Flange with neck is a proper term, which is divided into flat welding flange with neck and butt welding flange with neck. The internationally accepted pipe flange standards can be summarized as two different and non-interchangeable pipe flange systems.

There are two main international pipe flange standards, namely the European pipe flange system represented by German DIN (including the former Soviet Union) and the American pipe flange system represented by American ANSI pipe flanges. In addition, there are Japanese JIS pipe flanges, but they are generally only used for public works in petrochemical plants, and have little impact internationally. Now the pipe flanges of various countries are introduced as follows:

1. European system pipe flanges represented by Germany and the former Soviet Union

2. American system pipe flange standard, represented by ANSI B16.5 and ANSI B 16.47

3. British and French pipe flange standards, each of which has two sleeve flange standards.

To sum up, the internationally accepted pipe flange standards can be summarized into two different and non-interchangeable pipe flange systems: one is the European pipe flange system represented by Germany; the other is represented by the United States American pipe flange system.

IOS7005-1 is a standard promulgated by the International Organization for Standardization in 1992. This standard is actually a pipe flange standard that combines two series of pipe flanges from the United States and Germany.

1. According to the chemical industry (HG) industry standard: integral flange (IF), threaded flange (Th), plate flat welding flange (PL), neck flange, socket welding flange (SW), butt welding Ring loose flange (PJ/SE), flat welding ring loose flange (PJ/RJ), lining flange cover (BL (S)), flange cover (BL).

2. According to the petrochemical (SH) industry standard: threaded flange (PT), butt welding flange (WN), flat welding flange (SO), socket welding flange (SW), loose flange (LJ) , Flange cover (not shown).

3. According to the mechanical (JB) industry standard: integral flange, butt welding flange, plate flat welding flange, butt welding ring plate loose flange, flat welding ring plate loose flange, flanging ring plate loose flange Flange, flange cover.

4. According to the national (GB) standard: integral flange, threaded flange, butt welding flange, neck flange, plate flat welding flange, butt welding ring plate loose flange, flat welding ring plate loose method Flange, flanging ring plate loose flange, flange cover.