Selecting the proper elastomer for wellhead seals such as packings, O-rings, or stripper rubbers is fundamental for durable and safe sealing. The table below is a helpful guide for the selection of wellhead elastomers but should not be used without a thorough understanding of elastomer properties and wellhead conditions.
| Component | Compound | Typical Durometer Hardness |
Max H2S |
Max CO2 |
Max Service Temp. (H2S & CO2) (F/C) |
Steam Service |
Max Service Temp (Sweet) (F/C) |
| Seal | Nitrile (BUNA) | 55-75 | 2% | NR | 150/65 | NR | 250/121 |
| Seal | HNBR | 65 | 10% | 20% | 225/107 | NR | 325/163 |
| Seal | Fluoroelastomer (Viton) | 80 | 20% | 5% | 200/93 | R | 400/204 |
| Q/O Ring | Nitrile (BUNA) | 90 | 5% | NR | 150/65 | NR | 250/121 |
| Q/O Ring | Viton | 75 | 20% | 5% | 200/93 | R | 400/204 |
| Q/O Ring | Tetrafluoroethylene-propylene (AFLAS) |
80 | 35% | 15% | 300/149 | HR | 450/232 |
NR - Not recommended
R - Recommended
HR - Highly recommended