Elastomers: A Beginner's Guide

By Liz Braden, CSI

Whether for a gasket, valve seat, or O-ring, the choice of elastomer might seem like a minor decision, but it can have a major impact. If a seal material is a poor fit for the application, you could run into any number of problems, from swelling to peeling or cracking. Needless to say, these could be a big deal in a sanitary process. But how to you decide what elastomer to use?

Your best bet is always to look at what is already being used in the same or a similar application. With variables like chemical compatibility, temperature, pressure, and mechanical wear, it's almost impossible to predict with certainty what the best material will be. In most cases, several materials will work, but you might see a longer life in some. At that point, it's a judgment call, where the life can be weighed against the cost. If you're happy with how a gasket is performing and you're happy with the price, there is usually no need to change materials.

But what if you're starting from scratch?