AN6226-41 Buna-N 70 U-Cup Seal 1/8" ID X 3/8" OD X 1/8" CS

Get a compact, precision seal that delivers reliable performance in tight spaces. The AN6226-41 U-Cup Seal is designed to prevent leaks, reduce downtime, and keep small hydraulic and pneumatic systems running smoothly.

Manufactured from black Buna-N (NBR) at 70 durometer, this U-Cup provides excellent oil resistance and flexibility. The smaller 1/8" cross section makes it ideal for precision applications where space is limited but performance still matters.

Operating temperature: -40° to +225°F (–40° to +107°C)

Material & Performance Details

This seal is made from Buna-N (Nitrile, NBR), a widely trusted sealing material for fluid power applications. The 70 durometer hardness provides a balanced combination of flexibility and durability.

The AN6226 design features a square-style cross section where the nominal cross section equals the height, ensuring consistent sealing performance even in compact designs.

Excellent resistance to:

• Petroleum-based oils and fuels
• Hydraulic fluids
• Mineral oils and greases
• Water (short-term exposure)

Limited capability with:

• Mild acids and bases
• Ozone and outdoor exposure

Not compatible with:

• Strong acids
• Brake fluids (glycol-based)
• Aromatic hydrocarbons

Sizes & Measurements

• Cross Section (CS): 1/8" (0.125" | 3.18 mm)
• Inside Diameter (ID): 1/8" (0.125" | 3.18 mm)
• Outside Diameter (OD): 3/8" (0.375" | 9.53 mm)
• Part Number: AN6226-41
• Cross References:
  • Parker Hannifin: 42956226-41
  • Hercules: 870-41
  • Martin Fluid Power: 6226-41
  • Precision Associates: 6226-41

Dimensions: 1/8" ID X 3/8" OD X 1/8" CS
Actual: 0.125" ID X 0.375" OD X 0.125" CS
Metric: 3.18 mm ID X 9.53 mm OD X 3.18 mm CS

Applications & Use Cases

This AN6226 Series U-Cup is commonly used in small hydraulic cylinders, pneumatic systems, valves, and compact fluid control applications. It is ideal where low friction, precision fit, and consistent sealing are required in tight spaces.

With a pressure rating up to 500 PSI, it is well suited for both OEM equipment and maintenance applications.

Key Specifications

• Material: Buna-N (NBR)
• Durometer: 70 Shore A
• Color: Black
• Specification: AN6226 (Army-Navy Standard)
• Temperature Range: -40°F to +225°F (-40°C to +107°C)
• Pressure Rating: Up to 500 PSI

Why Buy from The O-Ring Store LLC

When you order from us, you are getting more than just a seal. You are getting accuracy, speed, and support that helps you avoid mistakes and downtime.

• ISO9001:2015 certified quality processes
• USA stock for fast delivery
• Same-day shipping on in-stock items
• Custom sizes available when standard sizes do not fit
• Full lot traceability and documentation available
• Technical support from experienced staff
• Competitive pricing without sacrificing quality

We make getting O-Rings easy and help you get it right the first time.

FAQs

1. What makes this size different from larger U-Cups?
The smaller cross section is designed for compact applications where space is limited but reliable sealing is still required.

2. Is Buna-N suitable for oil applications?
Yes. Buna-N provides excellent resistance to petroleum-based oils and hydraulic fluids.

3. What pressure can this seal handle?
This U-Cup is rated for applications up to 500 PSI.