ANSI / ASME B16.5 Class 400 Blind Flange Dimensions

Nominal Pipe Size	Outside Diameter (O)	Thickness (T)	Raised Face Diameter (R)	Approximate Weight (lbs)	Bolt Circle (C)	Number of Holes	Diameter of Holes
1/2	3.75	0.56	1.38	2	2.63	4	0.63
3/4	4.63	0.63	1.69	3	3.25	4	0.75
1	4.88	0.69	2.00	4	3.50	4	0.75
1 1/4	5.25	0.81	2.50	5	3.88	4	0.75
1 1/2	6.13	0.88	2.88	8	4.50	4	0.88
2	6.50	1.00	3.63	10	5.00	8	0.75
2 1/2	7.50	1.13	4.13	15	5.88	8	0.88
3	8.25	1.25	5.00	20	6.63	8	0.88
3 1/2	9.00	1.38	5.50	29	7.25	8	1.00
4	10.00	1.38	6.19	33	7.88	8	1.00
5	11.00	1.50	7.31	44	9.25	8	1.00
6	12.50	1.63	8.50	61	10.63	12	1.00
8	15.00	1.88	10.63	100	13.00	12	1.13
10	17.50	2.13	12.75	155	15.25	16	1.25
12	20.50	2.25	15.00	225	17.75	16	1.38
14	23.00	2.38	16.25	290	20.25	20	1.38
16	25.50	2.50	18.50	370	22.50	20	1.50
18	28.00	2.63	21.00	455	24.75	24	1.50
20	30.50	2.75	23.00	587	27.00	24	1.63
22	33.00	2.88	25.25	720	29.25	24	1.75
24	36.00	3.00	27.25	890	32.00	24	1.88

*Use 25.4 as a factor to convert into mm.