AN6226-02 Buna-N 70 U-Cup Seal 3/16" ID X 9/16" OD X 3/16" CS

Get consistent sealing and smooth operation in compact systems with the AN6226-02 U-Cup Seal. Designed for hydraulic and pneumatic applications, this seal helps prevent leaks, reduce downtime, and keep your equipment performing the way it should.

Manufactured from black Buna-N (NBR) at 70 durometer, this U-Cup provides excellent oil resistance and flexibility. It is a dependable, cost-effective choice for customers who need reliable sealing in small diameter applications.

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

Material & Performance Details

This seal is made from Buna-N (Nitrile, NBR), a proven material widely used in fluid power systems. With a 70 durometer hardness, it delivers a strong balance of flexibility and durability for dynamic sealing.

U-Cup seals energize under pressure and do not rely heavily on 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 weather 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): 3/16" (0.187" | 4.75 mm)
• Outside Diameter (OD): 9/16" (0.562" | 14.29 mm)
• Part Number: AN6226-02
• Cross References:
  • Parker Hannifin: 42956226-02
  • Hercules: 870-02
  • Martin Fluid Power: 6226-02
  • Precision Associates: 6226-2

Dimensions: 3/16" ID X 9/16" OD X 3/16" CS
Actual: 0.187" ID X 0.562" OD X 0.187" CS
Metric: 4.75 mm ID X 14.29 mm OD X 4.75 mm CS

Applications & Use Cases

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

Rated for pressures up to 500 PSI, it is a solid solution for both OEM builds and maintenance repairs.

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 seal. You get accuracy, speed, and support that helps you avoid costly mistakes.

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

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

FAQs

1. What does AN6226 mean?
AN6226 is an Army-Navy standard that defines U-Cup seal dimensions and ensures interchangeability.

2. Is Buna-N suitable for hydraulic systems?
Yes. Buna-N is highly resistant to petroleum-based oils and hydraulic fluids.

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