Operating Instructions and Parts Manual
Welding Guidelines
GENERAL
This line of welding machines utilizes a process known as Shielded
Electrodes used for shielded metal arc welding have two parts. The inner core is a metal rod or wire that should be similar in composition to the base metal. The outer coating is called flux. Various types of flux exist. Each coating is used for a particular welding situation.
While the metal is molten, it can be contaminated by elements in the air. This contamination could weaken the weld. The flux coating creates a protective barrier called slag that protects the molten metal from contaminants.
When current (amperage) flows through the circuit to the electrode, an arc is formed between the end of the electrode and the work piece. The arc melts the electrode and the work piece. The melted metal of the electrode flows into the molten crater and forms a bond with the work piece as shown in Figure 4.
NOTE: Discontinue using and discard electrodes that burn down to 1 to 2 inches from the electrode holder.
| Wire |
| Flux |
Weld | Slag |
| Crater |
| Work Piece |
Figure 4 - Weld Components | |
STRIKING AN ARC
Place the bare end of the electrode in the holder. Grip the holder lightly to reduce tiring of the hand and arm.
NOTE: Always keep the jaws of the holder clean to insure good electrical contact with the electrode.
Be careful not to touch the work piece
or welding bench with the electrode as this causes arc flashes.
The best method of striking an arc is the scratching method. Drag the electrode at an angle along the surface much like striking a match. Upon contact with the plate, lift the electrode approximately 1/16” off the surface or it will stick (See Figure 5).
NOTE: Should the electrode stick to the work piece, break it loose by quickly twisting or bending at the holder while pulling upward. If the electrode does not break loose, disengage the electrode by releasing it from the holder.
1/16 inch |
Same as Electrode Diameter |
Figure 5 - Scratching Method |
ELECTRODE TYPE AND SIZE
Four types of electrodes are recommended for this welder. The electrodes are commonly known by the AWS (American Welding Society) designation as follows:
1.
•Flat bead with deep penetrating arc.
•For rusted or dirty mild steel general repair work.
2.
•All position, smooth deposit rod with low spatter.
3.
•Smooth bead and fast deposition
•Ideal for joints with poor fitup and general repair work.
4.E-7018-AC High Strength
•Ideal for pipes and structural applications.
•Low hydrogen reduces porosity for a strong weld.
NOTE: Only the
ARC WELDING BASICS
Four basic techniques affect weld quality. These are: amperage setting, weld angle, arc length, and travel speed. Proper use of these techniques is necessary for good weld quality.
AMPERAGE SETTING
The correct amperage involves the adjustment of the welding machine to the required amp setting. This is regulated by a knob on the welder. The amperage required depends on the size (diameter) of electrode used and the thickness of the work piece.
Consult specifications listed on the welder. Excessive amps burn through light metals and the weld bead is flat and porous (See Figure 7). The bead appears high and irregular if the amperage is too low.
WELD ANGLE
Weld angle is the angle at which the electrode is held during the welding process. Using the correct angle ensures proper penetration and bead formation. Electrode angle involves two positions - travel angle and work angle (See Figure 6).
Travel angle is the angle in the line of welding and may vary from 5º to 45º from the vertical, depending on welding conditions.
• For all mild steel and general purpose work.
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