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The Best Methods for Installing an O-Ring

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O-Ring seals are a driving force behind many fluid power applications. Without proper o-ring installation, the seal can fail, causing leaks and potentially catastrophic system failures. In order to meet strict industry standards, o-ring production requires careful design, material selection and installation procedures.

There are important guidelines you should follow to properly install an o-ring seal. Ensuring that the seal is well lubricated, matches the correct size and is designed with the application in mind are important factors to check for during the installation process. Apple Rubber recommends the following methods for ensuring your o-ring will be installed correctly.

Make sure to use proper lubrication.

Lubrication can help with reducing surface friction and creates a smooth transition for installation. Choosing the proper lubricant requires careful consideration of the seal, lubricating formula and system as a whole. You must ensure the lubricant is compatible with the o-ring material to avoid shrinkage or swelling.

After testing compatibility with the sealing material, you must also ensure the lubricant can handle the temperature ranges of the application, is compatible with the system fluids and will not clog the system filters. This will affirm that there are no complications during the sealing application and the o-ring can function to its fullest potential.

Double check your sizing.

Before installing an o-ring, it’s important to verify the sizing to confirm you have the right seal for the application. The wrong sized o-ring can lead to serious damages for both the seal and the entire system as a whole.

Manufacturers should administer qualification testing for o-ring seals to ensure they are sized correctly and meet the customer’s standards. Apple Rubber utilizes CAM for dimensional testing, which automatically measures the product for specific dimensions. Since this testing machine is automated, there’s low risk for mistakes in measurement. Testing for specific measurements is crucial, as it allows for both Apple Rubber and the customer to be confident that their seal will work to its fullest potential.

Design with the application in mind.

One of the best ways to ensure your machinery and seal will last with minimal repairs is by following good design principles. To provide customers with an effective seal, the o-ring’s inside diameter must be smaller than the piston groove diameter. The o-ring should be slightly stretched, fitting snugly in the groove. The stretch should be between 1%-5%, with 2% being ideal in most applications. Also, a good seal design will provide more gland void than seal volume. The maximum seal volume should not exceed 90% of the minimum gland void.

Material selection is also a critical point in the design process. Take into consideration the temperature and pressure limitations, as well as the friction and durometer when choosing the material for your o-ring. This will prevent any future complications or failures in your o-ring.

From the design process to installation, o-rings should consistently be checked and verified that they are the right size, shape and material for the application. By following specific guidelines for installation, you can be sure your o-ring will work to its fullest potential.


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