O-Rings are one of the most common seals used in machine design today. A mechanical gasket in the shape of a doughnut, an O-Ring is a loop of elastomer with a round cross-section, designed to be placed in a groove and compressed during assembly between two or more parts, creating a seal at the interface. They are inexpensive, easy to make, and reliable. Like everything though, O-Rings sometimes fail or break, and need to be replaced. O-Rings can fail for a variety of different reasons. Today we discuss some characteristics that help us identify a damaged O-Ring material, causes of failure, and when they should be replaced.
If your O-Ring is not performing as you expected, and there is visual damage, it does not necessarily mean you have a damaged one. It could just mean you have the wrong size O-Ring for the application you are using it with. Once you confirm the appropriate size, here are some troubleshooting tips for identifying damaged O-Rings.
- The O-Ring develops circumferential splits within the flattened surface. This is usually due to excessive compression.
- The O-Ring exhibits blisters, pocks, or pits on its surface, due to rapid pressure changes.
- The O-Ring exhibits small cuts, nicks or gashes. This is typically from installation damages.
- The O-Ring or parts of it exhibit a flat surface parallel to the direction or motion. Loose particles and scrapes may be found on the seal surface, due to friction from a rough sealing surface.
- The O-Ring develops ragged edges which appear tattered, typically due to excessive clearances.
- The O-Ring may exhibit radial cracks located on the highest temperature surfaces. In addition, certain elastomers may exhibit signs of softening. This is due to exposure to excessive heat.
- The O-Ring may exhibit many signs of degradation including blisters, cracks, voids or discoloration, due to chemical incompatibility.
Any of the above conditions warrant the replacement of your O-Ring. A good rule of thumb is to replace your O-Rings once a year.
When It’s Time To Replace Your O-Rings
When it’s time to replace your O-Rings, Manufacturer’s Rubber & Supply has you covered. Not only do we carry a wide variety of O-Rings, we also carry an abundance of O-Ring material and resources that will make your job even easier. We offer the following:
- Kits & Accessories: Our O-Ring Kits and accessories come in a variety of packs for a range of industries and applications.
- O-Ring Sizing Chart: Free, downloadable sizing chart which will help you with your selection for the job at hand.
- Parker O-Lube: Barium base petroleum grease that can be applied during the installation of O-Rings to prolong life and usage.
- Parker Super O-Lube: A more durable silicone-based lubricant to extend the life of your synthetic rubber seals.
- Parker O-Ring Installation & Extraction Tools: Brass tools to help with install and replacement.
- Parker O-Ring Sizing Gauges: For precision O-Ring sizes.