Why O-Rings Fail (And What You Can Do About It)

Most mechanical systems and components rely on proper seals to function properly. Seals prevent leakage of fluids or gases, ensuring machinery efficiency. Gaskets are some of the standard seals used in most mechanical or manufacturing equipment and systems. Generally, O-rings are some of the most used gaskets in hydraulic, dynamic, pneumatic and static components. From valves to connectors, pumps and cylinders, O-rings help create the perfect seal between surfaces. They are dependable, easy to manufacture, and highly dependable.

Typically, O-rings are designed to last. However, several factors can contribute to premature failure. Knowing some of these factors will help you avoid them and get the most out of your O-rings. Here is an in-depth look into some of the causes of O-ring failure.

Using The Wrong Size Of O-Rings

Like any mechanical device, O-rings come in different sizes to suit different applications. And you must choose the correct size because getting it wrong is an invitation to failure. Too large or too small an O-ring will not serve its purpose effectively. For instance, an O-ring too large won't create the perfect tight seal you need. On the other hand, one too small won't hold up well to the pressure and may rupture or become damaged easily.

When considering the O-ring size, the critical dimensions to look at are the internal and external diameters and the cross-sectional width. Therefore, evaluate your needs carefully to ensure you select the perfect size.


Abrasion is another common cause of O-ring failure. Abrasion occurs when the O-rings and the components it's housed within repeatedly come into contact, gradually causing the O-rings to wear and eventually fail. Failure resulting from abrasion is usually visible because you can easily notice lacerations and grazed surfaces on the O-rings and the surrounding components. In addition, it's common in dynamic applications involving oscillating motion.

Generally, abrasion originates from poor lubrication practices. Therefore, ensure you properly and regularly lubricate your O-rings. Contaminated fluid may also contain abrasive particles that can contribute to abrasion damage, so be sure to inspect your system fluid regularly and change it if contaminated. In addition, poor surface finishes on the metal surfaces in your machinery and other mechanical equipment can also cause abrasion, so be keen to check on that as well.

Compatibility Issues

In what environmental conditions will the O-ring operate? Most importantly, consider the temperature and chemical conditions. It's always best to ensure the O-ring material you select is compatible with your application's chemical conditions and temperature levels to prevent failure from chemical degradation and thermal damage.