1. According to the chemical (HG) industry standard: integral flange (IF), threaded flange (Th), plate flat welding flange (PL), neck welding flange (WN), neck flat welding flange (SO), socket welding flange (SW), welding ring loose flange (PJ/SE), flat welding ring loose flange (PJ/RJ), lined flange cover (BL(S)), flange cover (BL).
2. According to the petrochemical (SH) industry standard: threaded flange (PT), welding flange (WN), flat welding flange (SO), socket welding flange (SW), loose flange (LJ), flange cover (not specified).
3. According to the machinery (JB) industry standard: integral flange, welding flange, plate flat welding flange, welding ring plate loose flange, flat welding ring plate loose flange, flanged ring plate loose flange, flange cover.
4. According to national (GB) standards: integral flanges, threaded flanges, welding flanges, necked slip-on flanges, necked socket welding flanges, welding ring necked loose flanges, plate slip-on flanges, welding ring plate loose flanges, slip-on ring plate loose flanges, flanged ring plate loose flanges, and flange covers.
