Material compatibility and typical corrosion rates for various services.
| Service | Carbon Steel | SS 304/316 | Duplex SS | Special Alloys |
|---|---|---|---|---|
| Sweet Gas | Excellent | Excellent | Excellent | Not required |
| Sour Gas (H₂S<5%) | Good* | Excellent | Excellent | For severe service |
| Sour Gas (H₂S>5%) | Limited** | Good | Excellent | Recommended |
| CO₂ (dry) | Excellent | Excellent | Excellent | Not required |
| CO₂ (wet) | Poor | Good | Excellent | For severe service |
| Amine | Good*** | Excellent | Excellent | Not required |
| TEG | Excellent | Excellent | Excellent | Not required |
| Mercury | Good | Good | Good | Monel/Titanium |
* With appropriate H₂S limits per NACE MR0175
** Requires special metallurgy or inhibition
*** Stress relief required, velocity limits apply
| Environment | Carbon Steel | SS 316 | Duplex 2205 | Hastelloy C |
|---|---|---|---|---|
| Sweet gas (dry) | <1 | <0.1 | <0.1 | <0.1 |
| Sweet gas (wet) | 5-20 | <0.5 | <0.2 | <0.1 |
| Sour gas (dry) | 1-5 | <0.2 | <0.1 | <0.1 |
| Sour gas (wet) | 20-100+ | 1-5 | <0.5 | <0.2 |
| CO₂/water | 50-200+ | 1-10 | <1 | <0.5 |
| Lean amine | 5-20 | <1 | <0.5 | <0.2 |
| Rich amine | 20-50 | 1-5 | <1 | <0.5 |