Chemraz 615 vs Perlast G75B: FFKM Compound Comparison
Verified by Rachel Mayfield, Supply Chain Analyst - April 2026
Chemraz 615 and Perlast G75B are both perfluoroelastomer (FFKM) compounds used in chemical, refinery, and process applications. Chemraz 615 vs Perlast G75B 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 | Perlast G75B |
|---|---|---|
| Manufacturer | Greene Tweed | Precision Polymer Engineering |
| Compound | 615 | G75B |
| Maximum continuous temp | 324°C | 327°C |
| Minimum temp | -10°C | 0°C |
| Hardness | 75 Shore A | 75 Shore A |
| Colour | Black | Black |
| Typical applications | Refinery, chemical, hot amines, steam | Chemical process, pharma, refinery, food (G75H FDA variant) |
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 Perlast G75B
Perlast G75B suits chemical process and similar service. Continuous temperature window is 0°C to 327°C, hardness 75 Shore A. Manufactured by Precision Polymer Engineering.
Key differences
- Temperature ceiling: Perlast G75B runs 3°C hotter (327°C vs 324°C). Specify the higher-rated compound when continuous service is above 324°C.
- Hardness: Both are 75 Shore A, so groove design and squeeze percentage are interchangeable.
- Manufacturer: Chemraz 615 is from Greene Tweed; Perlast G75B is from Precision Polymer Engineering. 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 Perlast G75B?
Yes, Chemraz 615 and Perlast G75B 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 Perlast G75B?
Perlast G75B has a higher continuous temperature ceiling (327°C vs 324°C, a 3°C difference).
Which costs less: Chemraz 615 or Perlast G75B?
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 Perlast G75B 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.