What are the non-metallic gaskets?

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1. What are the types of gaskets? Gaskets are made from metallic, semimetallic, and non-metallic sheet materials through processes such as cutting, stamping, or trimming; they are used to achieve a sealed connection between pipes, as well as between various components of machinery and equipment. Based on material, they can be divided into three main categories: non-metallic, semimetallic, and metallic gaskets. Due to the soft texture and corrosion resistance of non-metallic materials, semimetal gaskets are commonly used for flange sealing in medium and low-pressure vessels or pipelines at normal and moderate temperatures. 2. What are the commonly used non-metallic gaskets? Commonly used non-metallic gaskets mainly include rubber gaskets, asbestos gaskets, asbestos-rubber gaskets, flexible graphite gaskets, and polytetrafluoroethylene gaskets. ① Rubber pad. The main materials used to manufacture rubber gasket sheets include natural rubber, nitrile rubber, neoprene, etc. In addition, special rubbers such as fluororubber are also beginning to be used. Rubber is widely used for sealing containers and pipes due to its dense structure, soft texture, good elasticity, ease of being cut into various shapes, as well as its low cost and availability. However, it cannot withstand high pressures, dissolves and swells in mineral oils, is not resistant to corrosion, and loses its elasticity when exposed to high temperatures. ②Asbestos pad. Asbestos materials come in two types: chrysotile and blue asbestos. The normal operating temperature for asbestos boards is below 550 degrees; for low-pressure vessels with larger diameters, asbestos tape or asbestos rope can be used. However, asbestos products are mostly classified as carcinogens internationally, and their use is generally not recommended. ③ Asbestos rubber gasket. Asbestos rubber gaskets are made by compressing asbestos, rubber, and fillers. Based on their manufacturing processes, properties, and applications, they are further divided into high-pressure asbestos rubber sheets, medium and low-pressure asbestos rubber sheets, and oil-resistant asbestos rubber sheets. ④ Flexible graphite gasket. Flexible graphite is a novel sealing material with excellent resilience, flexibility, and heat resistance, and it has been rapidly adopted and used in chemical industries. ⑤ Polytetrafluoroethylene gasket. Polytetrafluoroethylene (abbreviated as PTFE) is known as the \"king of plastics\" because its chemical resistance, heat resistance, cold resistance, and oil resistance surpass those of any other plastic currently available. It does not age easily, does not burn, and has almost zero water absorption. It has a dense structure and a non-polar molecular structure; it is used as a gasket, allowing the contact surface to remain flat and smooth, without sticking to metal flanges. Apart from being eroded by molten alkali metals and fluorine-containing gas, it can resist corrosion by a variety of acid, alkali, salt, and oily solution media. The content contained herein is sourced from the Internet; the copyright of the reproduced materials belongs to their original authors and institutions. If there is any infringement, please contact us to have it removed.