Generally speaking, custom rubber gaskets in Ohio have one purpose: To create leak proof seals between components in machines.  To do this, the gasket needs to have a predictable size and shape, so that it doesn’t deform to the point it stops making a strong seal.

So, in most cases, it’s going to be a bad thing if the gasket swells in the application.  But is it always a bad thing?  As with most aspects of mechanical engineering, the reality isn’t so simple.

Why Do Custom Rubber Gaskets Swell?

Generally speaking, a rubber gasket will swell when the particular compound is not compliant with the system fluid or media.  This isn’t only true of custom rubber gaskets it can happen with virtually any  rubber based gasket material.

Petroleum products, and other hydrocarbons, have this effect on several compounds, most notably.  EPDM, and SBR.  Nitile, or NBR, is the preferred compound to use with petroleum based fluids.  Viton is also used with some petroleum based fluids containing additives that may harm NBR.  EPDM and SBR are typically used in hot water and steam applications that will adversely affect NBR.

When a gasket swells the sealing capability is threatened.   Depending on the amount of swell, and the strength of the gasket material, it could also cause parts to go out of alignment or cause other physical damage to the machine.  Additionally, too much swelling and shrinking will tend to cause damage to the gaskets themselves, reducing their lifespan and increasing their likelihood of failing entirely.

But can this tendency to swell be harnessed for useful purposes?  Yes!

Swelling Custom Rubber Gaskets Can Be Deliberate

While gasket swelling is usually something to avoid, there are situations where expert gasket engineers can make it work to their advantage.  In particular, there can be situations where gaskets are being called to seal unusual shapes or need to seal around objects.

For example, there may be cases where bolts or flanges are too small/weak to seal effectively on their own.  In these cases, having a gasket deliberately engineered to swell will seal any small gaps left in the machinery.   Using a deliberate swell is not common practice, and doing so should be discussed with a gasket expert before doing so.

This is why having experienced Ohio custom rubber gasket engineers on your side can be so useful. Experts can leverage the material properties of various gaskets for enhanced effects that solve real engineering challenges.  Contact Expert Gasket & Seal to consult on your own challenges!