AN6226-18 Buna-N 70 U-Cup Seal 7/8" ID X 1-3/8" OD X 1/4" CS


Qty Discounts Prices
5-139
$0.710		 140-3,999
$0.355		 4,000-12,999
$0.248		 13,000+
$0.198

$0.710

  • Model: 6226-18
    Dimensions: 7/8" ID X 1-3/8" OD X 1/4" CS
    Actual: 0.875" ID X 1.375" OD X 0.250" CS
    Metric: 22.23 mm ID X 34.93 mm OD X 6.35 mm CS
  • 235 in Stock
Add to Cart:
Min Qty:  5

Get a stable, leak-free seal that keeps your system running efficiently. The AN6226-18 U-Cup Seal is designed to deliver consistent sealing performance, helping reduce downtime and maintain smooth operation in hydraulic and pneumatic systems.

Manufactured from black Buna-N (NBR) at 70 durometer, this U-Cup offers excellent oil resistance and durability. The 1/4" square profile provides added sealing stability, making it a reliable choice for demanding applications.

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 material in fluid power systems. The 70 durometer hardness provides a strong balance between flexibility and long service life.

The AN6226 design features a square-style cross section where the nominal cross section equals the height, improving sealing stability and consistent performance.

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): 1/4" (0.250" | 6.35 mm)
  • Inside Diameter (ID): 7/8" (0.875" | 22.23 mm)
  • Outside Diameter (OD): 1-3/8" (1.375" | 34.93 mm)
  • Part Number: AN6226-18
  • Cross References:
    • Parker Hannifin: 42956226-18
    • Hercules: 870-18
    • Martin Fluid Power: 6226-18
    • Precision Associates: 6226-18

Dimensions: 7/8" ID X 1-3/8" OD X 1/4" CS
Actual: 0.875" ID X 1.375" OD X 0.250" CS
Metric: 22.23 mm ID X 34.93 mm OD X 6.35 mm CS

Applications & Use Cases

This AN6226 Series U-Cup is commonly used in hydraulic cylinders, pneumatic systems, pumps, and valves. It is ideal for applications that require reliable sealing with low friction and consistent performance.

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 downtime and rework.

  • 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 focus on helping you get the right seal the first time so your equipment keeps running.

FAQs

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

2. Is Buna-N suitable for hydraulic systems?
Yes. Buna-N offers 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.