Rules of Thumb Part II

Part 2 of a 2-Part series

Following is the next part of our Rules of Thumb series that Apple Rubber is providing in our e-newsletters.

We think you will find a small investment of your time in reading these rules will yield a greater knowledge and understanding of sealing principles. Here are a few more you should be familiar with.

1. The closer the application is to room temperature, the longer an O-ring can be expected to effectively seal.
2. Avoid using graphite-loaded compounds with stainless steel, as they tend to pit the stainless steel surface over time.
3. Before installation, make sure the lightly coat the O-ring with a lubricant that is compatible with the O-ring material, as well as with system chemicals.
4. When using only one back-up ring, be sure to install it on the low pressure side of the O-ring.
5. Static seal cross-sections are generally compressed from 10% to 40%, whereas Dynamic seals are from 10% to only 30%.
6. When it is said that an elastomer is good for an application it is meant that some compounds which include that material are acceptable. Not All. For instance, some compounds of EP are good for brake fluid applications, but most are not acceptable.

Look for more in future issues of this e-newsletter. ALL of these Rules of Thumb and more can be found in the Seal Design Guide sections of our web site. Visit www.applerubber.com.

1-800-828-7745