Wire Feed Arc Welder
Welding Guidelines (Continued)
work piece material thickness all affect the speed of travel necessary for completing a good weld (See Fig. 11). When the speed is too fast, the bead is narrow and bead ripples are pointed as shown. When the speed is too slow, the weld metal piles up and the bead is high and wide. For aluminum, travel speed is typically faster.
SLAG REMOVAL (FLUX-CORE WIRE ONLY)
Wear ANSI approved safety
glasses (ANSI Standard Z87.1) and protective clothing when removing slag. Hot, flying debris can cause personal injury to anyone in the area.
After completing the weld, wait for the welded sections to cool. A protective coating called slag now covers the weld bead which prevents contaminants in the air from reacting with the molten metal. Once the weld cools to the point that it is no longer glowing red, the slag can be removed. Removal is done with a chipping hammer. Lightly tap the slag with the hammer and break it loose from the weld bead. The final
NOTE: When making multiple weld passes, remove the slag before each pass.
WELDING POSITIONS
Four basic welding positions can be used; flat, horizontal, vertical, and
overhead. Welding in the flat position is easier than any of the others because welding speed can be increased, the molten metal has less tendency to run, better penetration can be achieved, and the work is less fatiguing. Welding is performed with the wire at a 45º travel angle and 45º work angle.
Other positions require different techniques such as a weaving pass, circular pass, and jogging. A higher skill level is required to complete these welds.
Overhead welding is the least desirable position as it is the most difficult and dangerous. Heat setting and wire selection will vary depending upon the position.
All work should be performed in the flat position if possible. For specific applications, consult an arc welding technical manual.
WELD PASSES
Sometimes more then one pass is necessary to fill the joint. The root pass is first, followed by filler passes and the cover pass. If the pieces are thick, it may be necessary to bevel the edges that are joined at a 60º angle.
NOTE: Remember to remove the slag before each pass for gasless process.
Cover
Filler
Root
Figure 12 - Weld Passes
Figure 13 - Multiple Weld Passes
Base Metal
Normal Heat, Wire Speed, Travel Speed
Heat Too Low
Heat Too High
Figure 11 - Weld Appearance
Travel Speed Too Fast
Travel Speed Too Slow
Wire Speed Too Slow
Wire Speed Too Fast
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