What causes porosity during welding?
In any welding process, porosity can be caused by the presence of contaminants or moisture in the welding zone, which includes the base metal, filler metal, shielding gas, and the surrounding atmosphere. Contaminants can include oil, dirt, grease, or cutting fluids. Concurrently, moisture can collect in the flux, shielding gas, or on the base metal, or come from the atmosphere. Porosity occurring in a welding process that utilizes an external shielding gas can occur from using too much or too little gas flow, poor gas quality, or a defective welding torch, gun, or hose. Operator technique can also cause porosity. Electrode, torch, or gun angle can lead to porosity, as can excessive arc length, electrode extension, or travel speeds. Q: How can I obtain NDE certification? A: The certification of personnel performing nondestructive inspection can be accomplished by the following methods: 1) Obtain certification through training and testing by the American Society of Nondestructive Testing
