| 摘要 |
PURPOSE:To prevent a sealing function from degradation even in the repetition of high-low temperature cycle in a fluid sealing member such as a ball valve by forming an annular slide contact member of a non-penetration property carbon material made from raw material of mesocarbon micro beads. CONSTITUTION:An annular slide contact member A2 and an annular contact seal member B3 seal a valve body 1 from a valve box 5. Said member A is made from raw material of mesocarbon micro beads (MCMB) crushed, molded and sintered into granules having average diameter of 10 mum or less and if necessary graphitized. Thus, said member A has the non-penetration property against fluid and the chemical resisting property, small coefficient of thermal expansion, large mechanical strength and further self-lubricating property to provide the most suitable material capable of resisting the wide range from extremely low temperature to high temperature. Thus, it is neither broken by the thermal expansion difference between impregnated material or mixture and carbon material even by the repetition of extrenely low temperature and high temperature, nor degraded in the effluece of impregnated component due to corrosive chemicals and the sealing function so that a satisfactory sealing property can be maintained for a long time. |
