Diesel Exhaust Fluid (DEF) Systems: EPDM Resistance to Urea Solutions.
Diesel Exhaust Fluid (DEF) Systems: EPDM Resistance to Urea Solutions.
RubberQ Engineering

Diesel Exhaust Fluid (DEF) Systems: EPDM Resistance to Urea Solutions
Problem Statement
DEF systems require materials resistant to urea solutions, which cause chemical degradation in standard elastomers. Common failures include swelling, loss of sealing integrity, and compression set failure at elevated temperatures.
Material Science Analysis
EPDM (Ethylene Propylene Diene Monomer) excels in DEF systems due to its saturated hydrocarbon backbone. This structure resists urea-induced chemical attack. EPDM's ethylene content enhances chemical resistance, while its propylene content improves flexibility and low-temperature performance.
Technical Specs
- Shore A Hardness: 70 ± 5
- Tensile Strength: 12 MPa
- Elongation at Break: 300%
- Temperature Range: -40°C to 120°C
- Compression Set: 25% (22 hours at 100°C)
Material Comparison
| Material | EPDM | NBR | FKM |
|---|---|---|---|
| Chemical Resistance to Urea | Excellent | Poor | Good |
| Temperature Range (°C) | -40 to 120 | -20 to 100 | -20 to 200 |
| Compression Set (%) | 25 | 40 | 15 |
| Cost | Moderate | Low | High |
Standard Compliance
RubberQ adheres to IATF 16949 standards for batch-to-batch consistency. Our in-house compounding ensures precise control of polymer ratios, fillers, and curing agents. We comply with ASTM D2000 for material callouts and ISO 3601 for sealing performance.
For custom material compound development or IATF 16949 documentation, consult RubberQ's engineering department.
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