Butt weld flange is also called WN neck butt weld flange. It refers to a flange with a neck and a round pipe transition and connected to the pipe butt weld. Butt weld flange is not easy to deform, good sealing, widely used, has corresponding rigidity and elasticity requirements and reasonable butt weld thinning transition, weld is far from the joint surface and The joint surface is protected from deformation by welding temperature. The sealing surface of the butt weld flange is generally a protruding surface (RF), concave-convex type (FM concave-convex M), tongue-and-groove type is not commonly used. The butt welding flange is suitable for pipelines with large pressure or temperature fluctuations or pipelines with high temperature, high pressure and low temperature, and is also used in pipelines transporting oil, chemicals, flammable and explosive media. The welding method used when butt welding flange flange and pipe connection is butt welding, welding is similar to pipe and pipe welding, generally small diameter pipe is used priming Argon arc welding, manual welding cover, pipe diameter is large only with double-sided welding.
Flanges, also known as flanges, are the parts that connect pipes to each other. There are holes in the flange, the bolt makes the two flanges closely connected, the flange connection refers to the flange, the gasket and the bolt three interconnected as a set of combined sealing structure of the detachable connection, the flange Pipe refers to the flange used in the piping device, used in the equipment refers to the inlet and outlet flange of the equipment. The flange is sealed with a gasket. The flange is divided into threaded flange and welded flange.
Flanges can be divided into carbon steel: (20#, A3, Q235, Q235A, Q235B, 20G, 16Mn, Q345, Q345R, ASTM A234WPB, ASTM A105, etc.); Stainless steel: (304, 304L, 316, 316L, S30408, S30403, S31608, S31603, SUS304, ASTM A403, TP321, TP317L, 347, 0Cr18Ni9, 00Cr19Ni10, , 1Cr18Ni9Ti, 06Cr17Ni12Mo2 , 022Cr17Ni12Mo2, etc.); Alloy steel: (16MnR, Cr5Mo, 12Cr1MoV, 10CrMo910, 15CrMo, 12Cr2Mo1, A335P22, St45.8/III., A10bB, etc.); Special alloy steel: (TP310S, 904L, Incoloy800, Incoloy825, Incoloy600, Incoloy625, etc.); Duplex stainless steel: (F51, S31803, S2205, F53, 2507, S32750, F55, 2607, S32760, etc.);
Commonly used flange types and codes: 1, PL plate flat weld flange, 2, SO flat weld flange with neck, 3, WN with neck butt weld flange, 4, SW socket weld flange, 5, Th thread flange, 6, BL flange cover, 7, figure eight blind, 8, PJ/SE with neck butt weld ring loose sleeve flange, 9, PJ/flat weld ring loose flange PR, 10, Reducing Flange, 11, Stainless Steel Flange, 12, Pressure Vessel Flange, 13, American Standard Flat Weld Flange, 14, American Standard SO Flat Weld Flange with Neck, 15, American Standard WN with Flange butt welding
The commonly used sealing surface shape codes of flanges: RF protruding, FM concave, M convex, T herringbone, G groove, FF full plane, RJ ring connecting surface
Commonly used implementation standards for high neck butt weld flanges: China's current flange standards are divided into two systems, namely PN series (European system) and Class series (American system). The pressure marking specified in this standard is divided into PN marking and class marking. The PN marking has 12 pressure levels, namely: PN2.5; PN6; PN10; PN16; PN25; PN40; PN63; PN100; PN160; PN250; PN320; PN400. Class markings have 6 pressure levels: Class 150; Class 300; Class 600; Class 900; Class1500; Class 2500. Implementation standards include GB series (national standard), JB series (mechanical department), HG series (chemical department), ASME B16.5 (American standard), BS4504 (British standard), DIN (standard German), JIS (Japanese standard).
National flange standards: GB/T9112-2010, GB/T9119-2010, GB/T9116-2010, GB/T9115-2010
Flange Chemical Industry Department Standards: HG/T20592-2009, HG/T20615-2009, HG5010-52 ~ HG5028-58, HGJ44-91 ~ HGJ 65-91, HG20592-97
American Standard for Flanges: ASME B16.5, ASME B16.47
Flange Machinery Department Standards: JB81-59~JB86-59, JB/T79-94~JB/T86-94, JB/T74-1994
Flange pressure vessel standards: NB/T47020-2012, NB/T47021-2012 (JB/T4701), NB/T47022-2012 (JB/T4702), NB/T{{ 5}} (JB/T4703), NB/T47024-2012 (JB/T4704)
