Weld porosity is an common issue that is found in most welding process. Many processes have the same issues, but FCAW has a unique set of causes and solutions for weld porosity. Porosity in FCAW is caused by the same issues as in other types of welding, but the most common types of porosity are very unique to this type of welding. The three main causes of weld porosity for FCAW are:
Windy or drafty conditions
Moisture from an improperly stored electrode
Electrode stick-out
Windy or drafty conditions are the most common cause of
butt fusion welding machine manufacturers porosity. This is true for just about any welding process out there. Once the shielding is lost, even if only for a brief moment, the weld joint gets exposed to the air and then you have those tiny holes that make the weld look like a sponge. FCAW is a process that does well in windy conditions, however when using dual shielding electrodes, there is the gas shielding that can be easily blown away by drafts and wind. The simplest solution is finding a way to keep any drafts from coming into the weld area. This can be as simple as using your body or hands as shields, or as complex as building barriers to ensure there are no drafts coming through the weld area. In some cases, when using a dual shield electrode it might be a good idea to increase the gas flow rate. Higher gas flow rates can be a good way to compensate for losing shielding gas, but they can also be a cause of weld porosity. The more gas that flows through the nozzle, the higher the chances are that turbulence is going to effect the shielding gas flow. Turbulence will cause the shielding gas to mix in with the air around it and become another cause of weld porosity because of oxygen in the air.
