Chemraz 615 vs Isolast J9504: FFKM Compound Comparison
Verified by Rachel Mayfield, Supply Chain Analyst - April 2026
Chemraz 615 and Isolast J9504 are both perfluoroelastomer (FFKM) compounds used in chemical, refinery, and process applications. Chemraz 615 vs Isolast J9504 They share similar chemistry but differ on temperature ceiling, hardness, and intended service. This page compares the two side-by-side and explains when to specify each.
Side-by-side comparison
| Property | Chemraz 615 | Isolast J9504 |
|---|---|---|
| Manufacturer | Greene Tweed | Trelleborg Sealing Solutions |
| Compound | 615 | J9504 |
| Maximum continuous temp | 324°C | 270°C |
| Minimum temp | -10°C | -10°C |
| Hardness | 75 Shore A | 75 Shore A |
| Colour | Black | Black |
| Typical applications | Refinery, chemical, hot amines, steam | Refinery, chemical, hot service |
When to specify Chemraz 615
Chemraz 615 suits refinery and similar service. Continuous temperature window is -10°C to 324°C, hardness 75 Shore A. Manufactured by Greene Tweed.
When to specify Isolast J9504
Isolast J9504 suits refinery and similar service. Continuous temperature window is -10°C to 270°C, hardness 75 Shore A. Manufactured by Trelleborg Sealing Solutions.
Key differences
- Temperature ceiling: Chemraz 615 runs 54°C hotter (324°C vs 270°C). Specify the higher-rated compound when continuous service is above 270°C.
- Hardness: Both are 75 Shore A, so groove design and squeeze percentage are interchangeable.
- Manufacturer: Chemraz 615 is from Greene Tweed; Isolast J9504 is from Trelleborg Sealing Solutions. Lead time and UK availability vary by brand.
- Cost: FFKM pricing varies by manufacturer, batch size, and stock position. Both compounds are at the premium end of elastomer pricing (£30 to £500+ per O-ring depending on size).
Get a UK quote on either compound
Related pages
Frequently Asked Questions
Can I substitute Chemraz 615 for Isolast J9504?
Yes, Chemraz 615 and Isolast J9504 are both FFKM compounds with overlapping chemical compatibility. Verify your specific fluid against both manufacturers' compatibility tables before substitution. Temperature window, hardness, and certifications may differ.
Which is hotter: Chemraz 615 or Isolast J9504?
Chemraz 615 has a higher continuous temperature ceiling (324°C vs 270°C, a 54°C difference).
Which costs less: Chemraz 615 or Isolast J9504?
FFKM compound pricing depends on manufacturer, batch size, certifications, and current stock position rather than headline brand. Both compounds are at the premium end of elastomer pricing. Get current UK quotes on both before specifying.
Where can I buy Chemraz 615 or Isolast J9504 in the UK?
Both compounds are supplied in the UK by independent FFKM seal specialists carrying multiple manufacturer lines. Lead time is typically 2-5 working days for stock BS 1806 / AS568 sizes, 4-8 weeks for custom-moulded sizes.