X-Ring 66.04x5.33 NBR Quad Ring Nitrile Rubber Seal

What Is the X-Ring 66.04x5.33 NBR?

The X-Ring 66.04x5.33 NBR is a precision-engineered four-lip sealing ring, also known as a Quad Ring, manufactured from NBR (Nitrile Butadiene Rubber, Buna-N). Unlike a conventional O-ring, the X-shaped profile creates four sealing contact points, improving sealing efficiency while reducing friction and minimizing seal twisting during dynamic operation. With an inside diameter of 66.04 mm and a 5.33 mm cross section, this sealing ring is widely used in hydraulic systems, pneumatic equipment, pumps, valves and industrial machinery requiring reliable long-term sealing performance. The dimensions correspond to AS568-334.

Why Choose an X-Ring Instead of an O-Ring?

The unique Quad Ring profile offers several performance advantages over traditional O-rings.

Key benefits include:

• Four sealing contact points
• Lower operating friction
• Reduced seal wear
• Excellent resistance to spiral twisting
• Improved lubricant retention
• Better groove stability
• Enhanced dynamic sealing performance
• Longer service life in many moving applications

These advantages make X-Rings particularly suitable for demanding dynamic sealing systems.

Technical Specification

Material: NBR (Nitrile Butadiene Rubber, Buna-N)

Seal Type: X-Ring (Quad Ring)

Hardness: 70 Shore A

Inside Diameter: 66.04 mm

Cross Section: 5.33 mm

Profile: Four-Lip

Colour: Black

Dimensional Standard: AS568-334

Chemical Resistance: Mineral oils, lubricating greases and many petroleum-based industrial fluids

How Does an X-Ring Work?

The X-shaped cross section creates four independent sealing edges instead of the two sealing points found on a conventional O-ring.

This design provides:

• Improved sealing efficiency
• Reduced friction
• Better lubrication retention
• Lower heat generation
• Reduced risk of seal twisting
• Longer service life of both the seal and mating components

The lower contact area also contributes to smoother movement in dynamic sealing applications.

Typical Applications

The X-Ring 66.04x5.33 NBR is commonly used in:

• Hydraulic systems
• Pneumatic systems
• Pumps
• Valves
• Hydraulic cylinders
• Pneumatic actuators
• Gearboxes
• Industrial machinery
• Industrial automation
• OEM manufacturing
• Industrial MRO maintenance

Its four-lip profile makes it especially suitable for applications involving reciprocating or rotary motion.

How to Select the Correct X-Ring

When selecting an X-Ring, engineers should consider:

• Inside diameter
• Cross-section diameter
• Seal material
• Operating medium
• Operating temperature
• Working pressure
• Type of movement
• Groove design

For dynamic applications, lubrication conditions and operating speed should also be evaluated.

OEM Manufacturing and Industrial Maintenance

NBR Quad Rings are widely used in OEM production and industrial maintenance because they provide improved sealing performance in demanding operating conditions.

They help:

• Reduce leakage
• Lower friction
• Extend seal life
• Improve machine reliability
• Reduce maintenance downtime
• Increase service intervals

These benefits make X-Rings an effective solution for modern industrial sealing systems.

Why Engineers Choose NBR X-Rings

• Four-lip sealing profile
• Lower friction than conventional O-rings
• Excellent groove stability
• High resistance to mineral oils and greases
• Reduced twisting during operation
• Extended service life
• Suitable for OEM manufacturing
• Proven solution for hydraulic and pneumatic equipment

Frequently Asked Questions (FAQ)

What is the difference between an X-Ring and an O-Ring?

An X-Ring has four sealing lips, providing lower friction, improved sealing performance and greater resistance to twisting compared with a standard O-ring.

What does the size 66.04x5.33 mm mean?

It specifies an inside diameter of 66.04 mm and a cross-section diameter of 5.33 mm. This size corresponds to AS568-334.

Is NBR resistant to mineral oils?

Yes. NBR provides excellent resistance to mineral oils, lubricating greases and many petroleum-based industrial fluids.

Where are X-Rings commonly used?

They are widely installed in hydraulic systems, pneumatic equipment, pumps, valves, cylinders, gearboxes, industrial machinery and OEM equipment.

Are X-Rings suitable for dynamic applications?

Yes. Their four-lip profile is specifically designed to reduce friction, minimize twisting and improve sealing performance in dynamic applications.

Why choose an X-Ring instead of a standard O-Ring?

In many moving applications, X-Rings provide better sealing efficiency, lower friction, improved lubricant retention and a longer operating life than conventional O-rings.