21 FCAW Techniques

Remember that specific FCAW procedures may vary depending on the welding position, material type, and joint configuration. It’s important to follow the manufacturer’s recommendations, welding codes, and industry standards when performing FCAW. Additionally, practice and experience play a significant role in mastering FCAW procedures and achieving high-quality welds.

Safety Precautions

• Wear appropriate personal protective equipment (PPE), including welding helmet, gloves, and clothing.
• Work in a well-ventilated area to avoid exposure to fumes and gases generated during welding.

FCAW electrode wires produces smoke and fumes. Some base metals can also produce toxic fumes when welded. Fume extraction equipment should be used to keep smoke and fumes from entering under the welder’s helmet and to protect others who are working in the area. Some options to deal with fumes include:

• A fume extractor with a flexible hose arm can be positioned close to the fume source.
• It is good safety practice to use a welding helmet equipped with a respirator to protect the face, eyes, nose, and lungs from smoke and fumes.
• Specially designed welding guns are available with built-in fume extraction systems to evacuate smoke and fumes from the weld area while providing maximum visibility.

Welding Parameters

• Voltage: Controls the length and stability of the arc. Adjust to control penetration and bead shape.
• Wire Feed Speed: Determines the amount of filler metal deposited. Adjust to achieve the desired weld size and bead appearance.
• Travel Speed: Affects the weld size and heat input. Faster travel speeds result in less heat input, while slower speeds provide more heat input.
• Polarity: Typically used in DC electrode positive (DCEP) for better penetration and reduced spatter.

Joint Preparation

• Clean and prepare the joint surfaces before welding to remove rust, paint, dirt, and contaminants.
• Proper joint geometry, including bevels or grooves, may be required for thicker materials to achieve proper penetration.

Welding Technique

• Maintain a consistent travel speed and arc length to produce even and smooth weld beads.
• Watch for proper fusion between the base metal and the filler metal.
• Use weaving or oscillation techniques for wider welds.
• A steady push or a Z-weave technique can be used for welding in the vertical position with uphill travel.
• When using the weave technique, move up the joint in small increments, and stop momentarily at each toe to prevent undercut.

Post-Welding Steps

• Inspect the weld for defects such as lack of fusion, porosity, and cracks.
• Clean the weld area to remove any slag or spatter.
• Depending on the application and material, consider performing post-weld heat treatment or stress relief to release residual stresses.