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Custom and Standard AS568 O-Rings

  • o-ring cord stock
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O-rings are a torus (or donut) shaped mechanical gasket that is designed to prevent the passage of liquids or gasses. They are usually installed into a machined or molded groove of a surface that needs sealing.

An o ring will sit in the middle of a gland when it’s at rest, but as pressure begins to rise in the sealing system, the O-ring shifts to the opposite side of the pressure. The ring is squeezed to plug the hole between the two mating hardware pieces.

Ace Seal offers extensive o-ring manufacturing capabilities including a comprehensive selection of elastomers and sizes for standard imperial, metric, and special applications. Ace Seal can provide o-rings to seal practically any application.

Contact Ace Seals for Your Standard and Custom O Ring Needs

With Ace Seal, you’re not limited to common industry o-ring sizes. We manufacture standard and custom o-rings in AS568 sizes and profiles to accommodate your static or dynamic applications.

To get started on customized o-rings, use the filters below to find the AS568 o-ring option you need, defined by inside diameter (ID) and the cross section (CS). Then, click on the link to specify the material, hardness, and color your application requires and request a custom quote.

Request a quote on custom AS568 rubber o-rings, or contact us discuss your unique needs.


Gaskets Vs. O-Rings

Gaskets and o rings have similar constructions, but they have important differences. A gasket is usually a flat sheet made from a variety of soft materials, including cork, rubber, plastic, and more. There are several types of gaskets, some of which require a flat flange and a bolted joint. O-rings seals, on the other hand, are thicker with rounded edges. They are precisely molded to fit into specific profiles.

O-rings also serve different purposes than gaskets. Both prevent fluids from escaping, but o rings are typically used for high pressure applications where a regular gasket made of cork, paper, or rubber would not hold up. They are well-suited for both static and dynamic applications and tend to be cost-effective.

Common O-Ring Failures and Prevention Methods


Abrasion is usually caused by improper finish of the surface in dynamic contact with the o-ring. If the surface around the o-ring is too abrasive, or even too smooth, the surface will be unable to hold lubricant. It could also be caused by excessive temperatures or contamination of system fluid by abrasive particles.

Solutions to this problem include adding proper surface finish and adequately lubricating the o-ring. Lubrication within the o ring reduces friction and the risk of wear over time.

Excessive Swelling

Swelling of the o-ring is caused by the absorption of surrounding fluids. The o ring will continue to swell passed the appropriate point if the seal materials are not compatible with the system environment. The swelling can lead to gland fill, extrusion and loss of sealing.

In order to prevent this failure, be sure to choose the proper o-ring material for your application. You will need a material that is able to interact with its surrounding environment and any fluids it may come into contact with. If you are unsure of what material to choose, the experts at ACE seal can help.

Compression Set

This is the most common cause of o-ring failure. It is caused when the integrity of the seal line is affected by an improper amount of seal squeeze. This happens because of several conditions, including the o-ring being made with inherently poor compression set properties. It can also be caused by improper gland design, excessive temperature, swelling, or over-tightening.

By inspecting your o-rings for effective properties before use, you can prevent this condition. You can also reduce the operating temperature and check for any built up heat at the seal interface.

Request a quote on custom AS568 rubber o-rings, or contact us discuss your unique needs.