O-RING MATERIALS

BUNA-N

Overview: Economical and versatile for use in a variety of application environments, Buna-N (Nitrile) is one of our most popular o-ring choices. 

Durometer (Hardness of O-ring) Availability:  50-70

Temperature Range: -35°F to 250°F

Works Well With:

• Silicone Greases/Oils
• Water
• Petroleum Oils/Fuels
• Ethylene Glycol Fluids

Available in:
Series 100 Cartridge Valves
Series 100 Specialty Valves
Series 200 NPT Valves
Series 300 Modular Valves
Series 500 Miniature Modular Valves

Mechanical Properties:
Buna-N has a “good” rating for wear resistance, compression set resistance, short-term resilience, and permeation resistance.  To compare mechanical properties of all o-rings, view the chart below.

Note: Great for gamma sterilization and/or autoclaving.

BACK TO TOP »

ETHYLENE-PROPYLENE (EPDM)

Overview: Another popular choice for o-rings, EPDM has the added bonus of being Class VI compatible, upon request.

Durometer (Hardness of O-ring) Availability:  50-70 (with 70 being the standard size)

Temperature Range: -60°F to 250°F

Works Well With:

• Sunlight / Ozone / Weathering
• Hot Water and Steam
• Auto/Aircraft Brake Fluids
• Keytones and Alcohols
• Certain Acids and Bases
• Plumbing

Available in:
Series 100 Cartridge Valves
Series 100 Specialty Valves
Series 200 NPT Valves
Series 300 Modular Valves
Series 500 Miniature Modular Valves

Mechanical Properties:
EPDM has a “good” rating for resistance and a “moderate” rating for short-term resilience. To compare mechanical properties of all o-rings, view the chart below.

Note: The compounds of EPDM o-rings at Class VI compatibility require that we use a higher durometer such as 60 or 70. Customers also have the option of peroxide or sulfur cured EPDM o-rings, depending on a particular application’s needs. However, if you are dealing with ozone, we always recommend peroxide cured to ensure the o-ring does not corrode.

BACK TO TOP »

VITON®

Overview: Compatibility with petroleum and fuel oils make Viton® (Flurocarbon Type A) a popular choice within the Automotive and Aerospace industries. This o-ring material also works extremely well with most acids and chemicals, as well as in extremely cold or hot environments.

Durometer (Hardness of O-ring) Availability:  60-75 (with 75 being the standard size)

Temperature Range: -15°F to 400°F

Works Well With:

• Most Acids and Chemicals
• Petroleum Oils/Fuels
• Silicone Oils/Greases
• Vacuum
• Halogenated Hydrocarbons
• Di-Ester Lubricants

Available in:
Series 100 Cartridge Valves
Series 100 Specialty Valves
Series 200 NPT Valves
Series 300 Modular Valves
Series 500 Miniature Modular Valves

Mechanical Properties:
EPDM has a “good” rating for resistance and a “moderate” rating for short-term resilience. To compare mechanical properties of all o-rings, view the chart below.

Note: Viton® has a “good” rating for wear, an “excellent” rating for both compression set and permeation resistance, and a “moderate” rating for short-term resilience.

BACK TO TOP »

SILICONE

Overview: With an excellent rating for sealing (versus other o-rings), Silicone works well with all eight plastic body materials offered by Smart Products USA. This particular o-ring material seals best because its compounds are very soft and will seat better with poppets and/or external bodies versus a harder material like Viton®. Silicone rubber also stays flexible over a wide temperature range, and its softness gives it better conformability than other rubbers. These o-rings are also odorless and non-toxic. Another bonus for our Silicone o-rings is that they are FDA Approved, which makes them a popular choice for certain applications within the medical or food and beverage industries. We can also offer Silicone with a Class VI status, upon request.

Durometer (Hardness of O-ring) Availability:  50-70 (with 70 being the standard size)

Temperature Range: -65°F to 450°F

Works Well With:

• Dry Heat
• Sunlight
• Ozone
• Weathering

Available in:
Series 100 Cartridge Valves
Series 100 Specialty Valves
Series 200 NPT Valves
Series 300 Modular Valves
Series 500 Miniature Modular Valves

Mechanical Properties:
Silicone has an “excellent” rating for both compression set and permeation resistance, and a “poor” rating for wear and short-term resilience. To compare mechanical properties of all o-rings, view the chart below.

Note: Great for gamma sterilization and/or autoclaving.

BACK TO TOP »

FLUOROSILICONE

Overview: With the widest temperature range (-80°F to 450°F) available of any o-ring we offer, Fluorosilicone is especially popular for really cold environments. Another bonus is its great resistance to chemicals.

Durometer (Hardness of O-ring) Availability:  70 (however, we do offer some valve models in a 60 durometer option)

Temperature Range: -80°F to 450°F

Works Well With:

• Jet Fuel
• Dry Heat
• Some Petroleum Oils
• Chlorinated Solvents
• Aromatic Mineral Oils
• Automotive Refrigerants
• Dilute Acids
• Dilute Alkalis
• Hydrocarbon Fuels
• Silicone Fluids

These characteristics make Fluorosilicone especially popular for use within the Military or Aerospace markets.

Available in:
Series 100 Cartridge Valves
Series 100 Specialty Valves
Series 200 NPT Valves
Series 300 Modular Valves

Mechanical Properties:
Fluorosilicone has a “moderate” rating for both compression set and short-term resilience, and a “poor” rating for wear and permeation resistance. To compare mechanical properties of all o-rings, view the chart below.

Note: Great for gamma sterilization and/or autoclaving.

BACK TO TOP »

AFLAS®

Overview: Only available in a durometer (hardness of the o-ring) size of 80, Aflas® is one strong o-ring. Ideal for tougher environments, particularly in the automotive industry, this o-ring is used in a lot of engine applications due to its high temperature resistance and excellent resistance against motor oils and coolants. This material has the ability to work really well with a variety of media, similar to EPDM and Viton® o-rings.

Durometer (Hardness of O-ring) Availability:  80

Temperature Range: -20°F to 400°F+

Works Well With:

• Steam
• Amines
• Petroleum Fluids
• Brake Fluids
• Phosphate Esters

Available in:
Series 100 Cartridge Valves
Series 100 Specialty Valves
Series 300 Modular Valves

Mechanical Properties:
Excellent resistance to petroleum products, steam, phosphate esters, amines and brake fluids. To compare mechanical properties of all o-rings, view the chart below.

Note: We are not able to offer Alfas® with a spring lower than 0.5 PSI.

BACK TO TOP »

KALREZ®

Overview: Working with really high temperatures and extremely caustic substances makes Kalrez® o-rings an option when no other o-ring will do the job. Kalrez®, known to be expensive throughout the marketplace, is an o-ring material that is still worth consideration if your application requires the use of harsh chemicals. Because Kalrez® works so well in extreme environments, cost can be justified with savings in other areas such as ensuring a device will run smoothly and efficiently because the o-ring seal is capable of resisting particularly rigid substances.

Durometer (Hardness of O-ring) Availability:  80 or 90

Temperature Range: -10°F to 615°F

Works Well With:

• Low Out Gassing
• Chlorine Wet/Dry
• Petroleum Oil
• Chlorinated Hydrocarbons

Available in:
Series 100 Cartridge Valves
Series 100 Specialty Valves
Series 300 Modular Valves

Mechanical Properties:
Kalrez® has a “good” rating for wear, compression set, and permeation resistance. It is rated “moderate” for short-term resilience. To compare mechanical properties of all o-rings, view the chart below.

Note: We are not able to offer Kalrez® with a spring lower than 0.5 PSI.

BACK TO TOP »

GAMMA STERILIZATION & AUTOCLAVING TEST

Gamma Radiation Effects at High Dosage (39.9kGy)

Grading Scale
A = No Visual or Functional Effects
B = Only Visual Effects
C = Only Minor Functional Effects
D = Visual & Minor Functional Effects
F = Major Functional Effects

BACK TO TOP »

MECHANICAL PROPERTIES

O-ring Mechanical Properties

Note: Our products are subject to continuous improvement. To achieve this goal, Smart Products USA reserves the right to change features, processes, materials, testing and other specifications as necessary. All plastic body material recommendations are based on standard corrosion resistant and compatibility guides. Smart Products USA strongly recommends that customers test products for each application-specific use. Buyer is urged to test and investigate the compatibility of any substance used with our products prior to actual use. Seller will not be responsible for the failure of Buyer to thoroughly test and investigate the compatibility of the substances used with our products and the fitness of the products for its particular use or application.

BACK TO TOP »

VIEW PLASTIC BODY MATERIALS PAGE »