What Material Should I Use?

Important: If you have any uncertainties about what material to use, just call us! We have employees that have been selling gaskets and servicing gasket applications for decades. We have sold gaskets in over 100 different materials!  What follows below are generalizations for different categories of gasket materials.  Use the information below only as a general guideline, and not as advice for your specific application.   

General Principles: Remember, the purpose of a gasket is to create a seal between two uneven surfaces. To accomplish the end goal, we generally face trade-offs amongst the materials. Whether it is cost vs. performance, softness vs. hardness, etc., gasket materials have different traits. Some are super soft and thus fill gaps between surfaces very well.  But that material may be susceptible to swelling from certain fluids, like oils. Alternatively, some materials may be too soft for a given application and can't handle the pressure of a given system.  Or that material may lose torque from creep relaxation and thus isn't hard enough. No matter what your application is, we can work with you to find the most cost-effective, solid-performance material for your application.

Rubber and Synthetic Rubbers: Rubber and synthetic rubber gaskets are some of the most common materials used in gasket applications. This is due to their inherent properties as elastomers. They typically, bend, stretch, twist, flex and conform to other shapes easily. This makes them a very good options to fill up the nooks and crannies between the two uneven surfaces (flanges) we are trying to seal. Rubbers, however, can face significant limitations in certain situations where temperatures become too cold (or hot) or if it comes in contact materials that don't play well with rubber.  Moreover, in some cases, if materials are too soft, creep relaxation can lead to a lack of load or force (compression) from bolts and ultimately a lack of seal.

Fiber-Based Gaskets:  Strands of fibers (often aramid fibers) combined with assorted binders, are compressed to create the raw material for fiber-based gaskets.  Gaskets from these materials are generally able to withstand higher temperatures than their rubber and synthetic rubber brethren. Gaskets cut from these compressed sheets, offer improved torque retention. This means that the initial load on the bolt that is compressing the gasket is better retained. Without this retained compression, the gasket may lose its sealing capability. Fiber-based gaskets also tend to have improved resistance to oils and hydrocarbons making them a solid choice for many industrial applications.

Graphite Gaskets:  Compressed graphite gaskets perform very well in harsh conditions. They can withstand higher temperatures and pressures than synthetic rubber or fiber-based gasket materials. Graphite gaskets can also withstand aggressive chemicals more than most other common gasket materials. Graphite gaskets are thus frequently used in chemical plants, refineries and paper mills.

PTFE (Teflon®) Gaskets:  Simply, PTFE is a plastic incredibly resistant to chemicals, making it an ideal gasket material in certain applications. Technically, polytetrafluoroethylene is a fluoropolymer (contains flourine and carbon) originally developed by DuPont® in 1938. PTFE has one of the lowest coefficients of friction of any solid. It is non-reactive, partly because of the strength of carbon–fluorine bonds, and so it is often used in containers and pipework for reactive and corrosive chemicals. (more technical info)  PTFE is commonly used in applications with corrosive chemicals, as well as in food processing and pharmaceutical applications.  However, PTFE has lower heat thresholds than graphite or fiber-based gasket materials.  

Gore® Gaskets: Gore® gasketing material is one of the most advanced gasketing materials.  Gore® gaskets can withstand temperatures from -450°F to +600°F.  They seal at low bolt loads, conform to flange deviations, exhibit high dimensional stability, resist creep and cold flow, and are highly resistant to blowout.  As a premium material, Gore® gaskets are typically more expensive than most other materials, limiting their application in many cases.  

Spiral Wound Gaskets: Flexitallic® is the gold standard in spiral wound gaskets. The concept of spiral wound gasket construction was originated by Flexitallic in 1912. The primary purpose for this development was the increasingly severe temperatures and pressures used by U.S. refinery operators in the first half of the century. The effects of pressure and temperature fluctuations, the temperature differential across the flange face, together with bolt stress relaxation and creep, demand a gasket with adequate flexibility and recovery to maintain a seal even under such conditions. Spiral wound gaskets can operate in extreme temperatures, under immense pressure and with nearly any corrosive or toxic media.