How to Choose the Right Gasket Material for a Non-Metallic Gasket

Jun 12, 2019 Material | Gaskets

A gasket is a mechanical tool that helps seal connecting flanges and prevents leakage. It is used in various industries across applications and devices which include boilers, tanks, and piping among others. There is little doubt that these industrial gaskets have to withstand tremendous pressure, and are subjected to chemicals, fuels, and other hazardous substances. So, the material of these gaskets has to be robust, rust free and resistant to chemicals, abrasion, and more. Most metals react with certain chemicals or may wear out due to corrosion over time. Hence, non-metallic gaskets are commonly used for specific applications. This post discusses various types of materials that can be used to make non-metallic gaskets.

Choosing the Gasket Materials Based on the Application
There are various types of gaskets based upon their use or application, and their material, whether metallic, non-metallic, or semi-metallic, would be decided accordingly. Other factors include presence of chemicals or abrasive materials, extreme heat or cold, pressure bearing capacity, and others. Overall, the material of the gasket must match with all these requirements and withstand the required pressure and conditions. Here are some types of non-metallic materials used in gasket construction:

Teflon
Fiber glass
Cellulose
Ceramic fiber
Silicone
PTFE
Elastomers such as butyl and nitrile rubber
Graphite
Mica
Rubber

For highly corrosive applications and harsh environments, fiber glass, elastomers, graphite (flexible), and Teflon are the best options among non-metallic gasket materials. Here are some specific features of a few of these materials.

Mica: It has a good temperature resistance and hence is suitable for high-temperature applications across industries.
Teflon or PTFE: Teflon has a good chemical resistance and hence is suitable as a sealant in chemical industries as well as other application industries where chemicals are used in the end products such as cosmetics.
Rubber: Rubber has good compression properties. Synthetically-made rubber can be can be designed to be of use in extreme cold as well as hot conditions. Most synthetic rubbers such as butyl rubber are oil resistant; however, natural rubbers are not.
Ethylene propylene: It is good for applications that involve corrosive and hydraulic fluids.
Silicone: This may be an excellent choice for most materials except vapor and hydrocarbons. It can resist high temperatures and does not react with sunlight as well as ozone.
Cellulose: This being a natural fiber is suitable mostly in case of low to medium temperature and pressure conditions.
Glass: Glass has a reasonably good temperature and chemical resistance. It is a mixture of metal silicates and has a good strength.

So, for a non-metallic gasket to be leak proof and function well, it is essential to choose the right material based on criteria such as temperature resistance, chemical resistance, flexibility, friction, strength, relaxation & compression properties, and so on. Depending upon the type of properties you require in your application, you can choose the right gasket material.

You can get in touch with industry experts to select the right material for your application. SSP Seals is one of the leading manufacturers of non-metallic industrial gaskets, including flange gaskets, and has a vast experience in designing and delivering the same across industries.