard, brittle material that covers a finished SMAW. • Use a Chipping hammer to chip slag away. Then further clean with a wire brush.
Electrode Identification • First two (sometimes three) numbers from the left = minimum tensile strength. • Last numeral = polarity • Second number from the right = recommended welding position/ type of weld. • 1- all positions. • 2- flat welding and horizontal fillet welds • 3- flat position only • 4- flat, horizontal, overhead, or vertical down welding