The main performance of Spherical Graphite
Spherical Graphite, also known as flexible graphite, is a high-quality flake graphite by chemical treatment, high temperature instantaneous expansion modified. Can be machined into a variety of sealing products. It not only retains the natural chemical properties of natural graphite, but also adds many unique mechanical properties, is a wide range of applications, sealing the ideal sealing material. The main performance is described as follows:
First, physical and chemical properties:
1, density: the bulk density of the flake graphite is 1.08 g / cm3, the Spherical Graphite has a bulk density of 0.002 to 0.005 g / cm3, and the product density is 0.8 to 1.8 g / cm3. So the Spherical Graphite material quality is light and plastic;
2, purity: fixed carbon content of about 98%, or even more than 99%, enough to meet the atomic energy, aerospace and other industrial sectors in the high-purity seal requirements;
3, temperature: theoretically, Spherical Graphite can withstand -200C to 3000C. As a packing seal, can be used in -200C ~ 800CC safe use. With low temperature is not brittle, not aging, high temperature does not soften, no deformation, no decomposition of the excellent performance;
4, corrosion resistance: with a chemical inert, in addition to strong oxidants such as aqua regia, nitric acid, sulfuric acid and halogen some specific temperature, can adapt to acid, alkali, salt solution, sea water, steam organic solvents and other media;
5, excellent thermal conductivity and a small coefficient of thermal expansion, the parameters close to the general seal device on the same order of the same material, in the high temperature, cryogenic and temperature drastic conditions can also be a good seal;
6, radioactivity: by neutron rays, γ-ray, α-ray, β-ray and other long-term exposure without significant changes;
7, impermeability: the gas and liquid has a good impermeability. Because the spherical surface of the graphite can be large, easy to form a layer of thin film or liquid film to prevent media penetration;
8, self-lubricating: Spherical Graphite still maintain a hexagonal planar structure, external force between the plane layer is relatively easy to slide between the self-lubricating, effectively prevent the shaft or stem wear.
Second, the mechanical properties:
1, softness: hardness is very low, with ordinary tools can be cut, and any winding, bending;
2, high compressibility and resilience: Spherical Graphite products, there are still a number of micro-compressible closed small gap, external force can be compressed, at the same time, due to the small gap in the air tension and resilience.
Spherical Graphite is a good performance of the adsorbent, in particular, it has a loose porous structure, the organic compounds with a strong adsorption capacity, 1 g Spherical Graphite can absorb 80 g of oil, so Spherical Graphite was designed as a variety of industrial grease and Industrial oil adsorbents. Spherical Graphite is very easy to adsorb oil, organic molecules and hydrophobic substances for water environmental treatment with other substances irreplaceable effect. When it is used in granular form for the surface of oil, according to the size of the surface oil and oil types of different, the amount of 1 ~ lo% / rn, adsorption time can be 15rain to several h range.
Compared with other adsorbents, Spherical Graphite has many advantages. Such as cotton, grass ash, polypropylene fiber, perlite, vermiculite, etc., which are used in the presence of some of the adsorbents, such as cotton, grass ash, polypropylene fiber, vermiculite, etc. It is difficult to deal with the post-treatment; the adsorption of the Spherical Graphite on the oil is large, the oil is floated on the surface of the water, the fishing is easy to be recycled, and the recycling is easy to use. It can be extruded, centrifuged, vibrated and solvent Cleaning, burning, heating extraction and other methods, and will not form secondary pollution.