Welding Guidelines
General
This welding machine 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 6.
Slag | Wire |
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| Flux |
Weld |
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| Work |
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Crater
Figure 6 - Weld Components
NOTE: Discontinue using and discard electrodes that burn down to 1 to 2 inches from the electrode holder.
STRIKING AN ARC
Attach work clamp to work piece. The jaws of the work clamp must make good contact with clean bare metal of the work piece for good welding results.
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 ensure 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 in. off the surface or it will stick (See Figure 7).
Same as Electrode Diameter
Figure 7 - Scratching Method
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.
ELECTRODE TYPE AND SIZE
Two types of electrodes are recommended for this welder. The electrodes are commonly known by the AWS (American Welding Society) designation as follows:
1 .
•All position, smooth deposit rod with low spatter.
•For all mild steel and general purpose work .
2 .
•Smooth bead and fast deposition
•Ideal for joints with poor fitup and general repair work
NOTE:
Model WS0970 and WS0990
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 selecting the appropriate high or low setting. The amperage required depends on the size (diameter) of electrode used and the thickness of the work piece.
Excessive currents burn through light metals and the weld bead is flat and porous (See Figure 9). The bead appears high and irregular if the current 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 8).
5o - 45o
Travel Angle
Work Angle
Figure 8 - Weld Angle
Travel angle is the angle in the line of welding and may vary from 5º to 45º from the vertical, depending on welding conditions.
Work angle is the angle from horizontal, measured at right angles to the line of welding.
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