Operating Instructions and Parts Manual

WS4369 and WS4469

 

 

Welding Guidelines

General

This line of welding machines utilizes a process known as Shielded Metal-Arc Welding (SMAW). This process is used to bond metals by heating them with an electric arc created between the electrode and the work piece.

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 5.

Wire

Flux

Weld

Slag

Crater

Figure 5

 

Work Piece

 

Note: Discontinue using and discard electrodes that burn down to 1 to 2 inches from the electrode holder.

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.

There are two methods which can be used to start or strike the arc; the tapping method and the scratching method. In the tapping method, the electrode is brought straight down and tapped on the work piece. With the scratching method, drag the electrode at an angle along the surface much like striking a match. Regardless of method, upon contact with the plate, immediately raise the electrode a distance equal to the diameter of the electrode or it will stick to the surface. Always hold the electrode pointed into the weld (See Figure 6).

Same as electrode diameter

Same as electrode diameter

Figure 6

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.

ARC Welding Basics

Five basic techniques affect weld quality. These are: electrode selection, current setting, weld angle, arc length, and travel speed. Proper implementation of these techniques is necessary for good weld quality.

Electrode Type and Size

The correct choice of electrode type involves a variety of factors, such as welding position, work piece material type, thickness, and condition of surface to be welded. The American Welding Society, AWS, has set up certain requirements for each type of electrode.

All electrodes are classified into five main groups: mild steel, high-carbon steel, special alloy steel, cast iron, and nonferrous such as aluminum. The majority of arc welding is done with the electrodes in the mild steel group. The electrode material should corres- pond with the work piece material.

Flux coatings are made for use with either AC (alternating current), DC (direct current) reverse polarity, or DC straight polarity, although some function well on both AC and DC current.

AWS Electrode Classification

E - 6 0 1 3

E = Electrode

60 = Mild steel

70 = High strength Steel

1= Electrode can be used in all positions

2= Electrode is restricted for use in flat or horizontal position only

Flux type

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