A flange is a ridged fitting that increases a pipe or tube’s connection strength. Generally, it is used in pipeline works to make the system more rigid and stable. A flange plays a significant role in a variety of industries. Using different kinds of flanges can help you prevent the escape of gas, air or water, and any other fluids that are readily available in an industrial and commercial situation. Flanges are of different types and material grades and are used for various conditions and purposes. Here are the most common types of flanges used in pipeline projects:
Flat Face Flanges: The Flat-Face flanges have gasket surfaces in a similar plane as the flanges for the bolting circle face. Flat face flanges are almost never to be bolted to a raised face flange but should be connected to other flat face flanges, usually with flat face gaskets. Some old flanged fittings are made from cast iron, although this is a less common material for pressurized applications these days.
Raised Face Flanges: The most common type of flange used in process plant applications is the Raised Face Flange. You can also identify it quickly at the connection point. The reason behind the name “Raised Face” is that the gasket surfaces are raised above the bolting circle face. This face type allows using a comprehensive combination of gasket designs, including flat ring sheet types and metallic composites such as spiral wound and double jacketed types.
Ring Type Joint Flanges: The Ring Type Joint Flanges are commonly used in high pressure and high-temperature services above 800°F (427°C). They have grooves cut into their faces with steel ring gaskets. The flanges seal when tightened bolts compress the gasket between the flanges into the grooves, deforming (or Coining) the gasket to make intimate contact inside the grooves, creating a metal to metal seal. Gasket materials are almost always steel or alloy. API specifications require these seal types for all flanges (B and BX ring grooves.)
Tongue & Groove Face Flanges: The Tongue and Groove faces of alternate flanges must be correlated. One flange face has a raised ring (Tongue) machined onto the flange face, while the mating flange has a matching depression (Groove) machined into its face. Tongue-and-groove facings are standardized in both large and small types.
Male & Female Face Flanges: With the male and female types, the flanges also must be matched. One flange face has an area extending beyond the regular flange face (Male). On the other side, the female flange or mating flange has a matching depression similar to its face. The female face’s depth is 3/16 inches, and the male face’s height is 1/4 inches, and both are smooth finished. The outer diameter of the female face acts to locate and retain the gasket. There are two versions available – the Small Male & Female Flanges and the Large Male & Female Flanges. Custom male and female facings are commonly found on the Heat Exchanger shell to channel and cover flanges.
So if you are confused about how to choose the perfect flanges type for your particular projects, here are some tips for you:
1. First, you need to learn the configuration of your flange and its process of application. The main issue here is to choose the right flange instead of just defaulting to a simple flat face or raised face configuration slip-on. It will guarantee you that you will be able to prevent some stressful reworking of your pipeline assembly.
2. You need to study and identify the proper detail regarding your flange to secure your connections. This way, you can locate and select the right shape and flange material for your project. You will find it once you are well aware of the media flowing through your pipeline or vessel.
3. Now you have to choose the best alloy type for your project. Since most of these products are often made from different materials, you need to select which material grades you want. Your choices include flange types made from non-metallic, metallic, elastomeric materials, and fibrous.
4. In the next step, you need to evaluate the chemical resistance and corrosion requirements of the flanges to be installed. After you consider the materials, you also need to understand their chemical resistance levels by alloy. It ensures that you will adhere to the specific requirements of your application to suit your project demands.
5. Be sure to find a professional who can guide you properly. Often this is a member of your own staff. This helps to ensure the safety and practicality of your flanged assembly. A well-trained engineer will provide you with the correct information you need and work with you properly to apply the best fitting in the right service. By performing accurate testing and review of your design calculations, you will reliably test the performance of your entire assembly.
6. The next step is to choose the proper manufacturer. To provide you with the best flange that you are looking for, you should find the most reliable, reputable, and qualified manufacturer.
By following all these tips, you will find the perfect match of the flange for your project and have a better decision regarding your many options.
Understand the situation in its entirety and choose the right flange type for your pipeline project.