What are the Types of Flange?

Flanges are very critical piping system fittings. Flanges link pipes, valves, pumps, and other hardware so that the system operates leak-free and in a safe manner. There are various types of flanges, and each of them is specified for particular use, pressure levels, and designs to meet particular projects' needs. The below is a complete list of flange types explaining what makes them unique and for what purpose they are utilized:

1. Weld Neck Flange (WN)

• Description: These flanges have a tapered long hub which is welded onto the pipe. This is an excellent design for minimizing stress concentration at the flange base.
  
  

• Application: Applicable to high-temperature and high-pressure applications, for example, in the oil and gas sector.
  
  

• Advantages:

  • Excellent strength and resistance to mechanical stress.

  • Provides a seamless connection, enhancing durability.

2. Slip-On Flange (SO)

• Description: This flange is placed over the pipe and welded on the inside and outside to make it sturdy.

  • Application: Typically applied in low-temperature and low-pressure applications.
    
    

• Advantages:

  • Easy to install and align.

  • Less expensive than weld neck flanges.

3. Socket Weld Flange (SW)

• Description: The pipe is fitted into a socket inside the flange, and then the flange is welded from the outside.
  
  

• Application: Often used for high-pressure, low-diameter piping systems.
  
  

• Advantages:

  • Offers a safe and watertight connection.

  • Extremely well adapted to conduits with pressurized liquid flow.

4. Threaded Flange

• Description: This flange has threads inside the bore, allowing it to be screwed onto a pipe without welding.
  
  

• Application: Used in low-pressure systems and applications where welding is not feasible (e.g., explosive environments).
  
  

• Advantages:

  • Easy to install and remove.

  • Does not require welding, making it suitable for specific situations.

5. Blind Flange

• Description: A solid, round flange without a bore, used to block off the end of a piping system.
  
  

• Application: Often employed for testing and maintenance purposes to isolate a section of the pipeline.
  
  

• Advantages:

  • Excellent for pressure testing.

  • Provides a robust seal to prevent leakage.

6. Lap Joint Flange (LJ)

• Description: This flange is used with a stub end, where the flange is free to rotate around the pipe.
  
  

• Application: Common in systems requiring frequent dismantling, such as in food processing or water treatment plants.
  
  

• Advantages:

  • Easy alignment during installation.

  • Cost-effective for low-pressure systems.

7. Ring Type Joint Flange (RTJ)

• Description: Features a groove that holds a metal ring, which is compressed to form a strong seal.
  
  

• Application: Used in high-pressure, high-temperature environments, such as refineries and chemical plants.
  
  

• Advantages:

  • Provides a leak-proof seal under extreme conditions.

  • Resilient against mechanical stress.

8. Orifice Flange

• Description: Designed with pressure taps, it is used in conjunction with an orifice plate to measure the flow rate of fluids.
  
  

• Application: Found in flow metering systems in industries like oil, gas, and water treatment.
  
  

• Advantages:

  • Facilitates precise fluid flow measurement.

  • Suitable for demanding industrial settings.

9. Long Weld Neck Flange

• Description: Similar to a weld neck flange but with an extended neck, used where reinforcement is necessary.
  
  

• Application: Commonly found in pressure vessels, columns, and heat exchangers.
  
  

• Advantages:

  • Adds structural integrity to the connection.

  • Handles extreme temperatures and pressures effectively.

10. Reducing Flange

• Description: Used to connect pipes of different diameters.
  
  

• Application: Common in systems requiring size transitions, such as in pumping stations.
  
  

• Advantages:

  • Eliminates the need for separate reducers.

  • Maintains a compact design.

Each unique type of flange possesses a series of distinct characteristics that are specifically designed to meet a sequence of performance requirements. Determination of the appropriate flange is based on several critical factors such as system pressure, temperature ranges, fluid type transported, and the frequency of need for periodic maintenance or potential disassembly. Through awareness of these different types of flanges, various industries can appropriately guarantee not only safe but also efficient operation of their pipeline systems. If you are interested, please let me know, and we can go further to discuss other important factors of piping systems!

good information.

Thanks a lot