How Do Fittings Work?
How Do Fittings Work? We’ve taken some time to learn some basics about fittings, and we’ve even gone over some new vocabulary. Now, let’s see if we can figure out how they actually work. But first, we need to lay some groundwork. Whenever we talk about “fittings” from now on, we’ll most often be referring to the combined nut and ferrule system. (Be aware that some fittings have both the nut and the ferrule together as one piece, as mentioned on the previous page).
Now, let’s dig in! To understand how fittings work, it’s important to know what fittings have to DO. Specifically, fittings have two primary functions:
These jobs may sound somewhat mundane; however, when you consider the nature of the chemicals that often travel along a given flow path, coupled with the high pressures that often exist inline, you may begin to realize just what a difficult job fittings have!
So, how do fittings do what they have to do? Most laboratory equipment fittings generally work through a process called external compression. In other words, as a fitting holds a piece of tubing in place, it compresses the outside (or external) wall of the tubing. Depending on the material used to make the fitting, this external compression either becomes permanent, through a process called swaging, or remains temporary, holding the tubing using simple friction against the tubing wall.
Preventing Liquid (or Gas) From Leaking Out of the Flow Path Holding Tubing in Place Against Opposing Pressure
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FITTINGS 101
