1. Oil and Gas Industry: This is one of the most widely used and demanding sectors for flanges. From oil and gas field exploration and extraction, long-distance pipeline transportation (submarine or onshore), to various refinery units (such as atmospheric and vacuum distillation, catalytic cracking, and hydrorefining), and liquefied natural gas receiving terminals, flanges of various pressure ratings, materials, and sealing surface types are extensively used to connect pipelines, valves, reactors, storage tanks, and equipment. They are diverse and capable of withstanding high pressure, high temperature, low temperature, and corrosive media.
2. Chemical and Petrochemical Industry: Chemical production processes involve a wide variety of chemicals, many of which are highly corrosive, toxic, or flammable and explosive. Chemical piping systems place extremely high demands on the sealing performance and corrosion resistance of flanges. Flanges are widely used to connect reactors, towers, heat exchangers, pumps, and process piping to ensure the airtightness and safety of the production process.
3. Power Industry: In thermal power plants, flanges are used to connect steam pipelines, feedwater pipelines, and fuel transport pipelines in boiler systems. These pipelines typically transport high-temperature, high-pressure steam and water, placing stringent requirements on the strength and sealing performance of flanges. In nuclear power plants, the requirements for flange safety, reliability, and material properties are even more advanced.
4. Water Supply and Drainage & Sewage Treatment: Flanges are widely used for connections between structures and pipelines in urban water supply networks, building internal water supply systems, and sewage treatment plants. Although the operating pressure and temperature are usually not high, the sheer volume of flanges and the need to ensure the hygiene and safety of water supply and prevent sewage leakage make them critical components.
5. Shipbuilding and Marine Engineering: Flanges are extensively used in ship propulsion systems (such as main engines and boilers), bilge piping, ballast systems, and fire protection systems. On offshore platforms, flanges are used to connect subsea pipelines, platform process equipment, and utilities, and must withstand the corrosion and complex mechanical loads of the marine environment.
6. Food and Pharmaceutical Industries: These industries have extremely high hygiene requirements and typically use stainless steel flanges with special sanitary designs (such as quick-connect flanges and aseptic flanges) to ensure smooth, seamless connections that are easy to clean and disinfect, preventing microbial growth. 7. Heating, Ventilation and Air Conditioning Systems: In the central air conditioning systems of large buildings, flanges are used to connect equipment such as air ducts, chillers, cooling towers, and water pumps, facilitating system installation and subsequent maintenance.
