Cold knowledge of seals: application matters of carbon graphite seals

The seals made of carbon graphite materials have the common advantages of metal materials and non-metal materials. Its material properties have excellent self-lubrication, chemical stability, high thermal conductivity, high temperature resistance, corrosion resistance, high wear resistance, low expansion, and easy processing. These properties of carbon graphite are necessary for pure water hydraulic sealing materials. Therefore, carbon graphite seals are essential sealing elements in pure water hydraulic systems;

Characteristic analysis of carbon graphite seals:

1. Thermal properties of materials: Carbon-graphite materials have high thermal conductivity and low expansion, and their thermal conductivity is second only to aluminum and copper. It is the only non-metallic material with high thermal conductivity. It can effectively keep the sealing surface in shape and avoid the problem of medium leakage caused by thermal deformation.

2. The chemical properties of the material: carbon graphite material is an inert material, the chemical properties are temperature and non-toxic, it has strong chemical stability in the air and 400 degrees Celsius, and has good corrosion resistance;

3. Mechanical properties of materials: carbon graphite materials are brittle materials with high compressive strength, low tensile strength and shear strength, and poor impact resistance, but they can be processed into any complex shape , has good machinability.

4. Water solubility and lubricity of materials: carbon-graphite materials have a small friction coefficient and excellent self-lubricating properties. Graphite lubricators are even better when they rely on other media. Graphite can be used in the presence of steam and air. It can better play lubricity, because the existence of water and air is the adsorption of water and gas molecules on the working surface of graphite, which increases the distance between the cleavage surfaces that slide with each other and weakens the binding force between them.


In addition: Graphite material also has a characteristic, it has strong adhesion with most metal materials, so graphite can easily form a graphite film on the friction pair of the anti-friction metal material; The friction between the two, thereby greatly reducing the friction factor and wear.



The above are some common application knowledge of carbon-graphite seals. For seals made of carbon-graphite materials, if you have a clear understanding of their material properties, you can use them with confidence.