Precision Black Nitrile O-Rings Buna Seals for Hydraulic Systems

Product Overview

A rubber o ring is a vital sealing component used in virtually every hydraulic and pneumatic system worldwide. It is a loop of elastomer with a round cross-section, designed to be seated in a groove and compressed during assembly between two or more parts. This compression creates a physical barrier that prevents the leakage of fluids or gases.

Our Precision Black Nitrile O-Rings are engineered to provide a dependable, cost-effective, and long-lasting seal for industrial machinery, ensuring peak performance and preventing system downtime.

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.

Material Comparison: HNBR 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) or 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

Question: What is the typical shelf life of a Nitrile (NBR) O-ring?
Answer: When stored in a cool, dry place away from direct sunlight, UV light, and ozone-generating equipment (like electric motors), NBR O-rings have a shelf life of approximately 15 years.

Question: Can I use Nitrile O-rings for outdoor applications?
Answer: Standard NBR has moderate resistance to environmental factors. For prolonged outdoor use where exposure to sunlight and ozone is high, the material may develop surface cracks. In such cases, EPDM might be more appropriate.

Question: What is the difference between 70 Shore A and 90 Shore A hardness?
Answer: 70 Shore A is the standard flexibility for most hydraulic applications. 90 Shore A is significantly harder and stiffer, providing better resistance to extrusion in very high-pressure systems.

Question: Is it safe to reuse a Nitrile O-ring after a machine teardown?
Answer: It is not recommended. Once an O-ring has been compressed and exposed to heat and pressure, it takes a permanent set. Reusing it may lead to leaks because the seal cannot return to its original shape to provide a new compression.