5 Must-Have Features in a NBR Rubber OIL SEAL

Author: Geoff

May. 05, 2025

NBR O-Rings: Everything You Need to Know - Apple Rubber Products

NBR, also known as Nitrile or Buna-N, is one of the most widely used and economical elastomers. This material offers excellent sealing capabilities at a very low cost. NBR is a copolymer of butadiene and acrylonitrile, and depending on the application, the proportions of acrylonitrile can vary from 14% to 50%. The higher acrylonitrile content, the greater resistance to oil and fuel. 

Link to NNK

NBR Formulation

When formulating NBR compounds, filler, plasticizer, antioxidant or antiozonant, zinc oxide, accelerator, and vulcanizing agents may be used to increase specific sealing properties of the material. When it comes to filler, carbon black is typically used in standard NBR compounds. Altering the amount of carbon black will change the hardness of the final compound. 

Plasticizers increase the processability and modify physical properties of the final compound. Some of the modifications include lower hardness, improved flexibility, and low temperature performance. Sulfur is commonly used as a curing agent for NBR compounds. For sulfur cure systems, vulcanizing agents and accelerators are used to speed up the reaction rate between NBR and sulfur. 

Properties and Advantages

NBR is an ASTM D designation. These standard compounds have a working temperature range of -40°F to 257°F and hardness range of 40 to 90 Shore A. NBR compounds can be formulated to offer additional temperature ranges from -85°F to 275°F.

NBR features excellent resistance and mechanical properties, including: 

  • Resistance to petroleum-based oils and fuels, silicone greases, hydraulic fluids, water and alcohols
  • Low compression set
  • High tensile strength
  • High abrasion resistance
  • Low gas permeability

While NBR offers great resistance to many chemicals and solutions, there are some limitations to be aware of. NBR should have limited contact with:

  • Ozone, sun exposure, rain, wind
  • Highly aromatic fuels
  • Non-polar solvents
  • Glycol-based brake fluids

Typical Applications

Because of NBR’s compatibility with oils and fuels, NBR seals are commonly used in the automotive industry. However, NBR is a go-to material for oil applications of any kind. NBR is also commonly used in applications such as:

  • Low temperature military applications
  • Off-roading equipment
  • Marine devices
  • Aircraft fuel systems

NBR can also be formulated to meet FDA standards, which increases the number of ways to apply NBR o-rings.

Want more information on NBR Rubber OIL SEAL? Feel free to contact us.

Want to learn more about NBR o-rings?

Contact an engineer today. 

General Properties, Features and Applications of Nitrile Rubber

General Properties, Features and Applications of Nitrile Rubber

Jan 02, Rubber Seals | Oil Seals | Material

Nitrile Butadiene Rubber or NBR is a popular elastomer that is produced from a copolymer of acrylonitrile and butadiene. This versatile rubber material, owing to its several superior features and properties, is widely used in a number of applications across industries. It is one of the very sought after sealing materials due to its capability to resist oil, fuel, grease, water, air and flame retardant liquids (HFA, HFB, HFC). There are several things you must know about this synthetic rubber, and this is what exactly is covered in this post.

General Properties of Nitrile Rubber

The physical and chemical properties of NBR vary in part with the polymer’s composition of nitrile. However, the material exhibits the following properties in general.

  • Hardness: 85 +/- 5 shore
  • Modulus 100%: Greater than or Equal to psi
  • Tensile strength: Greater than or Equal to psi
  • Elongation at break: Greater than or Equal to 150%
  • Tear Strength: Greater than or Equal to 102 lbf/inch
  • Specific Gravity: 1.28 g/cm3
  • Rebound Elasticity: Greater than or Equal to 20%
  • Abrasion: 100 mm3
  • Compression Set: Less than or Equal to 5%
  • Compression Set: Less than or Equal to 6%
  • Service Temperature: -22 deg. F
  • Service Temperature: 230 deg. F
  • Low-Temperature Range: 70º F to 0º F
  • Minimum for Continuous Use (Static): 40º F
  • Brittle Point: 70° F to 0º F
  • Maximum for Continuous Use (Static): + 250º F

Why Choose Nitrile Rubber Seals

The seals manufactured from NBR or Buna-N are the best option for applications involving highly polar solvents such as acetone, MEK, ozone, chlorinated hydrocarbons, and nitro hydrocarbons. What else add to the popularity of Nitrile Rubber seals, here they are listed;

Nitrile Rubber Seals possesses:

  • Excellent abrasion resistance
  • Good rebound, tear resistance, and non-polar solvent resistance
  • Good water and oil resistance.
  • Good resistance to gas permeability
  • Good elongation properties and excellent compression set resistance
  • Adequate resilience and tensile strength
  • Good resistance to aliphatic hydrocarbons
  • Excellent adhesion to metal and rigid materials
  • Excellent colorability

Applications of Nitrile butadiene Rubber Seals

Due to its ability to be compounded with several other materials, Nitrile Butadiene Rubber is chosen for numerous applications, and the most important amongst them is as the sealing material. The material is used to make food grade seals, water-cut seals, oil seals, O-rings, and other industrial seals. Due to its strong resistance to heat aging and several other features listed above, Nitrile Rubber Seals are widely chosen for endless applications across industries including:

  • Automotive
  • Nuclear
  • Power generation
  • Food processing
  • Medical
  • Aerospace

Rather than using as a sealing material, Nitrile butadiene Rubber goes into the manufacturing of:

  • Roll covers
  • Hydraulic Hoses
  • Conveyor Belting
  • Graphic arts
  • Oilfield packers
  • Plumbing materials
  • Injection or transfer molded products
  • Extruded hose or tubing
  • Floor mats and industrial belting
  • Various sponge articles


Would you like to have seals made from this durable Nitrile Rubber for your applications? Consider sourcing the seals made from Nitrile Butadiene Rubber or NBR from trusted manufacturers who possess in-depth knowledge about sealing materials. SSP Manufacturing Inc. is one such leading names that provide NBR seals in standard and metric sizes to meet the requirements of industries. The company combines nitrile rubber with PVC to produce seals that offer better resistance to aging, flame, petrol, and ozone. These nitrile rubber seals also offer low-temperature flexibility and resilience when compared to other competitor products.

The company is the world’s best gearbox oil seal factory supplier. We are your one-stop shop for all needs. Our staff are highly-specialized and will help you find the product you need.

Related Post

  • How to Choose the Right Gasket Material for a Non-Metallic Gasket
  • What are the Most Commonly Used Materials in Sanitary Gaskets?
  • 6 Reasons that Explain Why Silicone Seals are used in Food Service Equipment

0

0

Comments

Please Join Us to post.

0/2000

All Comments ( 0 )

Guest Posts

If you are interested in sending in a Guest Blogger Submission,welcome to write for us!

Your Name: (required)

Your Email: (required)

Subject:

Your Message: (required)