Resistance to Sour Gas Environments
Sour Gas Testing – NACE TM0177 Method A Tensile Test, Test Levels II and III, 720 hours, Applied Stress = 100% YS
Material
Condition |
Heat |
Yield Strength
(ksi) |
Coupled to
Carbon Steel |
Not Coupled to
Carbon Steel |
Cold-Worked |
Heat 1 |
205 |
Pass |
Pass |
Heat 2 |
191 |
Pass |
Pass |
Heat 3 |
204 |
Pass |
Pass |
Heat 4 |
233 |
Pass |
Pass |
Heat 5 |
225 |
Pass |
Pass |
Heat 6 |
223 |
Pass |
Pass |
Heat 7 |
215 |
Pass |
Pass |
Heat 8 |
222 |
Pass |
Pass |
*Triplicate tests
Sour Gas Testing – NACE TM0177 Method C, 90-Day C-Ring Test,
Test Level VII: 25% NaCl, 500 psi (3.5 MPa) H2S + 500 psi (3.5 MPa) CO2,
Elemental Sulfur = 1 g/l and 5 g/l**
Test Temperature: 401°F (205°C), Applied Stress = 100% YS
Material Condition: Cold-Worked
Heat |
Yield Strength
(ksi) |
Result* |
Heat 1 |
205 |
1 g/l S: Pass 5 g/l S: Pass |
Heat 2 |
187 |
1 g/l S: Pass 5 g/l S: Pass |
Heat 3 |
188 |
1 g/l S: Pass 5 g/l S: Pass |
*Triplicate tests
**With stirring
Sour Gas Testing – NACE TM0177 Method C, 90-Day C-Ring Test,
Test Level VII-Plus: 25% NaCl, 1000 psi (6.9 MPa) H2S + 1000 psi (6.9 MPa) CO2
Test Temperature: 401°F (205°C)
Material Condition: Cold-Worked
3 Passing Test Results |
Heat |
Yield Strength
(ksi) |
Heat 1 |
205 |
Heat 2 |
187 |
Heat 3 |
188 |
Heat 4 |
233 |
Heat 5 |
225 |
Heat 6 |
223 |
Heat 8 |
222 |
Sour Gas Testing – NACE TM0198 Slow Strain Rate Tensile Test, Test Level VII: 25% NaCl,
500 psi (3.5 MPa) H2S + 500 psi (3.5 MPa) CO2, Without (w/o) Elemental Sulfur
Test Temperature: 401°F (205°C)
Material Condition: Cold-Worked
Test Environment* |
Time to Failure (h) |
Elong. (%) |
R.A. (%) |
Time to Failure Ratio |
Elong. Ratio |
R.A. Ratio |
Secondary Cracking |
Air |
8.9 |
12.8 |
63.4 |
- |
- |
- |
- |
Level VII w/o S |
8.4 |
12.1 |
63.2 |
0.95 |
0.95 |
1 |
No |
*Air – single test; Level VII w/o S – triplicate tests
Sour Gas Testing – NACE TM0198 Slow Strain Rate Tensile Test, Test Level VII: 25% NaCl,
500 psi (3.5 MPa) H2S + 500 psi (3.5 MPa) CO2, With Elemental Sulfur
Test Temperature: 401°F (205°C)
Material Condition: Cold-Worked
Test Environment* |
Time to Failure (h) |
Elong. (%) |
R.A. (%) |
Time to Failure Ratio |
Elong. Ratio |
R.A. Ratio |
Secondary Cracking |
Air |
8.9 |
12.8 |
63.4 |
- |
- |
- |
- |
Level VII w/S |
8.2 |
11.7 |
62.4 |
0.92 |
0.91 |
0.98 |
No |
*Air – single test; Level VII w/S – triplicate tests