AN6226-48 U-Cup Seal Buna-N NBR 70 870-48

5/8" ID X 1" OD X 3/16" CS

Reliable Hydraulic and Pneumatic Seal for Dynamic Applications

The AN6226-48 Buna-N NBR 70 U-Cup Seal from The O-Ring Store LLC is engineered for dependable sealing in hydraulic and pneumatic systems. Made from durable Buna-N (Nitrile Rubber) with a 70A durometer hardness, this U-cup offers excellent flexibility, oil resistance, and performance under dynamic conditions. Designed to prevent leakage, reduce maintenance downtime, and extend equipment life, it’s a trusted choice for both OEM and MRO users seeking long-lasting performance at an affordable price.

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

Material & Performance Details

Compound: Buna-N (Nitrile Rubber, NBR)
Durometer: 70A
Color: Black

Buna-N is a general-purpose compound offering a strong balance of strength, flexibility, and oil resistance, ideal for hydraulic applications.

Excellent resistance to:

• Petroleum-based oils and fuels
• Water and hydraulic fluids (non-phosphate esters)
• Grease and mineral oils

Limited capability with:

• Ozone and sunlight (UV exposure)
• Mild acids

Not compatible with:

• Brake fluids (glycol-based)
• Phosphate ester hydraulic fluids
• Polar solvents such as acetone or MEK

Sizes & Measurements

• Cross Section (CS): 0.187 (4.75 mm)
• Inside Diameter (ID): 0.625 in (15.88 mm)
• Outside Diameter (OD): 1.00 in (25.4 mm)
• Part Number: AN6226-48
• AS568 Dash Number: N/A (per AN6226 military standard)

Applications & Use Cases

Commonly used in:

• Hydraulic cylinders and pumps
• Aerospace and military systems (AN/MIL spec)
• Pneumatic actuators and controls
• Agricultural and industrial machinery
• Automotive and heavy equipment repairs

Key Specifications

• Material: Buna-N (Nitrile Rubber)
• Durometer: 70A
• Color: Black
• Standard: AN6226 / Military specification
• Temperature range: -40° to +225°F (–40° to +107°C)
• Pressure rating: Up to 500 psi dynamic (varies with application)

Why Buy from The O-Ring Store LLC

• ISO9001:2015 certified quality processes
• USA stock for fast delivery
• Same-day shipping on in-stock seals
• Custom sizes and materials available
• Full lot traceability and documentation upon request
• Expert technical support from experienced sealing specialists
• Competitive pricing without sacrificing performance

FAQs:

Q1: What does “AN6226-48” mean?
A1: It refers to a U-cup seal designed to meet the AN6226 military specification, with “48” designating the specific size.

Q2: Can this Buna-N seal be used with synthetic hydraulic fluids?
A2: Only with petroleum-based fluids; it’s not compatible with phosphate ester or glycol-based fluids.

Q3: What’s the difference between 70A and 90A durometer U-cups?
A3: 70A provides better flexibility and sealing for low-pressure systems, while 90A offers greater extrusion resistance for higher pressures.