ANSI / ASME B16.5 Class 400 Threaded Flange Dimensions

Nominal Pipe Size	Outside Diameter (O)	Thickness (T)	Raised Face Diameter (R)	Length Thru Hub (Y)	Hub Diameter (X)	Approximate Weight (lbs)	Bolt Circle (C)	Number of Holes	Diameter of Holes
1/2	3.75	0.56	1.38	0.88	1.50	2	2.63	4	0.63
3/4	4.63	0.63	1.69	1.00	1.88	3	3.25	4	0.75
1	4.88	0.69	2.00	1.06	2.13	4	3.50	4	0.75
1 1/4	5.25	0.81	2.50	1.13	2.50	5	3.88	4	0.75
1 1/2	6.13	0.88	2.88	1.25	2.75	7	4.50	4	0.88
2	6.50	1.00	3.63	1.44	3.31	9	5.00	8	0.75
2 1/2	7.50	1.13	4.13	1.63	3.94	13	5.88	8	0.88
3	8.25	1.25	5.00	1.81	4.63	16	6.63	8	0.88
3 1/2	9.00	1.38	5.50	1.94	5.25	21	7.25	8	1.00
4	10.00	1.38	6.19	2.00	5.75	26	7.88	8	1.00
5	11.00	1.50	7.31	2.13	7.00	31	9.25	8	1.00
6	12.50	1.63	8.50	2.25	8.13	44	10.63	12	1.00
8	15.00	1.88	10.63	2.69	10.25	67	13.00	12	1.13
10	17.50	2.13	12.75	2.88	12.63	91	15.25	16	1.25
12	20.50	2.25	15.00	3.13	14.75	130	17.75	16	1.38
14	23.00	2.38	16.25	3.31	16.75	180	20.25	20	1.38
16	25.50	2.50	18.50	3.69	19.00	235	22.50	20	1.50
18	28.00	2.63	21.00	3.88	21.00	285	24.75	24	1.50
20	30.50	2.75	23.00	4.00	23.13	345	27.00	24	1.63
22	33.00	2.88	25.25	4.25	25.25	405	29.25	24	1.75
24	36.00	3.00	27.25	4.50	27.63	510	32.00	24	1.88

*Use 25.4 as a factor to convert into mm.