Sour fluid resistant elastomers
Natural gas and crude oil containing high concentrations of hydrogen sulfide/sulphide (H2S) are known as sour fluids. H2S is highly corrosive, flammable and toxic, and can have detrimental effects to elastomers. Non-resistant elastomers can swell, blister or become hard and brittle, losing their elastic properties, all of which can ultimately lead to seal failure.
PPE has developed a range of sour fluid resistant elastomer materials for the oil, gas and petrochemical processing industries with third party test certification to various industry standard and some bespoke sour fluid test regimes. PPE’s EnDura®, Perlast® and Perlast® ICE materials offer a wide selection of sour gas resistant elastomers.
PPE has elastomers that have been tested to the following industry standards:
· ISO 23936-2 / NORSOK M710 Rev 3 Annex A
· ISO 10423 (API 6A) Section F.1.13.5.2
High concentration H2S testing
Going a step further than conventional tests, PPE has undertaken material testing at elevated temperatures and sour gas concentrations of 25% which exceed the minimum requirements of the ‘standard’ 2% NORSOK test. These higher test parameters are more representative of real-life service conditions and seek to find the limits of the elastomer’s capability and give the design engineer a level of comfort for the design limits in a given sealing application.
PPE materials tested to sour fluid standards
| PPE grade | Material type | Description | ISO 10423 (API 6A) | ISO 23639-2 | NACE TM0187 | NORSOK M710 2% H2S | NORSOK M710 25% H2S |
| EnDura® A90H | FEPM | Aflas® based copolymer | Fail*† | Fail*† | Not tested | Fail*† | Tested† |
| EnDura® V91A | FKM | Ultra-low temp grade | Pass | Pass | Pass | Pass | Tested† |
| EnDura® Z95X | HNBR | General purpose grade | Pass | Pass | Pass | Pass | Not tested |
| Perlast® G92E | FFKM | Chemical resistant grade | Pass | Pass | Not tested | Pass | Tested† |
| Perlast® G90LT | FFKM | Chemical resistant low temp grade | Pass | Pass | Not tested | Pass | Tested† |
†Contact PPE for further details.
Visit the Resources section to view/download material datasheets and test certification.
Sour gas test parameters for elastomers
| ISO 10423 (API 6A) | ISO 23936-2 | NACE TM0187 | NORSOK M710 2% H2S (Rev.2) | NORSOK M710 25% H2S | |
| Test vessel composition: Gas phase Oil phase Water phase | 35% 60% 15% | 30% 60% 10% | 90% 5% 5% | 30% 60% 10% | 30% 60% 10% |
| Gas phase composition: Volume (%) | 10% H2S 80% CO2 10% CH4 | 2% H2S 3% CO2 95% CH4 | FKM | HNBR 20% H2S | 5% H2S 5% CO2 | 20% CO2 75% CH4 | 75% CH4 | 2% H2S 3% CO2 95% CH4 | 25% H2S 3% CO2 72% CH4 |
| Oil phase composition: Volume (%) | 100% kerosene | 10% toluene 20% cyclohexane 70% heptane | 5% toulene 20% octane 25% hexane 50% decane | 10% toluene 20% cyclohexane 70% heptane | 10% toluene 20% cyclohexane 70% heptane |
| Water phase composition: Volume (%) | 100% deionised water | 100% distilled water | 100% ASTM S1193 Type IV | 100% distilled water | 100% distilled water |
| Test specimen location | Oil phase | Oil phase | Gas phase | Oil phase | Oil phase |
| Temperature | 177°C | Various from 100 to 200°C | 150°C FKM 100°C HNBR | Various from 100 to 200°C | Various from 150 to 175°C |
| Test duration | 160 hours | 8 weeks | 160 hours | 8 weeks | 8 weeks |
Resources
Below are some of our most popular downloads on sour gas sealing.
If you require further information on any sealing topic, please check out the Resources section of this website.
- Brochure: Sour gas resistant elastomers
- Certificates: Sour gas testing
- Datasheets: Sour gas resistant elastomers
- Webinar: Sealing with elastomers in sour gas
