Expanded graphite, also known as flexible graphite, is made from high quality flake graphite modified by chemical treatment and high temperature instantaneous expansion. It can be machined to all kinds of sealing products. It not only maintains the excellent chemical properties of natural graphite, but also increases a lot of unique mechanical properties. It is a kind of ideal sealing material with wide application range and strong sealing ability. The main performance is as follows:

1. Physical and chemical properties:

1, density: the bulk density of flake graphite is 1.08g/cm3, and the bulk density of expanded graphite is 0.002 to 0.005g/cm3, and the product density is 0.8 ~ 1.8g/cm3. Therefore, the quality of expanded graphite is light and plastic.

2, purity: fixed carbon content is about 98%, or even more than 99%, enough to meet the requirements of high purity seals in atomic energy, aerospace and other industrial sectors.

3, temperature: theoretically, the expanded graphite can withstand 200 C to 3000 C.  As the packing seal, in - 200 C ~ 800 C safe use. It has excellent properties such as low temperature, no brittleness, no aging, high temperature, no softening, no deformation and no decomposition.

4, corrosion resistance: with chemical inertness, in addition to strong oxidants such as water, nitric acid, sulfuric acid and halogen, some specific temperatures, can adapt to the acid, alkali, salt solution, sea water, steam organic solvents and most of the medium;

5. The excellent thermal conductivity and the smaller thermal expansion coefficient are close to the same order of magnitude of the dual part material of the general sealing device, and can be well sealed in the conditions of high temperature, deep cooling and temperature upheaval.

6, resistance to radioactivity: neutron irradiation, gamma rays, alpha rays, beta rays and other long-term exposure without significant changes.

7, impermeability: gas and liquid have good impermeability. Because the surface of expanded graphite is very large, it is easy to form a thin layer of gas film or liquid film to prevent medium penetration.

8, self lubrication: Expanded Graphite still maintains hexagonal plane layer structure, and the surface layer is easy to slide and produce self lubrication under external force, which can effectively prevent the wear of shaft or stem.

Two. Mechanical properties:

1, softness: hardness is very low, it can be cut with ordinary tools, and it can be winded and bent arbitrarily.

2, high compressibility and resilience: expanded graphite products, the microcosmic still has many compressible closed small spaces, under the external force can be compressed, and at the same time, the air in the small space produces tension and resilience.