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

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.