Understanding AWS Welding Electrode Classifications: Coating Types and Recommended Currents Explained

Type of Coating:

• Digit 0: Indicates a cellulose-based coating. For example, AWS classification E6010 is a cellulose-based electrode commonly used for root passes in pipeline welding due to its deep penetration capabilities.
• Digit 1: Denotes a rutile-based coating. For instance, AWS classification E7018 is a rutile-coated electrode widely used in structural welding applications for its smooth arc, low spatter, and high-quality welds.
• Digit 2: Represents a basic or low-hydrogen coating. An example is AWS classification E7018-1, which is a basic-coated electrode with improved toughness and resistance to hydrogen-induced cracking.
• Digit 3: Indicates an iron powder coating. AWS classification E7024 is an iron powder electrode known for its high deposition rates and suitability for welding thick sections in flat and horizontal positions.
• Digit 4: Denotes an iron oxide coating. For example, AWS classification E6011 is an iron oxide electrode commonly used for welding in all positions and for applications requiring good penetration and arc stability.
• Digit 5: Represents a low-alloy steel electrode with specific chemical composition requirements. An example is AWS classification E8018-B2, which is a low-alloy electrode suitable for welding high-strength steels.
• Digit 6: Indicates a high-alloy steel electrode with specific chemical composition requirements. An example is AWS classification E309MoL-16, which is a high-alloy electrode used for welding dissimilar metals and for applications requiring corrosion resistance.
• Digit 8: Denotes an electrode with a special coating or composition not covered by other digits. An example is AWS classification E316L-17, which is a special electrode suitable for welding low-carbon stainless steels and for applications requiring high resistance to corrosion and cracking.

Recommended Welding Current:

• Digits 0 and 1: These digits typically indicate electrodes that are suitable for use with alternating current (AC) or direct current electrode positive (DCEP). For example, E6011 and E6013 electrodes are commonly used with AC or DCEP for general-purpose welding applications.
• Digits 2 and 3: These digits often indicate electrodes that are suitable for use with direct current electrode negative (DCEN). For instance, E7018 electrodes are commonly used with DCEN for structural welding applications.