The difference between DIN and ANSI, explained in one article
- Flange standard classification
- European flange system
- American flange system
- Instrument pipe flange standard system
Flanges are important parts that connect pipes. There are many types and complicated standards. It is particularly important to understand the different standards of flanges!
Let’s take a good look at the knowledge points here today!
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Flange standard classification
There are many flange standards. Domestically, there are GB (national standard), JB (Ministry of Machinery standard), HG (Ministry of Chemical Industry standard), etc.
Foreign countries include ANSI (American standard), JIS (Japanese standard), DIN (German standard), etc.
However, the standards that are currently used are divided into two categories:
The European system is mainly based on DIN standards (including DIN, GB, JB, HG20592);
The American system is mainly based on ANSI standards (including ANSI, GB, HG20615).
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European flange system
Nominal pressure
0.1, 0.25, 0.6, 1.0, 1.6, 2.5, 4.0, 6.4, 10.0, 16.0, 25.0, 32.0, 40.0, MPA;
Rated diameter
15~600 mm;
Flange structure type
Flat welding plate type, flat welding ring loose sleeve type, curling loose sleeve type, butt welding curling loose sleeve type, butt welding ring loose sleeve type, butt welding type, neck thread connection type, integral type and flange cover;
Flange sealing surface
Flat surface, concave surface, concave-convex surface, tongue-and-groove surface, rubber ring connection surface, lens surface and diaphragm welding surface;
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American flange system
Nominal pressure
150 afraid of death (2.0MPA), 300 afraid of death (5.0MPA), 400 afraid of death (6.8MPA), 600 afraid of death (10.0MPA), 900 afraid of death (15.0MPA), 1500 afraid of death (25.0MPA), 2500 afraid of death (42.0MPA);
Rated diameter
6~4000mm;
Flange structure type
Strip welding, socket welding, threaded connection, loose sleeve, butt welding and flange cover;
Flange sealing surface
Concave surface, concave-convex surface, tongue-and-groove surface, metal ring connection surface.
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Instrument pipe flange standard system
DIN standard
Common pressure levels: PN6, PN10, PN16, PN25, PN40, PN64, PN100, PN160, PN250
Flange sealing surface:
raised face DIN2526C raised face flange
grooued acc. DIN2512N grooved face
ANSI standard
Common pressure levels: CL150, CL300, CL600, CL900, CL1500
Flange sealing surface: ANSI B 16.5 RF flanges
JIS standard
Common pressure levels: 10K, 20K;