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2-008 Buna-N 70 O-Rings - Green


Quantity Discount Prices
Min:  2084
  • Model: B70008-GRN
  • 0 in Stock
  • 3/16"ID X 5/16"OD X 1/16"CS
  • Actual: 0.176"ID X 0.070"CS
  • Metric: 4.47mm ID X 1.78mm CS
  • PDF Data Sheets

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

Green O-Rings Buna-N - Nitrile (NBR) Duro 70:

Nitrile, also known as Buna-N or NBR, is a copolymer of Butadiene and Acrylonitirle. It is the most commonly used elastomer for sealing products. It has a temperature range of -40F to +250F and is exceptionally resistant to petroleum base oils and hydrocarbon fuels. Nitrile materials also exhibit excellent tensile strength and abrasion resistance properties. The material performs well with most dilute acids, silicone oils and lubricants and in water applications. It is not recommended for use with ketones, aromatic hydrocarbons and phosphate ester hydraulic fluids. More than 50% of the Orings sold are Buna-N Orings, commonly used in hydraulic/pneumatic motors, cylinders, pumps and valves.

Buna-N / Nitrile Recommended uses:

  • General purpose sealing.
  • Petroleum oils and fluids.
  • Gasoline
  • Hydraulic fluids
  • L.P. gases
  • Cold Water.
  • Silicone greases and oils
  • Di-ester base lubricants (MIL-L-7808).
  • Ethylene glycol base fluids (Hydrolubes)

Nitrile is not recommended for:

  • Halogenated hydrocarbons (carbon tetrachloride, trichloroethylene)
  • Nitro hydrocarbons (nitrobenzene, aniline)
  • Phosphate ester hydraulic fluids (Skydrol, Fyrquel, Pydraul).
  • Ketones (MEK, acetone)
  • Ozone
  • Sunlight, UV
  • Weather
  • Strong Acids Ozone
  • Automotive brake fluid

Operating temperature: -40° to +250F°

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Stock O-Rings in over 20 different compounds and durometers the following six are the standard rubber materials in a range of durometers (Shore A) hardness to satisfy practically any service condition:

Viton® O-Rings / FKM: Fluorocarbon (Viton®) exhibits exceptional resistance to chemicals, oils, temperature extremes (-13°F to +446°F), low compression set, low gas permeability and excellent aging characteristics. Applications include: aircraft engines, automotive fuel handling systems, and chemical processing industries. FKM is also suitable for high vacuum applications. It is not recommended for exposure to ketones, alkalis, and Skydrol® fluids. Custom compounds are available with improved chemical and low temperature resistance.
AS-568 Viton® O-Rings | Metric Viton® O-Rings

Buna-N O-Rings / Nitrile O-Rings / NBR: Nitrile (Buna-N) is the most widely used elastomer due to its excellent resistance to petroleum products, operating temperature range (-40°F to +257°F) and one of the best performance-to-cost values. It's an ideal material for aerospace, automotive, propane and natural gas applications. Special Hydrogenated Nitrile (HNBR) compounds can improve resistance to direct ozone, sunlight, and weather exposure while increasing temperature range to +300°F.
AS-568 Buna-N O-Rings | Metric Buna-N O-Rings

Ethylene-Propylene / EPDM O-Rings: EPDM has outstanding resistance to heat, water and steam, alkali, mild acidic and oxygenated solvents, ozone, and sunlight (-40ºF to +275ºF); but it is not recommended for gasoline, petroleum oil and grease, and hydrocarbon environments. This popular rubber compound is usually the first choice for low torque drive belt applications.
AS-568 EPDM O-Rings | Metric EPDM O-Rings

Fluorosilicone O-Rings / FVMQ: Fluorosilicone (-75º to +400ºF) combines the good high and low temperature stability of silicones with the fuel, oil, and solvent resistance of fluorocarbons. FVMQ is unparalleled for aerospace fuel systems, auto fuel emission control systems and to meet or exceed government, military, aerospace, automotive, industrial and commercial specifications. However, due to relatively low tear strength, high friction and limited abrasion resistance of these materials, they are generally not used in dynamic applications. They are also not recommended for exposure to brake fluids, hydrazine, or ketones.
AS-568 Fluorosilicone O-Rings | Metric Fluorosilicone O-Rings

Silicone O-Rings / VMQ: In the Silicone family, you will find compounds which are superior as static seals in extreme temperature conditions. Standard compounds handle operating temperatures -85º to +400ºF. Silicone compounds are popular in food and medical applications because they are very clean and do not impart odor or taste. Special Phenyl silicones can be used down to -148°F.
AS-568 Silicone O-Rings | Metric Silicone O-Rings

Neoprene® O-Rings / CR: Neoprene (-40º to +250ºF) is reasonably priced and features good resistance to petroleum oils, ozone, sunlight and oxygen aging, relatively low compression set, good resilience and outstanding physical toughness. It is the preferred sealing material for the refrigeration industry because of its resistance to ammonia and Freon®.
AS-568 Neoprene® O-Rings