Oil Resistant Nitrile O-Rings with 70-90 Shore A Hardness and Custom Sizes for

Product Specification

Product Overview

High-Performance Nitrile (NBR) O-Rings | 70-90 Shore A

Our Buna-N (NBR) O-rings are the most widely specified sealing solution for industrial applications worldwide. Known for their exceptional balance of mechanical toughness and cost-effectiveness, these multi-purpose rubber seals provide reliable leak prevention across a vast range of environments.

Whether you are performing routine maintenance (MRO) or designing new industrial machinery, our Nitrile O-rings deliver the durability required for consistent performance.

The Advantages of Nitrile (NBR/Buna-N) Material

Nitrile Butadiene Rubber, commonly known as NBR or Buna-N, is the most widely used elastomer in the seal industry. Its popularity stems from a unique set of characteristics that make it ideal for hydraulic applications:

• Exceptional Oil Resistance: NBR is specifically designed to resist petroleum-based oils, fuels, and greases, making it the standard choice for hydraulic systems.

• High Tensile Strength: It offers excellent mechanical properties, including high resistance to tearing and abrasion.

• Compression Set Resistance: NBR maintains its shape and sealing force over long periods of operation.

• Versatility and Value: It provides high-performance sealing at a lower cost compared to exotic fluorinated elastomers.

Multi-Purpose Applications

Our Versatile Nitrile Seals are used across virtually every industry, including:

• General Machinery: Gearboxes, pumps, compressors, and conveyors.
• Pneumatic Systems: Air cylinders, valves, and pneumatic tools.
• Fluid Power: Standard hydraulic connections and fluid transfer components.
• MRO Supply: Essential for repair kits in manufacturing plants and automotive workshops.
• Plumbing & HVAC: Reliable sealing for water systems and refrigeration units.

Material Comparison: NBR vs. Others

NBR vs. FKM (Fluorocarbon):
FKM is known for its ability to handle much higher temperatures (up to 200 degrees Celsius) and more aggressive chemicals. However, NBR is significantly more affordable and offers better flexibility and sealing performance at lower temperatures (down to -40 degrees Celsius), where FKM can become brittle.

NBR vs. EPDM (Ethylene Propylene):
EPDM is excellent for weather, ozone, and water resistance. However, EPDM will swell and fail almost immediately if it comes into contact with petroleum-based oils. NBR is the necessary choice whenever oil or grease is present in the system.

Product Description

	Material: Nitrile Butadiene Rubber (NBR / Buna-N)
	Color: Black
	Hardness: Typically 70 Shore A (Standard) - 90 Shore A (High Pressure)
	Tensile Strength: 14 to 18 MPa

Company Profile

Established in 2013, Shanghai Qinuo Industry (SHQN) specializes in the engineering and manufacturing of high-performance rubber seals for the Oil & Gas industry.

Our production base in Nantong is equipped with over 30 advanced vulcanizing machines, delivering a monthly capacity of 20 tons (40,000 lbs) across 20+ product categories. Strategically located near Shanghai’s major air and sea ports, we ensure streamlined logistics and reliable global delivery.

Under our registered brands Royal Way® and SHQN®, we remain committed to our core principle: "Quality for Stability, Innovation for Progress." We provide the energy sector with durable, precision-engineered sealing solutions you can depend on.

FAQ

Q: Is there a difference between Buna-N and Nitrile?
A: No, they are the same material. Buna-N is a trade name often used in North America, while **Nitrile (or NBR) is the common technical name. Both refer to Nitrile Butadiene Rubber.

Q: Can I order custom sizes for non-standard equipment?
A:Absolutely. While we carry a massive inventory of standard AS568 and Metric sizes, we specialize in OEM/ODM custom sizes. We can manufacture O-rings with custom internal diameters (ID) and cross-sections (CS) to fit your specific groove design without expensive tooling costs.

Q: What is the benefit of 70 Shore A vs. 90 Shore A for general use?
A: 70 Shore A is the "standard" hardness—it’s flexible and easy to install, making it great for lower pressure or static seals. 90 Shore A is much stiffer; it is chosen for high-pressure applications where the seal must resist being pushed (extruded) into the gap between metal surfaces.

Q: Where should I NOT use Buna-N O-rings?
A: Buna-N is not recommended for applications involving Ozone, UV light, or high-temperature steam. It also has poor resistance to brake fluids (glycol-based), ketones (MEK), and strong acids. For those environments, we recommend EPDM or FKM.