A look at the common features you should consider when picking a flange for your piping arrangement.
WHAT ARE FLANGES AND HOW DO THEY WORK?
Offering a consistent way to connect pipe systems with different equipment, valves, and other components of effectively any processing system, flanges are the second most used joining technique after welding.
when maintaining piping systems flanges enhances flexibility by allowing for easier disassembly and better access to system components.
A normal flanged connection comprises of three parts:
- Gasket
- Pipe Flanges
- Bolting
In most scenarios, there are particular gasket and bolting materials made from the same, or permitted materials as the piping components you wish to connect. Stainless Steel flanges are some of the most common. However, flanges are offered in an extensive range of materials so matching them with your requirements is essential.
Other common flange materials include Inconel, Monel, Chrome Moly, and many others depending on the application.
The best choice for your needs will depend on both the system in which you plan to use the flange and your specific requirements.
MOST COMMON FLANGE TYPES AND CHARACTERISTICS
Flanges are not a one-type-fits-all sort of solution. Sizing apart, matching the perfect flange design to your piping system and intended usage will help to ensure consistent operation, a long service life, and optimal rating.
Here’s a look at the most common types of flange available.
Perfect for smaller pipe diameters in low-pressure scenarios and low-temperature, socket-weld flanges feature a connection in which you set the pipe into the flange and then secure the connection with a particular multi-pass fillet weld. This makes this style simpler to install than other welded flange types while escaping the limits associated with threaded ends.
Also known as a screwed flange, this type has a thread inside the flange bore which fits with the matching male thread on the pipe or fitting. The threaded joining means you can avoid welding in many use situations. Just match the threading to the pipes you wish to connect.
Featuring a two-piece design, lap joint flanges need butt welding of the stub end to the pipe or fitting with the use of a backing flange to form the flanged connection. This design makes this style prevalent for use in systems with restricted physical space or systems which need frequent disassembling and maintenance.
Slip-on flanges are very common and are offered in a huge range of sizes to accommodate systems with higher flow rates and throughput. Just match the flange to the outer diameter of the pipe you aim to connect. Installation is slightly more technical as you’ll need fillet weld both sides to secure the flange to the pipe.
Like lap joint flanges, weld neck flanges need butt welding for installation. Though, their integrity, performance in systems with several repeat bends, and the capacity to use them in high-pressure and high-temperature systems make them a primary choice for process piping.
Used for dismissing or isolating piping systems, blind flanges are basically boltable blank discs. When installed correctly and combined with the right gaskets, they can achieve an exceptional seal which is easy to remove when required.
FLANGE FACING TYPES
Flange design is just the start when considering the perfect flange for your piping system. Face types are another characteristic that will have a major influence on the ultimate performance and service life of your flanges.
Facing types define both the gaskets required to install the flange and features related to the seal created.
Common face types contain:
- Raised Face (RF): These flanges feature a minor raised section around the bore with an inside bore circle gasket.
- Flat Face (FF): As the name recommends, flat face flanges feature a plane, smooth surface combined with a full face gasket that contacts most of the flange surface.
- Tongue and Groove (T&G): These flanges feature matching grooves and raised sections. This aids in installation as the design helps the flanges to self-align and provides a reservoir for gasket adhesive.
- Ring Joint Face (RTJ): Used in high-pressure and high-temperature processes, this face type features a groove in which a metal gasket gathers to maintain the seal.
- Male & Female (M&F): Similar to tongue and groove flanges, these flanges use a similar pair of grooves and raised sections to protect the gasket. However, unlike tongue and groove flanges, these recall the gasket on the female face, providing more precise placement and increased gasket material options.
Many face kinds also offer one of two finishes: smooth or serrated.
Choosing between the choices is essential as they will determine the best gasket for a reliable seal.
In common, serrated faces help to produce stronger seals with soft material gaskets while smooth faces work best with metallic gaskets.
Materials used for Manufacturing Flanges
Flanges are manufactured from a variety of materials, grades. There are some materials that can be used to make Flanges. The most frequently used materials for Flange manufacturing are High Yield Carbon Steel, Carbon Steel, Alloy Steel, Stainless Steel, Duplex and Super Duplex, and different Nickel Alloy Grades such as Inconel, Monel and Hastelloy.
Conclusion
This guide offers a firm foundation of the basics of flange design and how to pick the perfect flange for your piping system. However, with an extensive range of stainless steel flanges and other flange materials available, it is difficult to list every configuration, detail, or consideration.Should you have questions, the Technical Sales Experts at Pearl Overseas are ready to help. Serving industries and businesses across Several countries since 2015, we understand the complexities of alloy piping and the requirements of your industry. Call or email us for further information and to find the perfect flange, piping, and components for your next project.
