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Five Energizers for PTFE Spring-Energized Seals

PTFE Seals

5-energized_PTFE-seals

PTFE spring-energized seals are a popular choice for engineers.  The reasons are many, including their long service life, even wear, and their ability to perform in some of the harshest environments.  They work well in extreme temperatures; can even perform well in situations where operating conditions can vary significantly.  They usually offer a low compression set, have a long shelf life, and work very well in non-lubricated applications.  The use of PTFE results in extremely low friction and excellent chemical compatibility and users can choose from a variety of spring energizers.

ptfe-teflon-spring-energized-sealsAs one of the key components of spring energized PTFE seals, each of these energizers offers a different set of characteristics that allow engineers to find just the type of seal to suit their application’s needs.  In this article, we are going to look at five different categories of energizers, and in what conditions they provide the best service:  coil springs, V springs, helical flat springs, cantilevered finger springs, and elastomeric O-rings.

 

Need more energizing? Check out these informative PTFE Spring Energized Seals articles from the Advanced EMC Technologies blog:

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Polymer Rolling Element Bearings: Deep Groove Ball Bearings

Polymer Roller Bearings

BallBearing-animation -CC licensing
Working principle for a ball bearing 
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Radial Deep Groove Ball Bearings (also known as Conrad bearings) are some of the most commonly used ball bearings.  In deep groove ball bearings, the dimensions of the raceways are almost the same as the dimensions of the balls.  The grooves consist of circular arcs with a radius just a little bit larger than the ball radius.  The groove depth is typically ¼ of the ball diameter.  This geometry of the bearing to carry radial, axial, and combined loads.  However, they are used when the primary load is going to be radial.  Its ability to carry an axial load depends on how much clearance there is in the bearing after installation: if the balls are able to contact the groove at an angle, then they can support a radial load.

plastic-bearing-double-rowYou can find them with either single or double rows. Double rows work well supporting moment loads that may be acting on the shaft. These bearings are usually not separable, and the raceway is continuous.  They are also not self-aligning, so it is important that they be correctly aligned when they are installed.  Also note that even if they are not going to be lubricated, deep groove bearings are going to need some type of seal or shield to protect them from contaminants that will compromise both their performance and life span.

 

More information on polymer bearings from Advanced EMC Technologies:

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