15 standard grades from NBR to FFKM
Four quantities matter for the selection: surface speed, pressure, temperature and the medium to be sealed. As the temperature rises, the interactions between medium and material speed up — which is why the choice of material is no side issue.
15 materials
| Code | Family | Hardness Shore A | Color | T min | T max | Characteristics |
|---|---|---|---|---|---|---|
| 1 | NBR | 74 | Black | -20 °C | 100 °C | Standard material. Resistant to mineral oils and their products, hydraulic oils, water glycols, oil-in-water emulsions, animal and vegetable oils, gasoline, heating oil and water up to about 70 °C. |
| 2 | FKM | 65 | Turquoise | -12 °C | 220 °C | Outstanding resistance to high temperatures, ozone, oxygen, mineral oils, synthetic hydraulic fluids, fuels, aromatics and many solvents. |
| 3 | EPDM | 73 | Blue | -40 °C | 150 °C | Very good resistance to aging, UV and ozone, and therefore also suitable outdoors. Resistant to dilute acids. Not resistant to mineral oil products. |
| 5 | HNBR | 70 | Brown | -40 °C | 150 °C | Suitable for higher pressures, not prone to explosive decompression. Resistance as NBR, plus PAO oils. |
| 6 | VMQ | 73 | Red-brown | -50 °C | 200 °C | Silicone for very low temperatures and hot air up to +210 °C. |
| 7 | FKM | 71 | Gray | -17 °C | 220 °C | Friction-optimized FKM grade with self-lubricating additives. |
| 8 | FKM | 73 | White | -17 °C | 220 °C | FKM with a PTFE content, friction-optimized. |
| 9 | FKM | 73 | Gray | -17 °C | 220 °C | FKM variant for increased demands. |
| 19 | FKM | 72 | Near-white | -17 °C | 220 °C | FKM-PTFE for food and hygiene applications. |
| 29 | FKM | 73 | Blue | -17 °C | 220 °C | FKM-PTFE for food applications, metal-detectable. |
| C2 | FKM | 78 | Anthracite | -17 °C | 220 °C | Special FKM grade, higher hardness. |
| C5 | HNBR | 75 | Anthracite | -25 °C | 150 °C | Special HNBR grade. |
| CP5 | HNBR | 80 | Black | -25 °C | 150 °C | HNBR High Performance, higher hardness for high pressures. |
| M5 | HNBR | 93 | Black | -40 °C | 150 °C | Very hard HNBR grade for extreme pressure loads. |
| 71 | FFKM | 75 | Black | -20 °C | 260 °C | Perfluoroelastomer — chemically resistant to almost everything, with the highest temperature resistance. |
Hardness figures with a tolerance of ±5 Shore A. The temperature limits apply to the material, not necessarily to the seal in a specific operating case — pressure, speed and medium shift them. If you cannot find the right grade here, talk to us.
For food, medical technology and regulated processes
FDA-compliant grades
FKM-PTFE food, FKM-FEP food, metal-detectable variants and food-grade FFKM. Plus a seal design with no cavities and no bonding agents, with a smooth transition to EHEDG and DIN EN 1672-2.
USP Class VI
Materials for CIP- and SIP-capable processes, temperature-resistant to 230 °C, designed with minimal dead volume.
PFAS-free and detectable
For applications in which freedom from PFAS is required, and for processes with metal detection in quality assurance.
What makes elastomers age
Visible changes
- Cracking
- The surface becoming tacky
Measurable changes
- Hardening or softening
- A drop in stress values
- A loss of elastic properties
Contact media
In use, seals come into contact with very different media: mineral oils, synthetic fluids, vegetable and animal oils, hydraulic and brake fluids, fuels, organic solvents, water and aqueous solutions, acids and bases, refrigerants, gases and vapors.
These media can penetrate the material and act on it both physically and chemically. Under their influence elastomers harden or soften — and the higher the temperature, the faster these processes run.
Worth singling out: HNBR is outstandingly suited to higher pressures and is not prone to explosive decompression. FKM with PTFE or self-lubricating additives is the choice when friction is to stay as low as possible.
Every design, material and size in one PDF
60 pages of design know-how: pressure and p-v diagrams, design guidelines, the elastomer overview and the complete size table with 541 sizes. You receive the link by e-mail straight away.
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