Material analysis of sealing ring

Material analysis of sealing ring What are the sealing ring materials, and what are their advantages and disadvantages? The melting point of PTFE is 327°C, the relative density is 2.18-2.3g/cm3, the Shore film hardness is D50-65, and it has good physical and chemical stability and self-lubrication. The category with the largest total number has good overall performance, such as: high and low temperature resistance, corrosion resistance, aging resistance, non-adhesion, high insulating layer, high moisturization, and no harmful substances. However, polytetrafluoroethylene has poor stress relaxation resistance, poor wear resistance and large product expansion coefficient, so this defect is usually improved by filling and modifying materials. Common filling materials include copper scraps, carbon fiber materials, glass fiber, high-purity graphite, molybdenum disulfide, polystyrene ester, polyether ether ketone, etc., according to different situations and main purposes, one or more types can be filled. Chemical material. PTFE has“Internal cooling”. That is, the plastic deformation (stress relaxation) of the raw material product under the effect of continuous load for a long time, which imposes certain restrictions on its use. For example, when PTFE is used as a sealing gasket, the anchor bolts are tightened too tightly for tight sealing, so as to exceed the special reduction internal stress, the gasket will cause damage to the gasket.“Internal cooling”(stress relaxation) and squashed. This defect can be eliminated by adding appropriate fillers and improving part construction. PTFE has outstanding non-stickiness, which limits its application in industrial production. It is a very good decollagen material, and these properties make it extremely difficult to bond to the surface of other items. The thermal expansion coefficient of PTFE is 10~20 times that of steel, which is larger than that of most plastics, and its thermal expansion coefficient changes very irregularly with the change of temperature. When using PTFE, if insufficient attention is paid to this characteristic, it is very easy to cause damage. By filling the PTFE seal with carbon fiber material modified material, the compressive capacity, wear resistance, thermal deformation resistance and compressive strength have been greatly improved. At the same time, the hardness of the product has been enhanced, which is suitable for rotating Seal, usually used to make torsion spring energy storage pan plug seal, vehicle wave box oil ring, etc. Carbon fiber materials are likely to be oxidized and decomposed in a strong alkali environment, so it is not recommended to be used in strong alkali working conditions. By filling the PTFE hydraulic press seal with glass fiber modified material, the compressive capacity, wear resistance, thermal deformation resistance and compressive strength have been greatly improved. At the same time, the hardness of the product has been enhanced. Rotary seals are usually used to make gaskets, torsion spring energy storage pan plug seals, vehicle gearbox oil rings, etc. Glass fiber is likely to dissolve in acidic conditions, so it is not recommended for use in working conditions containing alkali or water content.