Which SMAW electrode must be kept in an electrode oven to keep the flux coating moisture low?

• A. E6010
• B. E6011
• C. E7014
• D. E7018

Answer: (D)

The concept here is that moisture in the flux coating of SMAW electrodes can introduce hydrogen into the weld, which risks hydrogen-induced cracking. Low-hydrogen electrodes are specifically dried to remove this moisture before use. The electrode that must be kept in an electrode oven to keep the flux coating moisture low is the low-hydrogen type with a basic flux. It is baked at about 350°F (177°C) for a couple of hours to drive out moisture, and then kept in a heated storage or in a dry, controlled environment to prevent reabsorption. If this drying step isn’t done, the moisture released during welding can increase hydrogen in the weld metal, leading to porosity and cracking, especially on thicker or higher-strength joints. The other electrodes listed use flux coatings that are either less moisture-sensitive or do not require the same baking routine, so they don’t need to be kept in an electrode oven for moisture control.