Classification of flange:
Plate type flat welded steel pipe flange
1. According to the chemical (Hg) industry standard, it can be divided into integral flange (if), threaded flange (th), plate flat welding flange (PL), neck butt welding flange (WN), neck flat welding flange (so), 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].
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 indicated).
3. According to JB industry standard, it is divided into integral flange, butt welding flange, flat welding flange, butt welding ring plate loose flange, flat welding ring plate loose flange, flanging ring plate loose flange and flange cover.
4. According to the national (GB) standard: integral flange, threaded flange, butt welding flange, flat welding flange with neck, socket welding flange with neck, butt welding ring with neck loose flange, plate flat welding flange, butt welding ring plate loose flange, flat welding ring plate loose flange, flanging ring plate loose flange, flange cover.
