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Molded O-Rings

The O-ring is a simple and versatile seal that can be used in thousands of applications. O-rings are manufactured in a wide variety of compounds to suit your every need.

Dynamic Sealing

The O-Ring moves relative to the mating surface. A moving seal may be further classified by the type of motion: reciprocating, oscillating, or rotating.
The greatest number of dynamic seals are used in reciprocating service in cylinders, valves, and linear actuators. Oscillating motion is encountered in swivels and valve stems.
When an O-Ring is used on a rotating shaft, it should be limited to light duty where the shaft speed is low and some fluid bypass is acceptable.

Static Sealing

Most O-Rings are used in static service (the O-Ring and metal surfaces remain relatively fixed). They may be applied as face seals or radial seals. In face seal applications, the O-Ring should seat against the low pressure side of the groove.


Buna-N, Viton(Fluorocarbon), EPDM, Silicone, PTFE, Polyacrylate, Kalrez,HSN (HNBR),Neoprene, AFLAS, Polyurethane

Durometer Selection

70-durometer hardness should be used wherever possible as it offers the best combination of properties for most O-Ring applications. Softer compounds stretch easier and seal better on rough surfaces. Harder compounds offer greater abrasion resistance and resistance to extrusion.


Inch Size Buna O-Rings (Nitrile)

This compound has excellent resistance to a wide variety of fluids, good tensile strength, high elongation, low compression set, and excellent resistance to abrasion and tear. This O-Ring is the most widley used seal due to its simplicity.

Temperature Range: -65° F to 250° F

Usual Colour: Black

Hardness Durometer: 70 Duro

Trade Name: Chemigum®, NySyn, Hycar®, Paracril®, Kyrnac®

Colour: black, white


Boss Tube Fitting Buna O-Rings

Durometer: O-Ring sizes for Boss Tube Fittings are available in 70 Duro

Application: providing a seal for straight-thread tube fittings on a boss.
Numbering System: The two digits after the -9 represent the Tube Size O.D. in 16ths of an inch.

For example -905 is sized for a Tube O.D. of 5/16″.

The one exception is for -901 where the Tube Size O.D. is 3/32″.

Buna (Nitrile/NBR)
70 Duro

Colour: black


Metric Size Buna O-Rings

Metric Size O-Rings in buna material

Cross Section can be found from 1mm up to 8.4mm.

Numbering  system is ID x Cross Section:

Eg 5mm ID x 1mm Cross Section = 5-1MM

  • Buna (Nitrile/NBR)
  • 70 Duro

Colour: black


Viton O-Rings (Fluorocarbon (FKM,FMC))

This compound has a excellent resistance to a wide range of chemicals, excellent high temperature stability,excellent resistance to petroleum products, good resistance to weathering, ozone, oxygen, high temperature and flame.

Standard Inch Viton O-Rings sizes ranging from 1/32″ I.D. to 26″ I.D.

Trade Names: Viton, Fluorel

Colour : brown


EPDM O-Rings (Ethylene Propylene)

This Compound has a high tensile strength, elongation, good low temperature flexibility, outstanding heat aging.

Standard Inch EPDM O-Rings sizes ranging from 1/32″ I.D. to 26″ I.D.

Trade Names: Vistalon, Epsyn, Fpcar, Royalene, Nordel

Colour : Black


Silicone O-Rings

This compound has excellent resistance to temperature extremes and excellent dry heat resistance

Standard Inch Silicone O-Rings sizes ranging from 1/32″ I.D. to 26″ I.D.

Trade Names: Silastic, Thermoflex

Colour: Red


HSN-80 O-Rings

Hydrogenated Acrylonitrile Butadiene (HNBR), also known as Highly Saturated Nitrile (HSN) is superior to NBR in low brittle temperature, heat, oil, oil additive and sour oil resistance, and is far more resistant to sour gasoline and ozone than NBR.

Standard Inch HSN-80 O-Rings sizes ranging from 1/32″ I.D. to 26″ I.D.

Trade Names: HNBR, Therban, Zetpol, Tornac

Colour: Black


Aflas O-Rings (TFE )

This compound provides an advantageous combination of high temperature, chemical and electrical resistance properties.

Standard Inch AFLAS O-Rings sizes ranging from 1/32″ I.D. to 26″ I.D.

Trade Names: TFE

Colour : Black















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