| Standard ID | HG 20620-1997 (HG20620-1997) |
| Description (Translated English) | (Steel pipe flanges (American System)) |
| Sector / Industry | Chemical Industry Industry Standard |
| Classification of Chinese Standard | J15 |
| Classification of International Standard | 23.040.60 |
| Word Count Estimation | 31,377 |
| Date of Issue | 1997/11/27 |
| Date of Implementation | 1998/2/1 |
| Older Standard (superseded by this standard) | HGJ 44��76-1991 |
| Adopted Standard | ISO 7005-1-1992, NEQ; ANSI B16.5-1988, NEQ |
| Regulation (derived from) | Industry-Science [2009] No. 27 |