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 whichthe base metals are heated tofusion or melting temperatureby an electric arc.
•Arc is created between acovered metal electrode andthe base metals
•Base metals, arc, electrode,and weld are shielded fromthe atmosphere while welding.
•Shielding Gas: used to protectthe weld area from theatmosphere. Not pressurized.
•As flux melts, creates theshielding gas.
SMAW
DC vs. AC
•DC
•Flows in one direction
•DCEP creates deeperpenetration then DCEN
•DCEN caused electrode tomelt faster and deposit fillermetal at a faster rate.
•DCEN heats the base moreslowly then DCEP
•More versatile becausepolarity can be changed
•AC
•60 cycles per second
•Cycle= repeating events
•One direction 1/120 of a secthen reverses for 1/120 of asec
•Medium depth ofpenetration.
•Meet most weldingrequirements, 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 removedafter each arc weldbead or pass iscompleted.
•Slag is the hard, brittlematerial that covers afinished SMAW.
•Use a Chipping hammerto chip slag away. Thenfurther clean with awire brush.
Electrode Identification
•First two (sometimes three)numbers from the left =minimum tensile strength.
•Last numeral = polarity
•Second number from theright = recommendedwelding position/ type ofweld.
–1- all positions.
–2- flat welding and horizontalfillet welds
–3- flat position only
–4- flat, horizontal, overhead,or vertical down welding
