Positional Welding and Qualification Tests
Plate positions 1G-4G, overhead challenges, weld reinforcement, and CWB qualification testing.
- Identify plate welding positions 1G through 4G and their requirements
- Describe overhead welding challenges and adaptations
- Explain CWB qualification test procedures and acceptance criteria
Leçon 1
Plate Welding Positions 1G Through 4G
Position Definitions
Welding positions are standardized designations that describe the orientation of the weld joint relative to horizontal. "G" stands for groove weld on plate.
Fillet Weld Positions
Fillet welds use "F" designations:
- 1F - flat fillet
- 2F - horizontal fillet
- 3F - vertical fillet
- 4F - overhead fillet
Difficulty Progression
Each position presents increasing challenges:
| Position | Difficulty | Key Challenge |
|---|---|---|
| 1G/1F (Flat) | Easiest | Gravity helps maintain weld pool |
| 2G/2F (Horizontal) | Moderate | Gravity pulls weld pool down on groove face |
| 3G/3F (Vertical) | Difficult | Gravity pulls weld pool down continuously |
| 4G/4F (Overhead) | Most difficult | Gravity pulls weld pool away from joint |
Qualification Hierarchy - Common Exam Trap
4G (overhead) does NOT qualify for 3G (vertical). They are separate qualifications with different techniques. Know the exact hierarchy per CSA W47.1:25.
Positional Qualification Hierarchy (CSA W47.1:25)
The qualification hierarchy per CSA W47.1:25 is specific - overhead and vertical are not interchangeable:
3G Qualification
Qualifies for: 1G + 2G + 3G
Technique: gravitational shelf-building (vertical uphill)
Puddle supported on previously deposited weld
Does NOT qualify for 4G
4G Qualification
Qualifies for: 1G + 2G + 4G
Technique: perpendicular dropout control
Puddle must be held against gravity
Does NOT qualify for 3G
The reason vertical and overhead are separate: they require fundamentally different puddle manipulation techniques. In 3G (vertical), the welder builds a shelf of solidified weld metal to support the advancing puddle (gravitational shelf-building). In 4G (overhead), the welder must actively counteract perpendicular dropout - the weld pool wants to fall away from the joint entirely. These techniques do not transfer between positions.
To qualify for all four positions, a welder must test in both 3G and 4G (or test in positions that together cover all four).
Welding positions progress from 1G (flat, easiest) to 4G (overhead, hardest). Per CSA W47.1:25, the hierarchy is: 3G qualifies for 1G, 2G, and 3G; 4G qualifies for 1G, 2G, and 4G. Vertical and overhead require different puddle control techniques and do not cross-qualify for each other. Fillet (F) and groove (G) qualifications are separate.