Shielded Metal Arc Welding (SMAW)
1. Introduction
In this lab, you will gain knowledge of the Shielded Metal Arc Welding process by observing and
examining the effects of changes to welding current, arc length, uphill and downhill welding
directions, welding positions, welding electrode types and welding current types.
2. Equipments and Materials
• Lincoln 275 Precision TIG machine
• 1
/ 4 " x 6" and 1/ 4 " x 1" mild steel barstocks.
• E4313 (E6013), E4924 (E7024), E4311 (E6011) and E4918 (E7018) electrodes.
3. Experimental Procedure
Effects of Welding Current
• Using 1/ 8 "∅ E4313 (E6013) electrode with approximately 110 amps AC current, perform
single pass stringer bead on plate. Try to obtain a consistent ¼” wide weld bead.
• Turn the amperage up to 130A and make some additional beads.
• Turn the amperage down to 90A and make some additional beads.
Results and Discussion: what changes in weld quality and/or shape are noticed with different welding
currents?
Effects of Arc Length
• With 1/ 8 "∅ E4313 (E6013) electrode and approximately 110 amps AC current, attempt to
produce weld beads at a short arc length, then a long arc length.
• Record the voltage and amperage from the machine meters as you weld at these different arc
lengths.
Results and Discussion: How do these arc length changes affect the weld quality and bead shape?
Uphill vs. Downhill Welding Directions
• Using a pre-tack welded assembly, make T-joint fillet welds in the horizontal fillet (2F)
position.
• Place the workpiece at a 450 incline by supporting one end with some scrap steel. Make some
beads in a downhill direction with 1/ 8 "∅ E4313 (E6013) electrode at 110 amps AC current.
• Repeat the above step in an uphill direction.
1|Page
Results and Discussion: What effects do these welding directions have on the shape of the weld bead?
Which welding direction is easy in term of welding?
Effects of Welding Positions
2F Position
• Using / 8 " ∅ E4924 (E7024) electrode, make single pass fillet
1
3
welds in the 2F (i.e., horizontal) position. Then, produce a 1 2
larger weld size by depositing a 2nd and 3rd beads over the 1st
bead as shown. For this electrode, try a 200 pushing angle.
• Support your workpiece in the 1F (flat position) and make 2 pass fillet 1F Position
weld as shown using a weave on the 2nd pass. During weaving on the 2nd
2
pass, stay longer on the sides and move quickly across the center of the 1
weld bead.
Results and Discussion: What differences in weld bead and the ease of welding do you observe in
trying to obtain the larger weld sizes in the 1F vs. 2F positions?
Effects of Welding Electrodes
• Make several single pass fillet welds with a 1/ 8 " ∅ E4311 (E6011) electrode @ 105 amps AC.
Results and Discussion: How is this electrode compared to the E4924 (E7024) from a usability and
bead appearance standpoints? What are some other considerations in selecting which electrodes to
use?
Effects of Welding Current Types
• Using an E4918 (E7018) electrode @ 130 amps Direct Current Electrode Positive (DCEP),
make several single pass fillet welds.
• Switch to Direct Current Electrode Negative (DCEN) and make note of the differences in arc
stability and weld appearance. Please double check the welding current when switching the
current type.
• Switch to AC current.
Results and Discussion: Was there any difference in bead appearance or arc stability for DCEP vs.
DCEN vs. AC welding current types?
2|Page
