6226-04 EPDM 70 U-Cup Seal 5/16" ID x 11/16" OD x 3/16" CS

This 70 durometer black EPDM U-Cup is peroxide cured for improved durability and compression set resistance. It is a strong choice for applications exposed to water, steam, and chemical environments where petroleum-based materials fail. You get longer service life and fewer maintenance interruptions." CS

If you need a dependable seal that handles pressure, water, and aggressive chemicals without breaking down, this AN6226 EPDM U-Cup is built for it. It delivers consistent sealing performance, helps prevent leaks, and reduces downtime in systems where reliability matters.

Operating temperature: -40° to +300°F (–40° to +149°C)

This EPDM compound stays flexible in cold environments while maintaining sealing strength at elevated temperatures.

Material & Performance Details

Manufactured from high-strength 70 durometer EPDM rubber, this U-Cup is engineered for long-lasting performance in harsh environments.

Performance strengths include:

• Excellent resistance to water and steam
• Strong resistance to polar chemicals
• Reliable sealing up to 500 PSI
• Good compression set resistance for extended service life
• Excellent weathering and ozone resistance

Chemical compatibility:

Excellent resistance to:

• Water and steam
• Phosphate esters
• Ketones
• Alcohols
• Alkalis
• Anhydrous ammonia

Limited capability with:

• Mild acids depending on concentration and exposure

Not compatible with:

• Petroleum oils and fuels
• Concentrated sulfuric acid
• Concentrated nitric acid

Sizes & Measurements

• Cross Section (CS): 4.76 mm (0.187 in)
• Inside Diameter (ID): 7.94 mm (0.312 in)
• Outside Diameter (OD): 17.46 mm (0.688 in)
• Part Number: 6226-04
• Standard: AN6226 Series

Applications & Use Cases

This U-Cup is commonly used in hydraulic and pneumatic systems where water, steam, or chemical resistance is required. It performs well in cylinders, valves, pumps, and fluid systems exposed to demanding conditions.

Typical industries include:

• Water treatment and processing
• Chemical handling systems
• Industrial equipment
• Air and gas systems
• Applications using phosphate ester fluids

If your system operates in wet or chemically aggressive environments, this seal helps maintain performance and reduce failures.

Key Specifications

• Material: EPDM (Peroxide Cured)
• Durometer: 70 Shore A
• Color: Black
• Standard: AN6226
• Certifications: UL approved per JOHX2 (water, steam, air, inert gases)
• Temperature Range: -40°F to +300°F (-40°C to +149°C)
• Pressure Rating: Up to 500 PSI

Why Buy from The O-Ring Store LLC

You want the right seal, on time, with no surprises. That is how we operate.

• ISO9001:2015 certified processes ensure consistency and traceability
• USA stock for fast, reliable delivery
• Same-day shipping on in-stock items
• Custom sizes available for unique applications
• Full lot traceability and documentation on request
• Experienced team that understands sealing applications
• Competitive pricing without sacrificing quality

We focus on helping you reduce downtime and keep your operation running smoothly.