Introduction to flanges, classification of flanges, types of flange sealing, etc
Thread Content
A flange, also known as a flange plate or collar connection, is an important method of connection in pipeline construction. Flange connection involves first fixing two pipes, fittings, or components to separate flanges. A gasket is placed between the sealing surfaces of the two flanges. The flanges have holes; the diameter of these holes and the number of bolts required vary depending on the pressure and diameter. Bolts are inserted into these holes, and after the nuts are tightened, the pressure on the surface of the gasket reaches a certain level, causing it to deform and fill in any unevenities on the sealing surfaces. This ensures that the two flanges are tightly connected, resulting in a leak-free seal. Some fittings and equipment already come with flanges, and they also belong to the flange connection type. Flange connection is a detachable type of connection; it is easy to use and capable of withstanding high pressures. Flange connections are widely used in industrial pipelines. There are four types of flange sealing surfaces: flat-sealing surface flanges (FF, RF), which are suitable for applications with low pressure and non-toxic media ； Rough-faced sealing flange (MFM), suitable for applications with slightly higher pressures ； Tongue-and-groove sealed face flange (T-G), suitable for flammable, explosive, toxic media and high-pressure applications. Ring joint face flange (RJ); flanges are classified by material into iron flanges, carbon steel flanges, stainless steel flanges, alloy steel flanges, copper flanges, etc. Flanges can be divided into vessel flanges and pipe flanges according to the components they connect. Flanges can be classified into cast flanges and forged flanges according to the manufacturing process. Flanges are classified into threaded flanges (screw flanges) and welded flanges based on the method of connection to the pipeline. For low-pressure, small-diameter threaded flanges (DN15-150), welded flanges are used for high-pressure and low-pressure large-diameter flanges. The thickness of the flanges, as well as the diameter of the bolt holes and the number of bolts, vary depending on the pressure and diameter. Flanges can be classified by structure type into flat welding flanges, butt welding flanges, socket welding flanges, integral flanges, loose-flange types, and threaded flanges, among others. Common flanges include flat welding flanges and butt welding flanges. Flat welding flanges have poor rigidity and are suitable for applications with a pressure of p≤4.0MPa ； Butt weld flanges, also known as high-neck flanges, have high rigidity and are suitable for applications with high pressure and temperature.
New users who post should be encouraged. It is best to post questions based on real situations in order to initiate discussions, learn together, improve together, and engage in happy exchanges and sharing
This post was last edited by Chow Tai Fook on 2015-7-7 at 16:34. I’m not sure where the content came from; when I saw “Flat-sealed face flanges (FF, RF), suitable for applications with low pressure and non-toxic media,” I thought there were too many issues. There’s also “Ring-connected face flanges (RJ),” but no further details……
You can check out the Boyirensheng forum in the Piping and Valves section; the lectures on flange series there are very comprehensive: http://bbs.hcbbs.com/thread-1348583-1-1.html
Mm-hmm, thank you. It’s mainly about everyone learning together*
It’s encouraging to speak up actively, but it’s recommended to first search to see if there are similar posts in the forum.
Does the original poster have any pictures? I really can’t figure out what they look like; it would be best to have pictures from the actual location