Electrode

From GAWDAwiki

Various shielded metal arc welding electrodes with an electrode holder

An electrode is a conductor, not necessarily metallic, through which a current enters or leaves a nonmetallic medium, such as an electrolytic cell, arc generator, vacuum tube or gaseous discharge tube.^[1]

In arc welding, an electrode is used to conduct current through a workpiece to fuse two pieces together. Depending upon the process, the electrode is either consumable, (as in gas metal arc welding and shielded metal arc welding), or non-consumable, as in TIG welding. An electrode in an electrochemical cell becomes either an anode or a cathode depending on the voltage applied to the cell. A bipolar electrode functions as the anode of one cell and the cathode of another cell.^[2]

Types of Electrodes

Different types of electrodes include:

Metal-Arc. Filler metal in the form of a wire or rod, whether bare or covered, through which current is conducted between the electrode holder and the arc.
Carbon-Arc. A carbon or graphite rod through which current is conducted between the electrode holder and the arc.
Atomic Hydrogen. One of the two tungsten rods between the points of which the arc is maintained.
Electrolytic Oxygen-Hydrogen Generation. The conductors by which current enters and leaves the water, which is decomposed by the passage of the current.
Resistance Welding. The part or parts of a resistance welding machine through which the welding current and the pressure are applied directly to the work.^[3]

Electrode Size and Amps Used

The following is a recommended guide for ampage and electrode size. These ratings may vary based on the manufacturer of the electrode. It is always best to check the manufacturer's information on a particular electrode.

Electrode Diameter	Amp Range	Plate
1/16 inch	20-40	Up to 3/16"
3/32 inch	40-125	Up to 1/4"
1/8 inch	75-185	Over 1/8"
5/32 inch	105-250	Over 1/4"
3/16 inch	140-305	Over 3/8"
1/4 inch	210-430	Over 3/8"
5/16 inch	275-450	Over 1/2"