Category Archives: O-rings

Read more about O-ring seals in this collection of articles, which covers a variety of topics related to O-ring sizes and size standards, seal materials, installation, and much more.

TetraSeals: Alternate Sealing Solution

Article re-posted with permission from Parker Hannifin Sealing & Shielding Team.
Original content can be found on Parker’s Blog.


TetraSeal: An Alternate Sealing Solution When an O-Ring Isn’t Working

Parker TetraSeals

Our applications engineering team takes more than a few calls each month where the O-ring is leaking, either immediately or after just a short time in service. Once we drill down to the details, we learn the failure mode is an improperly sized groove and O-ring. It isn’t all that uncommon for a groove to be cut in a flange and a novice designer learns the hard way that standard O-rings cannot fit in just any groove geometry. For hardware that has already been machined, frustration ensues as the caller learns the O-ring solution requires tooling. Tooling can have a lead time of at least a month to cut and can cost thousands of dollars. Parker offers a TetraSeal® solution, which often does not require tooling and can be made of many of the same materials used for O-rings.

Benefits of TetraSeals

The TetraSeal is a circular precision-cut seal with a square cross-section. Unlike O-rings which require a unique mold for each material family and size, TetraSeals are extruded, cured and machine cut to the target thickness. Our manufacturing facilities in both Spartanburg, South Carolina and Goshen, Indiana are tooled in a variety of interchangeable extrusion dies, making this type of seal an easily sourced seal solution without the lead time and cost of a custom molded O-ring.

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O-Ring Selection Made Easy

Article re-posted with permission from Parker Hannifin Sealing & Shielding Team.
Original content can be found on Parker’s Blog.


O-Ring Selection Made Easy with the Parker O-Ring Selector

O-Ring Selector Tool - O-Ring Selection

Two things are equally important for the reliable performance of an O-Ring seal: the right size and the right material. Parker’s new O-Ring Selector is an engineering tool that enables users to make the right material and size selections easily, quickly and reliably – in a single application. The accuracy of the results ensures the desired performance of the O-Ring in the subsequent application. This is primarily based on the fact that both functionalities – the material selection and the O-Ring size calculation – are closely interlinked. This achieves a new quality in calculating the total sealing system.

Overview of the O-Ring Selector

The Parker O-Ring Selector is divided into three main sections:

  • Service Conditions & Material Selector
  • Size Selector
  • Notes

O-Ring Selector Tool - O-Ring Selection - Service Conditions & Material Selector

The Service Conditions & Material Selector section is focused on mapping the material-related application conditions. Entering the operating temperature range, the desired polymer family and/or material hardness will take the user to the suitable material selection. The Advanced Material Selector enables experienced users to specify the operating conditions in even greater detail. Here the medium to be sealed can be selected from a database containing 2,500 media. In addition, a search for required approvals and conformities can be run.

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NEW! Elastomer Failure Modes – Part 4

Failure ModesGallagher recently published its Failure Modes of Elastomers in the Semiconductor Industry White Paper, now available for download on our site.  This white paper discusses common issues that occur with elastomer seals in the semiconductor industry. The excerpt below is the fourth and final section of our new white paper, discussing Volatiles (offgassing) and Particle Generation.  To download the white paper in its entirety, visit our Resources Page, or click on the image to the right.


Failure Modes of Elastomers in the Semiconductor Industry

Failure ModesHigh performance elastomers are found in many applications in the semiconductor industry (see paper titled Perfluoroelastomers in the Semiconductor Industry). Though perfluoroelastomer (FFKM) seals are formulated to meet the highest performance requirements of integrated circuit (chip) manufacturers, even these elastomers can’t solve every sealing application nor will they last forever in service. Additionally, end users need to understand subtle performance differences between perfluoroelastomers in the same product line. For example, one product may be better at minimizing particle generation while another may be better for high temperature services.

Continue reading NEW! Elastomer Failure Modes – Part 4

NEW! Elastomer Failure Modes – Part 3

Failure ModesGallagher recently published its Failure Modes of Elastomers in the Semiconductor Industry White Paper, now available for download on our site.  This white paper discusses common issues that occur with elastomer seals in the semiconductor industry. The excerpt below is the third section of our new white paper, discussing O-Ring Stretch, Chemical Attack, Plasma Cracking, and Permeation.  To download the entire white paper, visit our Resources Page, or click on the image to the right.


Failure Modes of Elastomers in the Semiconductor Industry

Failure ModesHigh performance elastomers are found in many applications in the semiconductor industry (see paper titled Perfluoroelastomers in the Semiconductor Industry). Though perfluoroelastomer (FFKM) seals are formulated to meet the highest performance requirements of integrated circuit (chip) manufacturers, even these elastomers can’t solve every sealing application nor will they last forever in service. Additionally, end users need to understand subtle performance differences between perfluoroelastomers in the same product line. For example, one product may be better at minimizing particle generation while another may be better for high temperature services.

Continue reading NEW! Elastomer Failure Modes – Part 3

Parker’s Rapid Prototype Program

Article re-posted with permission from Parker Hannifin Sealing & Shielding Team.
Original content can be found on Parker’s Blog.


Rapid Prototype ProgramThe O-Ring & Engineered Seals Division is now offering a rapid prototype program for solid and hollow spliced O-rings that will reduce lead times on small orders to improve sample and trial testing on enclosure projects. The program provides spliced rings available in a variety of cross sections and can be purchased in either solid or hollow profiles.

Spliced ring sizes

In the event that enclosure tolerances are large or the available compressive force is low, Parker engineers can design a custom hollow seal to help absorb large tolerances while providing very low compressive force compared to solid cord. Spliced rings with large inside diameters up to 95” are available in silicone and nitrile materials. Rings with inside diameters up to 57” are available in fluorocarbon. Cross sections of .070”, .103”, .139”, .210” .250” are regularly stocked and available to splice to the ring ID needed. The chart below outlines the current compounds, cross sections, and diameters available under the program.

Continue reading Parker’s Rapid Prototype Program

NEW! Elastomer Failure Modes – Part 2

Failure ModesGallagher recently published its Failure Modes for Elastomers in the Semiconductor Industry White Paper, now available for download on our site.  This white paper discusses common issues that occur with elastomer seals in the semiconductor industry. The excerpt below is the second section of our new white paper, discussing Loss of Sealing Force, and Extrusion.  To download the white paper in its entirety, visit our Resources Page, or click on the image to the right.


Failure Modes of Elastomers in the Semiconductor Industry

Failure ModesHigh performance elastomers are found in many applications in the semiconductor industry (see paper titled Perfluoroelastomers in the Semiconductor Industry). Though perfluoroelastomer (FFKM) seals are formulated to meet the highest performance requirements of integrated circuit (chip) manufacturers, even these elastomers can’t solve every sealing application nor will they last forever in service. Additionally, end users need to understand subtle performance differences between perfluoroelastomers in the same product line. For example, one product may be better at minimizing particle generation while another may be better for high temperature services.

Continue reading NEW! Elastomer Failure Modes – Part 2

NEW! Elastomer Failure Modes White Paper

Failure ModesGallagher recently published its Failure Modes of Elastomers in the Semiconductor Industry White Paper, now available for download on our site.  This white paper discusses common issues that occur with elastomer seals in the semiconductor industry. The excerpt below is the first section of our new white paper, discussing groove design and seal leakage.  To download the entire white paper, visit our Resources Page, or click on the image to the right.


Failure Modes for Elastomers in the Semiconductor Industry

Failure ModesHigh performance elastomers are found in many applications in the semiconductor industry (see paper titled Perfluoroelastomers in the Semiconductor Industry). Though perfluoroelastomer (FFKM) seals are formulated to meet the highest performance requirements of integrated circuit (chip) manufacturers, even these elastomers can’t solve every sealing application nor will they last forever in service. Additionally, end users need to understand subtle performance differences between perfluoroelastomers in the same product line. For example, one product may be better at minimizing particle generation while another may be better for high temperature services.

Continue reading NEW! Elastomer Failure Modes White Paper

Selecting the Right O-Ring Squeeze Ratio

Article re-posted with permission from Parker Hannifin Sealing & Shielding Team.
Original content can be found on Parker’s Blog.


One of the decisions equipment designers need to make when installing O-ring seals in their applications is how much the O-ring will be squeezed by its mating hardware to create an effective seal.

What is O-ring squeeze

O-Ring Squeeze RatioSqueeze is a ratio of the amount of deformation applied to the seal expressed as a percentage of the free-state cross-sectional thickness. Deforming the seal cross-section “energizes” the elastomer matrix much like compressing a spring; the inherent elasticity of the rubber material causes it to push back against the mating components. This contact force blocks the passage of liquids, gases and dry powders, preventing them from flowing between the rubber seal and the mating hardware.

The greater the squeeze, the more force is applied against the hardware and the tighter the seal. But that doesn’t necessarily mean that designers should always specify the most squeeze (assuming they knew what that level was or why it was “the most”). There are a number of factors to consider, which include:

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How To Install an O-Ring in any Application

O-Rings continue to be the most widely utilized sealing product.  While the ‘Donut’ shaped profile has by and large been kept intact since their inception, continued elastomeric development has pushed o-ring temperature and chemical compatibility to limits unimaginable several decades ago.

Typically, O-Rings fail due to adverse effects of a number of factors, from improper installation and lubrication to incorrect size and design.  The collection of videos below will help you minimize installation errors that may lead to failure (be sure to bookmark this page for future reference).


How To Install an O-Ring – Standard Male Gland

Continue reading How To Install an O-Ring in any Application

VIDEO: How to Lubricate an O-Ring

Lubrication of O-rings is extremely important. The greatest benefit of using a lubricant is typically obtained during installation.

Parker O-Lube - Lubricant for O-RingsUsing a lubricant is going to decrease the surface friction of the O-ring helping to prevent abrasion, pinching or cutting of the O-ring during installation.  Lubricating an O-ring can also help to seat the O-ring properly into the application, as well as aid and speed up automated assembly processes.

The proper method of applying a lubricant to an O-ring always seems to be an area of concern for many of our customers and there are many methods used in the marketplace. One is to apply the lubricant to the O-ring using your fingers, your hand or a brush. Another is to dip the O-ring into a container of the lubricant. A third method commonly used is to dispense the O-ring lubricant into the seal packaging and use what we call the “shake and bake” method.

The common goal of all of these different lubrication methods is to have a thin uniform film applied to the entire surface of the O-ring when completed. This will ease installation and provide best friction reduction.


Gallagher Fluid Seals is a Parker Authorized Distributor, with thousands of o-rings stocked at all times.  If you have any questions about o-rings, material compatibility, failure modes, etc, please don’t hesitate to contact us.