Stainless Steel Flanges are important parts used in many piping systems. They help connect pipes, valves, pumps, and other equipment to form a strong and leak-proof system. These flanges also make it easier to repair or inspect the pipes when needed. There are different types and grades of stainless steel flanges, each made for specific uses.
Let’s understand the different types of stainless steel flanges and their common materials.
Types of Stainless Steel Flanges
1. Weld Neck Flange
This flange has a long neck that is welded to the pipe. It gives strong support and handles high pressure and temperature well. Weld neck flanges are commonly used in critical systems.
2. Slip-On Flange
A slip-on flange is easy to install. It slides over the pipe and is welded from both inside and outside. These flanges are perfect for low-pressure systems.
3. Blind Flange
Blind flanges are used to close the end of a pipe or valve. They are useful when you need to block off a section of pipe for inspection or repair.
4. Threaded Flange
Threaded flanges have internal threads that match the external threads of a pipe. These flanges do not need welding and are used in low-pressure and non-critical systems.
5. Socket Weld Flange
This type has a socket where the pipe is inserted and then welded. It is used for small pipes in high-pressure systems. It also gives a strong and smooth connection.
6. Lap Joint Flange
Lap joint flanges are used with a stub end. They are useful for systems that need to be taken apart often. These flanges help in easy alignment and fitting.
7. Ring-Type Joint (RTJ) Flange
RTJ flanges are used in high-pressure and high-temperature systems. They have a special groove for a metal ring gasket, which gives a strong seal.
8. Orifice Flange
Orifice flanges are used to measure the flow of liquids or gases in a pipeline. They come with holes to connect instruments for flow measurement.
Common Grades of Stainless Steel Flanges
Stainless steel flanges are made in different grades based on where they are used. Here are some common ones:
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304 / 304L: These are widely used for general purposes. Grade 304L has low carbon, which makes it easier to weld.
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316 / 316L: These contain molybdenum, which gives better resistance to corrosion, especially in marine or chemical environments.
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310 / 310S: These grades are good for high-temperature applications like furnaces and heat exchangers.
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321 / 347: These are stabilized stainless steels that resist corrosion at high temperatures.
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904L: A high-alloy grade that works well in harsh environments, including areas with sulfuric acid.
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Duplex Stainless Steel (e.g., 2205): These are strong and resist stress corrosion. They are used in industries like oil, gas, and chemical processing.
Conclusion
Choosing the right type and grade of stainless steel flanges is important for safety and long life of piping systems. Factors like pressure, temperature, and environment should be considered before selecting the flange. With many options available, understanding the basic types and materials helps in making the best choice for your project.
