ANSI Flange Dimensions

Flange Standards
The most common flange standard in the oil and gas industry is arguably American National Standards Institute (ANSI) B16.5.
Other standards are used, e.g.
- British Imperial flanges BS 10,
- Metric flanges SABS 1123, BS 4504, DIN 2501,
- Japanese and Korean flanges JIS-B-2212, JIS-B-2214 & KS-B-1503

ANSI B16.5. Flange Dimensions
The following tables provide flange dimensions, diameters and drillings for the most common sizes and ratings.

ANSI 150 flange sizes

ANSI 300 flange sizes

ANSI 600 flange sizes

ANSI900 flange sizes

ANSI1500 flange sizes



Further Reading - external links

For those who want to delve further into the world of piping, then the following may be of interest: