Graphite is a non-porous material with a high melting point. Graphite gaskets are primarily used for high-temperature, high-pressure sealing solutions.
Some common examples of graphite gasket uses are exhaust pipes, head gaskets, oil and petrochemical facilities, vehicle engines, corrugated metal gasket coatings, and dynamic or shaft seals.
In addition, they are often looked at as non-metallic and non-asbestos gasketing alternatives.
GRAPHITE GASKET MATERIAL:
Flexible graphite is a soft material that can get into surface irregularities once compressed, leading to a sealing effect. It can also be used as dynamic seals for equipment in motion because it has some natural lubricant that minimizes shaft wear.
Some graphite properties depend on the level of purity of the material you use. For instance, high-purity graphite can be brittle, which isn’t suitable for every project. You’ll want to choose a material that suits your purpose or factor additional support into your final design.
Additional support often comes in laminated foils or attached wire mesh, reinforcing the gaskets.
MAXIMUM TEMPERATURE FOR A GRAPHITE GASKET:
Graphite can typically withstand temperatures up to 850 degrees Fahrenheit, although this could depend on the material blend.
Compared to other heat resistant gasket materials, graphite gaskets have a lower thermal expansion, meaning they’ll keep their size under the high temperatures they might encounter. Thermal expansion can cause pipes carrying hot water or steam to burst.
You might therefore choose a graphite gasket, which has a low chance of changing shape, for high-temp applications where you don’t want thermal expansion.
Finally, it’s worth noting that lower-grade graphite might contain impurities that oxidize in temperatures lower than expected, causing seal failure. Matching the grade of your graphite to your temperature requirement will help prevent these types of accidents.
