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-348 HNBR (HSN) Highly Saturated Nitrile 70 Duro O-Ring


Quantity Discount Prices

  • Model: H70348
  • 3 in Stock
  • 4-3/8"ID X 4-3/4"OD X 3/16"CS
  • Actual: 4.350"ID X 0.210"CS
  • Metric: 110.49mm ID X 5.33mm CS
  • PDF Data Sheets

4-3/8"ID X 4-3/4"OD X 3/16"CS

Highly Saturated Nitrile Butadiene Rubber

HNBR, or HSN, is a hydrogenated NBR for increased saturation of the butadiene segment of the main carbon polymer chain. This gives HNBR better thermal stability, greater tensile strength, greater wear and extrusion resistance, increased resistance to ozone and oxygen, and broader chemical resistance compared to a standard NBR. HNBR It is often seen in automotive air conditioning applications due to its excellent resistance to R-134a refrigerants. With minimal degredation, HNBR may be used from -40°F to 300°F  for extended periods.

HNBR / HSN Recommended uses:

  • Petroleum oils and fluids.
  • Automotive refrigerants (R134-a)
  • Hydrogen sulfide (H2S) or sour gas
  • Carbon Dioxide (CO2)
  • Gasoline
  • Hydraulic fluids
  • L.P. gases
  • Silicone greases and oils
  • Di-ester base lubricants (MIL-L-7808).
  • Ethylene glycol base fluids (Hydrolubes)

Not recommended for:

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

Compound Info:

  • Highly Saturated Nitrile Butadiene Rubber Peroxid Cured
  • Color: Green
  • Duro: 70
  • FDA: No
  • ASTM D2000 M4DH716 A26 B36 EO16 EO36 F17 Z1 Z2 (Z1=Green Color ,  Z2=Automotive A/C Refrigerant Resistance)

Operating temperature: -40° to +300°F

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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® / 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.

Buna-N / Nitrile / 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.

Ethylene-Propylene / EPDM: 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.

Fluorosilicone / 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.

Silicone / 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.

Neoprene® / 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®.