Metal spiral wound gasket is a kind of sealing gasket widely used at present. It is the gasket with the best resilience among the semi-metallic gaskets. It is made of V-shaped or W-shaped thin steel strips alternately wound with various fillers. High temperature, high pressure and adapt to ultra-low temperature or vacuum conditions. By changing the material combination of the gasket, it can solve the chemical corrosion problem of various media on the gasket. The structure density can be made according to different locking force requirements. The main body and accurate positioning, the spiral wound gasket is equipped with a metal inner reinforcement ring and an outer positioning ring. The inner and outer steel rings are used to control the maximum compression degree, and the surface accuracy of the flange sealing surface contacted by the gasket is not high.
Graphite gasket:
The commonly used inner reinforcing materials for graphite composite gaskets are ss304, ss316 or tinplate, etc., with a thickness of 0.1~0.127mm, and the form of sprint plate reinforcement, mesh plate reinforcement, and flat plate reinforcement. The commonly used material is 304 reinforced graphite, which can be made into a variety of round geometric gaskets, which are widely used in pipelines, valves, pumps, pressure vessels, heat exchangers, condensers, generators, air compressors, and exhaust pipes. , Refrigerators, etc. Graphite reinforced gaskets can also be cut into gaskets with complex shapes, such as gaskets for water level gauges, punched flange gaskets and cylinder gaskets for automotive diesel engines.
Graphite composite gaskets can be processed into the following forms according to the needs of use: 1. Basic graphite composite gaskets 2. Graphite composite gaskets on the inner side of the package 3. Graphite composite gaskets on the outer side of the package 4. Graphite composite gaskets on the inner and outer sides. The edging form of graphite composite gasket not only maintains the excellent performance of the original gasket, but also is easy to install and disassemble, and is not easy to be damaged. At the same time, it can prevent the corrosion of the gasket by the medium and improve the pressure resistance. Commonly used edging material is 304 or 316 stainless steel.
1. Used as refractory material: Graphite and its products have the properties of high temperature resistance and high strength. It is mainly used in the metallurgical industry to make graphite crucibles. In steelmaking, graphite is often used as a protective agent for steel ingots and as an inner lining of metallurgical furnaces.
2. As a conductive material: used in the electrical industry to make electrodes, brushes, carbon rods, carbon tubes, positive electrodes of mercury positive current devices, graphite washers, telephone parts, coatings for television picture tubes, etc.
3. As a wear-resistant lubricating material: Graphite is often used as a lubricant in the machinery industry. Lubricating oil is often not used under high-speed, high-temperature, and high-pressure conditions, while graphite wear-resistant materials can work at high sliding speeds at a temperature of 200 to 2000 ℃ without lubricating oil. Many equipment that transports corrosive media widely use graphite materials to make piston cups, seals and bearings. They do not need to add lubricating oil when they are running. Graphite emulsion is also a good lubricant for many metal processing (wire drawing, pipe drawing).
4. Graphite has good chemical stability. Specially processed graphite, which has the characteristics of corrosion resistance, good thermal conductivity, and low permeability, is widely used in the production of heat exchangers, reaction tanks, condensers, combustion towers, absorption towers, coolers, heaters, and filters , Pump equipment. It is widely used in petrochemical industry, hydrometallurgy, acid-base production, synthetic fiber, papermaking and other industrial sectors, which can save a lot of metal materials.
5. Used as casting, sand-finding, die and high-temperature metallurgical materials: Because graphite has a small thermal expansion coefficient and can withstand rapid cold and rapid heat changes, it can be used as a glass mold. After graphite is used, ferrous metals can be used to obtain castings with precise dimensions and a high surface smoothness and yield. It can be used without processing or a little processing, thus saving a lot of metal. The production of cemented carbide and other powder metallurgy processes usually use graphite materials to make porcelain boats for compression molds and sintering. Single crystal silicon crystal growth crucibles, regional refining vessels, support fixtures, induction heaters, etc. are all made of high-purity graphite. In addition, graphite can also be used for vacuum smelting graphite heat insulation boards and bases, high-temperature resistance furnace tubes, rods, plates, grid sheds and other components.
6. Used in the atomic energy industry and national defense industry: Graphite has a good neutron moderator used in atomic reactors. Uranium-graphite reactors are currently the most widely used type of atomic reactors. The deceleration material in the nuclear reactor used as power should have a high melting point, stability, and corrosion resistance. Graphite can fully meet the above requirements. The purity of graphite used in atomic reactors is very high, and the impurity content should not exceed dozens of PPM. Especially the boron content should be less than 0.5PPM. In the national defense industry, graphite is also used to make solid fuel rocket nozzles, missile nose cones, parts of aerospace equipment, heat insulation materials and radiation protection materials.
7. Graphite can also prevent boiler fouling. Tests by related units have shown that adding a certain amount of graphite powder (approximately 4 to 5 grams per ton of water) can prevent boiler surface fouling. In addition, graphite coating on metal chimneys, roofs, bridges, and pipes can prevent corrosion and rust.
8. Graphite can be used as pencil lead, pigment and polishing agent. After the graphite has been specially processed, various special materials can be made for use in relevant industrial sectors
