Raw material and design scheme of plastic sealing ring

In the manufacturing industries of crude oil, chemical plants, machinery and equipment, when the temperature is low or high, the working pressure is high, and the corrosion energy is strong, the silicone sealing ring cannot be used. At this time, the use of plastic sealing rings can be considered. 1. Plastic sealing ring material Plastic sealing ring is often made of raw materials such as ptfe or polyester. The key to forming method is milling or die forming. Plastics such as ptfe (abbreviated as F4) and polyester have poor ductility and high strength, and are not suitable as raw materials for forming fillers compared to vulcanized rubber and leather products. However, it is ingenious, and it is still used in some places because of its many high-quality features. Taking ptfe sealing ring as an example, it has the advantages of excellent organic chemical reliability, swelling resistance and self-wetting, good high temperature and cold resistance, wear resistance and impact resistance, and very low friction resistance. However, because of its large linear expansion coefficient (about 7 times that of steel), poor heat transfer capacity (about 3/100 of steel), poor physical properties and cold flow conditions, it is stipulated that it must be dealt with in the design scheme. Precise manipulation of the pre-compression rate of the f4 seal and reasonable release of frictional heat are two key challenges. 2. Design scheme of plastic sealing ring The key to the design scheme of plastic sealing ring is to improve the material characteristics of the sealing ring and update the overall design. The key to improving the characteristics of plastics is to use filling plastics, modified engineering plastics, and composite plastics. Such as F4 contract F2 and other blended modified materials. F4 can be combined with vulcanized rubber cat to form a composite plastic. F4 is filled with glass fiber, glass powder, porcelain powder, etc. It can improve wear resistance, compressive ability and reduce shrinkage. Adding brass, molybdenum, silver and other powders can improve heat transfer and physical properties. Filling high-purity graphite and disulfide rubber pliers can improve heat transfer and wear resistance.