Knowledge of Graphite Gaskets

Graphite gaskets are applied to sealing stuffing boxes of equipment such as all kinds of valves, pumps and reactors at high temperature and high pressure. Sealing performance of a flexible graphite gasket can almost remain the same at a temperature range of very low temperature to 400℃. A flexible graphite gasket has remarkable chemical resistance to almost all liquids except strong oxidized acids. Too tight installation doesn't influence flexible graphite gaskets, because flexible graphite gaskets have very small cold deformation and ductility.

Flexible graphite composite gaskets which are also known as reinforced graphite gaskets are made of graphite plates through punching or cutting. They have good corrosion resistance, low temperature resistance, high temperature resistance, excellent compressive and resilient properties and high strength.

The commonly used inner reinforcing materials for reinforced graphite gaskets are SS304, SS316 and tinplate, and thicknesses of reinforced graphite gaskets are from 0.1 to 0.127mm. The often used material is 304 reinforced graphite, and it can be made into circular various geometric gaskets, which can be widely used for pipes, valves, pumps, pressure vessels, heat exchangers, condensers, generators, air compressors, exhaust pipes, refrigerating machines, etc. Reinforced graphite gaskets can be cut into gaskets with complicated shapes such as gaskets for water gauges, punched flange gaskets and cylinder gaskets for automobile diesel engines.

High strength graphite gaskets can be made into the following gaskets according to the requirements.
1. Basic graphite composite gaskets
2. Inner overlaid graphite composite gaskets
3. Outer overlaid graphite composite gaskets
4. Inner and outer overlaid graphite composite gaskets.
The overlaid graphite composite gaskets not only can keep their original outstanding performance, but also are easy to be installed, disassembled and not easy to be damaged. Meanwhile, the overlaid graphite composite gasket can prevent itself from being corroded by the media and improve pressure resistance. The often used overlaid materials are stainless steel 304 and 316.

The maximum processing size of the graphite composite gasket is from 20 to 5000mm, and special specifications or various non-standard gaskets can be made based on customers' requirements. Flexible graphite is resistant to most chemical media except strong oxidative acids, including radioactive chemical media, while asbestos gaskets have poor adaptability and can not be used for radioactive media. Some chemical towers and heat exchangers require no heat insulation for the connecting parts. Flexible graphite can achieve this effect, but asbestos gaskets can not.

Applications of graphite gaskets
Graphite gaskets are applied to various industrial pipe flanges, heat exchangers, valve bonnets as well as flanges with special shapes for liquid level indicators and water levels.