Introduction of six types of flange gaskets
Flange gaskets are used for pipe flange connection, they are seals between two flanges. Medium, pressure and temperature directly influence the selection of flange gaskets.
1.Graphite gasket
This is a flat gasket made of flexible graphite, suitable for high temperature and strong corrosive medium.
2.Metallic gasket
There are three main types:
1.Graphite gasket
This is a flat gasket made of flexible graphite, suitable for high temperature and strong corrosive medium.
2.Metallic gasket
There are three main types:
- Octagonal and elliptical gaskets—suitable for wafer butterfly valves with trapezoidal groove flange type A.
- Tooth form is a tooth ripple machined on the sealing face of metal flat gasket—suitable for concave-convex flange sealing face.
- Lens gaskets—suitable for lens flange sealing face.
Metallic gaskets require high machining accuracy and surface roughness of the sealing face, usually used in high temperature and high pressure valves.
3.Graphite gasket coated with metal
It is made of spiral wound asbestos gaskets coated with thin metal, usually used in high temperature and pressure.
4.Spiral wound gasket
It is made of a mixture bind of corrugated metal and sealing materials, such as steel strip-asbestos, steel strip-PTFE, steel strip-flexible graphite, etc., suitable for high temperature and medium pressure valves.
5.PTFE gasket
Generally used for tongue-and-groove sealing face, mainly include PTFE and RPTFE. Suitable for strong corrosive media for various pressures at lower temperatures.
6.Asbestos-packing gasket
It is suitable for smooth flange sealing face, concave-convex flange sealing surface and tongue-and-groove sealing face. It’s of good corrosion resistance and thermal stability, good plasticity, and small sealing force to ensure sealing, but with low strength easy to stick on the flange sealing face. It is used in medium pressure valves with high temperature.
3.Graphite gasket coated with metal
It is made of spiral wound asbestos gaskets coated with thin metal, usually used in high temperature and pressure.
4.Spiral wound gasket
It is made of a mixture bind of corrugated metal and sealing materials, such as steel strip-asbestos, steel strip-PTFE, steel strip-flexible graphite, etc., suitable for high temperature and medium pressure valves.
5.PTFE gasket
Generally used for tongue-and-groove sealing face, mainly include PTFE and RPTFE. Suitable for strong corrosive media for various pressures at lower temperatures.
6.Asbestos-packing gasket
It is suitable for smooth flange sealing face, concave-convex flange sealing surface and tongue-and-groove sealing face. It’s of good corrosion resistance and thermal stability, good plasticity, and small sealing force to ensure sealing, but with low strength easy to stick on the flange sealing face. It is used in medium pressure valves with high temperature.
