AN6226-01 Buna-N 70 U-Cup Seal 1/8" ID X 1/2" OD X 3/16" CS

Get a tight, reliable seal in small bore applications without fighting installation or startup friction. The AN6226-01 U-Cup Seal is built for consistent sealing, helping you prevent leaks, reduce downtime, and keep your equipment running smoothly.

Manufactured from black Buna-N (NBR) at 70 durometer, this seal provides excellent oil resistance and flexibility. It is a strong choice for compact hydraulic and pneumatic systems where precision and repeatable performance matter.

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

Material & Performance Details

This U-Cup is made from Buna-N (Nitrile, NBR), a proven material widely used in fluid power applications. The 70 durometer hardness gives you a balanced seal that is flexible enough to energize properly while maintaining durability.

U-Cup seals are designed to seal with minimal initial compression, making them ideal for low breakaway pressure and smooth cycling.

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): 3/16" (0.187" | 4.75 mm)
• Inside Diameter (ID): 1/8" (0.125" | 3.18 mm)
• Outside Diameter (OD): 1/2" (0.500" | 12.70 mm)
• Part Number: AN6226-01
• Cross References:
  • Parker Hannifin: 42956226-01
  • Hercules: 870-01
  • Martin Fluid Power: 6226-01
  • Precision Associates: 6226-1

Dimensions: 1/8" ID X 1/2" OD X 3/16" CS
Actual: 0.125" ID X 0.500" OD X 0.187" CS
Metric: 3.18 mm ID X 12.70 mm OD X 4.75 mm CS

Applications & Use Cases

This AN6226 Series U-Cup is commonly used in small hydraulic cylinders, pneumatic tools, valves, and compact sealing environments. It performs well where low friction, reliable sealing, and consistent performance are required.

With a pressure rating up to 500 PSI, it is a dependable option for both OEM 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 get more than just a part number. You get consistency, speed, and confidence that the seal will fit and perform.

• 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 compromising quality

We focus on helping you get the right seal the first time so you avoid rework and downtime.

FAQs

1. What does AN6226 mean?
AN6226 is an Army-Navy specification that standardizes U-Cup seal sizes and performance for interchangeability.

2. Is Buna-N suitable for hydraulic systems?
Yes. Buna-N provides excellent resistance to petroleum-based oils and hydraulic fluids, making it a top choice.

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