Shared by JIS Marine valve Manufacturer.
RTFE reinforced ptfe
RTFE is a modified PTFE material. Although the friction coefficient of pure PTFE is very low (0.02~0.04), it has a great amount of wear. Moreover, due to its characteristics such as easy creep, poor mechanical properties, low bearing capacity and poor dimensional stability, PTFE has great limitations as a friction material. Modification, only to meet all walks of life by using the method of composite materials for the special requirements of wear-resistant sealing material is put forward, in terms of PTFE improve wear resistance, can be mixed with some wear-resisting material such as glass fiber, carbon fiber, graphite, molybdenum disulfide, bronze powder and some organic compounds, make them form a mesh in the PTFE layered structure nodes and improve the stiffness and creep resistance, thermal conductivity, and greatly improve the wear resistance.
Fluorine rubber Viton
The rated temperature of fluorine rubber seat is -18℃~150℃. Viton is a registered trademark of dupont and Fluorel is a registered trademark of 3M company. This material has high temperature resistance and excellent chemical corrosion resistance. Suitable for hydrocarbon products, low and high concentrations of mineral acids, but not for steam media and water (poor water resistance).
The rated temperature range of uhmwpe seat is -32℃~88℃. This material has better low temperature resistance than PTFE, but still has excellent chemical resistance. Uhmwpe also has good wear resistance and corrosion resistance, and can be used in high wear conditions.
Silicone of copper Silicone
Silicon-copper rubber is a polymer whose main chain is composed of silicon-oxygen atoms with organic groups. The rated temperature range is -100℃~300℃. It has good heat resistance and temperature resistance, excellent electrical insulation and large chemical inertia. Suitable for organic acids and inorganic acids with low concentration, dilute alkali and concentrated alkali. Disadvantages: low mechanical strength. Post-cure treatment is required.
Graphite is the crystal of carbon, is a non-metallic material, color silver gray, soft, with metallic luster. Mohs hardness is 1~2, the specific gravity is 2.2~2.3, and the bulk density is 1.5~1.8. With high temperature resistance, oxidation resistance, corrosion resistance, thermal shock resistance, strength, toughness, high self-lubrication strength, thermal conductivity, electrical conductivity and other unique physical and chemical properties. It has special oxidation resistance, self – lubricity and plasticity at high temperature. It can be used as filler or performance improver for rubber, plastic and various composite materials to improve the wear resistance, compression resistance or conductivity of materials. The gasket, packing and seat of valves are usually made of graphite.
Graphite of high melting point, to 3000 ℃ under the vacuum is to begin to soften tends to melt state, graphite evaporated sublimation to 3600 ℃, the general material under the high temperature strength decreases gradually, while the graphite in the heated to 2000 ℃, its strength is normal temperature double instead, but the difference of oxidation resistance of graphite oxidation rate was gradually increased with the temperature.
That’s all for the sharing, thanks for your reading, and we also supply JIS marine Check Valve for sale, if you have any demand for our products, just feel free to contact us.