Find o rings, seals and Parker o-rings at Sealing Devices

O-Ring Sizes | Temperature Ranges | Chemical Compatibilty | Generic Elastomeric Properties

o-rings

Sealing Devices offers o-rings and seals from Parker Seal to help seal applications against fluids/liquids and gas loss. O rings are available as 'common' size stock materials, or can be custom made to fit into highly engineered glands. When an o ring is applied to a properly designed gland,
it will seal against a variety of high temperatures, cryogenic conditions, and chemicals. Although o rings and seals can be used in a variety of static and dynamic applications, they can also complement gaskets and other sealing devices.

Most o rings are made of elastomers including buna rubber, silicone rubber, flourocarbon rubber, nitrile rubber (NBR), butadiene rubber, chloroprene rubber, and perflourinated elastomers. Many sizes are available to fit most sealing applications, and they can be chosen from the Parker O-Ring Handbook below. There is also a useful chemical compatibility chart that compares several different elastomeric compounds, and displays each compounds chemical resistance to commonly used materials.

The o-ring handbook also lists a comparison of common properties of commonly used elastomers including Aflas, Butadiene, Butyl, Chlorinated Polyethelene, Epichlorohyrdin, Ethylene Acrylic, Ethylene Polypropylene, Fluorocarbon, Fluorosilicone, Isoprene, Neoprene, HNBR, Nitrile, Perfluoroeleastomers, Polyacrylate, polysulfide, polyurethane, SBR and silicone rubbers.

An important consideration for designing o-rings and seals is compression set, or the amount that an elastomer returns to its original thickness after having been compressed. Factors critical to compression set include the amount of squeeze over time, temperature variations, and fluid contact.

The most important criteria in choosing an oring include:

Compatibility between the o-rings and the fluid to be sealed.

Operating temperature (or a range of temperatures) are important when designing the gland to be sealed. A gland operating at a high temperature could require increase volume to compensate for the thermal expansion or swelling of the o-ring. Conversely, when low temperature sealing is required, a more shallow gland depth might result in producing the proper squeeze for an effective seal.

Pressure is important in determining the hardness, or durometer of an o-ring. The different durometer specifications can be determined by consulting the Parker O-Ring Handbook below.

(a) Rubber compound must be added when ordering by the 2-size number (i.e., 2-007 N0674-70).
(b) This chart provides dimensions for standard (AN) shrinkage materials ONLY, corresponding to AS568A dimensions. Compounds with different shrinkage rates (non-AN) will produce slightly different dimensions and tolerances.
(c) Call for more information when ordering to a Military, AMS or NAS material Specification.

.040 Area = .001256 (sq. in.)
.050 Area = .001964 (sq. in.)
.060 Area = .002827 (sq. in.)
.070 Area = .003848 (sq. in.)

.103 Area = .008332 (sq. in.)
.139 Area = .015175 (sq. in.)
.210 Area = .034636 (sq. in.)
.275 Area = .059396 (sq. in.)

Temperature Ranges

Chemical Compatibility

Compatibilty Tables for Gases, Fluids, Solids
Excerpt from the Parker O-Ring Handbook [53 pages]

Generic Elastomeric Properties

Physical Property	Butyl	Ethylene Propylene EPDM	Flouro-carbon FKM	Natural Rubber NR	Neoprene CR	Nitrile Butadiene NBR	Silicone VMQ	Styrene Butadiene SBR	Urethane
Polymer Specific Gravity	0.9	0.88	1.4-1.9	0.93	1.23	1	0.95	0.93	1.05
Durometer Limits	30-100	40-90	65-90	30-100	20-90	40-100	25-80	30-100	30-100
Tensile Strength, PSI	0-1900	0-2400	0-2000	0-3200	0-3000	0-3000	0-1450	0-3000	0-8000
Elongation %	0-625%	0-500%	0-300%	0-700%	0-800%	0-700%	0-700%	0-500%	0-600%
Tear Resistance	Fair	Fair	Fair	Very Good	Good	Good	Good	Good	Very Good
Weather Resistance	Very Good	Very Good	Very Good	Fair	Very Good	Fair	Very Good	Fair	Very Good
Ozone Resistance	Very Good	Very Good	Very Good	Poor	Very Good	Poor	Very Good	Poor	Very Good
Water Resistance	Very Good	Very Good	Good	Very Good	Good	Very Good	Good	Very Good	Fair
Oil & Gasoline Resistance	Poor	Poor	Very Good	Poor	Good	Very Good	Poor	Poor	Very Good
Solvent Resistance: Aliphatic Hydrocarbons	Poor	Poor	Very Good	Poor	Good	Very Good	Poor	Poor	Very Good
Solvent Resistance: Aromatic Hydrocarbons	Poor	Fair	Very Good	Poor	Poor	Good	Poor	Poor	Fair
Brittle Point (°F)	-80	-80	-60	-80	-50	-65	-180	-80	-60
Stiffening Point (°F) (avg)	-25	-35	-15	-40	-10	-10	-150	-35	-20
Compression Set	Fair	Fair	Good	Good	Fair	Good	Very Good	Good	Very Good
Temp Resistance:
To 212°F	Very Good	Very Good	Very Good	Fair	Good	Good	Very Good	Good	Good
To 350°F	Good	Good	Very Good	Poor	Poor	Poor	Very Good	Poor	Poor
To 450°F	Poor	Poor	Very Good	Poor	Poor	Poor	Very Good	Poor	Poor
Gas Impermeability	Very Good	Good	Very Good	Good	Good	Good	Fair	Fair	Good
Abrasion Resistance	Very Good	Good	Fair	Very Good	Good	Good	Fair	Very Good	Very Good
Flex Resistance	Good	Good	Good	Very Good	Good	Good	Very Good	Good	Good

This information gives typical properties and is not to be taken as a warranty or any representation for which we assume legal responsibility, nor as permission or recommendation. It is offered soley for your consideration, investigation, and verification.

Viton® and Kalrez® are registered trademarks of DuPont Performance Elastomers.

Customer Service: (716) 684-7600
Home | Contact Us | Request Quote | ^Top