Chapter 8 Manual Welding Techniques
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5. Increase the amperage and form a weld pool
approximately 3/16″ (4.8 mm) in diameter.
6. Move the torch forward while:
A. Maintaining the weld pool size.
B. Maintaining the torch height.
C. Maintaining the torch angles.
7. Stop the weld at the end of the plate.
A. Do not lift the torch away from the plate.
Postfl ow gas will protect the hot metal during
the cooling period.
Problem Areas and Corrections
1. Uneven top weld width and depression.
Possible cause: Variation in welding speed.
Solution: Maintain a consistent travel speed.
Possible cause: Heat buildup in the weld pool.
Solution: Maintain travel speed to reduce heat.
2. Uneven contour.
Possible cause: Incorrect torch angle.
Solution: Align the torch vertically over the weld.
3. Uneven penetration or lack of penetration.
Possible cause: Insuffi cient amperage.
Solution: Increase amperage.
Possible cause: Variable torch height.
Solution: Keep the torch the same height above
the weld pool.
Possible cause: Variable travel speed.
Solution: Maintain a travel speed that keeps the
weld pool a consistent size.
Welding Procedure Number 8-2
Weld joint type: Bead on plate
Position: Flat
Material type: Cold-rolled steel
Thickness: 1/16″ (1.6 mm)
Filler metal: ER70S-2 or 6
Diameter: .045″ (1.1 mm)
Machine setup: DCEN high-frequency start
Shielding gas: Argon
CFH: 15–25
Tungsten type: 1%, 1.5%, or 2% lanthanated,
ceriated, or thoriated
Diameter: 1/16″ (1.6 mm) (tapered)
Procedure:
1. Prepare and clean the materials.
2. Raise the part to be welded 1/8″ (3.2 mm) above
the table with metal blocks.
3. Align the torch to the angles shown in Figure 8-13
and lower the torch until the electrode tip is
approximately 1/8″ (3.2 mm) from the top surface.
Figure 8-12.
Torch position for an autogenous weld in the
fl at position. (Mark Prosser)
Figure 8-13.
Torch and welding rod positions for running
a bead on a plate in the fl at position. (Mark Prosser)