What is the difference with American standard steel pipe?
1. For flanges, there are two series, European and American, and the same series can be universally matched:
1. National standards (GB/T9112~9124-2000), using both European standard flanges and American flanges.
2. Chemical industry standards (HG20592~20635-1997, HG20592~20635-2009), using both European standard flanges and American standard flanges.
3. Machinery industry standards (JB/T74~86.2-1994), using European standard flanges, no neck flat welding flanges.
4. Petrochemical industry standards (SH3406-1996), using American standard flanges, of which N600mm and above are large diameter butt welding flanges.
2. There are two series of wall thickness of pipes and pipe fittings:
1. Ia series pipes are matched with European standard A series flanges.
2. Ib series pipes are matched with American standard flanges (Ia series and Ib series can be considered the same).
3. II series corresponds to European standard b series flanges. The European standard originated from the German standard. The German standard used to have two types of pipes, AB, but now the European standard EN1092 only has one British pipe A pipe, so the European standard no longer has a B series.
4. European standard A series flanges can only be matched with Ia series pipes. Ia series and Ib series can be considered the same).
5. American standard flanges can only be matched with Ib series pipes. (Ia series and Ib series can be considered the same) The DN65 and DN125 of the American standard are different from the A pipe size, so pay attention when processing the thread.
6. European standard b series flanges can only be matched with II series pipes.
7. Pipes are divided into Ia Ib series, that is, large pipes, that is, A series, British pipes; and II series, that is, small pipes, that is, B series, metric pipes.
