Learn About Different Types Of Flange Faces.

Learn About Different Types Of Flange Faces.

A flange face is the surface area hosted by the gasket. There is a total of six different types of flange faces namely Flat (FF), Lap Joint, Tongue and Groove (T&G), Ring Joint (RTJ), & Male and Female (M&F). The different types of flange faces require a varying range of gaskets. Moreover, they are never advised to be mated to prevent the leakage of the joint. For flange facings such as FF and RF, there are different types of finish namely serrated, stock, and smooth.

Types of Flange Facings

According to the norms of ASME B16.47 and ASME B16.5, there are six major types of flange faces. Let us take a detailed look at each of these faces one by one:

  1. Flat Face Flange (FF)

In flat face flanges (FF), the surface of contact has the same height as that of the flange’s bolting line. Usually, only the soft type full-face gaskets are used between the two flat face flanges. Moreover, according to the ASME B31.3 norms, it’s never advised to mate a flat face flange with raised face flanges because the resulting joint will leak.

  1. Lap Joint Flange

As the name suggests, the lap joint has a flat surface that is not used to seal the joints of the flange but to host a stub end’s back. In fact, in the lap joint flange, the stub end itself has a sealing surface that can be either raised face or flat face.

  1. Male and Female Flanges (M and F)

With a great similarity to the groove and tongue flanges, both female and male flanges (M and F face type) match with each other as well. However, one of these flanges has an extra piece of the area beyond its face range, the male flange. On the other hand, the female flange has a matching area in depression machined on the surface of the facing. While the male face is around 1/4 inch higher, the female face is only around 3/16 inch deep only. But both of these faces have a very smooth finish and the female face’s outer diameter regains the gasket.

  1. Tongue and Groove Flange (T and G)

Two tongue and groove flanges act as a great couple because they fit into one another perfectly. One of these flanges has a raised ring and the other has a groove. Due to this, they can mate with ease and the tongue enters the groove to completely seal the joint. They are also standardized in both small and large types in the market.

  1. Raised Face Flange (RF)

As the gasket surface area of a raised face flange (RF) is placed above the bolting line of the flange, they are very easy to recognize. This type of flange face is also compatible with a great variety of flange gaskets that range from metallic types to semi-metallic types (For instance spiral wound gaskets and jacketed gaskets), either full-face or ring. The major benefit of having a design of a raised flange face is that it concentrates the pressure exerted by the two malting flanges on a completely small surface area that helps in increasing the strength of the seal. The raised face’s height depends upon the pressure rating of the flange as per the directions of ASME B16.5 for specifications of pressure classes 300 and 150, classes 2500 and 400, height 1/16 inch or 1.6 mm, and raised face height of 1/4 inch or 6.4 mm.

  1. Ring Joint Flanges (RTJ)

With a metal-to-metal seal created between the mating flanges, the ring joint type flanges are used only in high temperature and pressure conditions. These flange faces also have a host for metallic ring joint gaskets in the form of circular grooves. The force applied to bolt and tighten two RTJ flanges together deforms and compresses the metallic gasket located inside the groove to create an extremely subtle metal-to-metal seal. These flange faces can also be sealed easily with the help of different styles of RTJ gaskets such as R, BX, and RX and profiles such as oval and octagonal. Out of all these, the most common type of gasket is the R style that has an octagonal section.

Conclusion

With such a great variety of flange faces, you can always make sure you find the perfect match for your job. Knowing about the different types of flange facings will certainly help you in the long run.


Content Sources :- ABSgroup

Comments

Post a Comment

Popular posts from this blog

Hydraulic Bolt Tensioner: How It Works

Image
  For simpler and more accurate tightening of large-diameter stud and bolt assemblies, hydraulic bolt tensioners are mechanical fasteners that are utilized in place of normal bolts or hex nuts. Several bolt tensioners use manual or hydraulic techniques to apply torque. Devices that use hydraulics employ fluid force. Products that require manual power are turned using a hand tool such as a torque wrench . There are also hydraulic bolt tensioners that impart torque using different non-manual, non-hydraulic techniques. The greatest amount of rotating force that can be generated for all varieties of bolt tensioners is indicated by the torque rating. Thrust collar inner diameter and threaded diameter are additional crucial characteristics. To discover more about how hydraulic bolt tensioners operate, read the entire article. How does it work?  Large diameter bolts can be accurately and quickly tightened to high preloads using a hydraulic bolt tensioner . Like hydraulic torque wren...
Read more

All about Flange Facing and Its Advantages

Image
  When there is a pipeline or pipework, you will see flanges or welded joints made up of distinctive designs, sizes, and materials. A flange can be described as an internal or external ridge or a lip/rim that is carried out for strength. There can be an iron beam in the form of a T-beam or I-beam. There can also be a flange of an attachment to a different object such as a steam cylinder or on the ends of a pipeline etc. There is a lot of evidence that shows that in various pipeline systems, both flanges and valves can release hydrocarbons, and the piping ends up becoming the biggest contributor. Hence, a good flange-facing process and regular inspection can be a great solution to this problem.  Importance of Flange Protection When discussing the utility, oil, and gas industry, thread protection and pipe flange are two of the most important things. There is an issue of contamination when we talk about these industries. This contamination not only happens after or during the sto...
Read more

What is Flange Facing? Why is it an essential activity for a successful maintenance plan?

Image
  Your project's success depends on the security of your pipeline and the flanges that connect them together as it optimizes your production. You'll be a hero if you get the project completed within the stipulated time-frame correctly. If you get it wrong, your project will be delayed, your costs will go up, and your client will be unhappy.  What Is Flange Facing?  Machining on flange surfaces is known as flange facing . Regular repair and replacement of flanges is essential to preventing leaks and corrosion. In order to keep flanges attached to each other, these onsite services are needed.  Flange facing is a critical process in the natural gas, petrochemicals, refinery, pharmaceuticals, pipelines, food manufacturing, chemical, & power generation industries. The flange facing procedure is also used in the following industries for plant maintenance and shut-down:  Manufacturing of nuclear weapons  In the high-purity market  Defense of the Diesel...
Read more