Wonder how to understand the Welding Electrode Classifications on Coating Penetration & Current Type? Different codes has different roles. Selecting the electrode is crucial to ease of cleanup, weld strength, bead quality, and minimizing any spatter. Here with a simplified version of guide to read and have a better understanding on the penetration depth and required current type.

Class E6013 are commonly used electrode on board. It is a general purpose for easy use.

E Indicates as an Electrode
60 Indicates how strong this electrode is when welded. 60,000 psi (per square inch) is the tensile in KSI, with a minimum tensile strength 62,000 psi and a minimum yield strength 50,000 psi
1 Indicates in what welding positions (flat, horizontal, vertical [up & down], overhead) it can be used
3 Indicates the Coating (Rutile, Potassium), Penetration (Light) and Current type (AC, DCEP, DCEN) used

Class E7018 produces high quality X-Ray welds.

E Indicates as an Electrode
70 Indicates how strong this electrode is when welded. The tensile in KSI with a minimum tensile strength 70,000 psi (per square inch) and a minimum yield strength 57,000 psi
1 Indicates in what welding positions (flat, horizontal, vertical [up & down], overhead) it can be used
8 Indicates the Coating (Low Hydrogen, Iron Powder), Penetration (Medium) and Current type (AC, DCEP) used.