ANSI / ASME B16.5 Class 300 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	3	3.50	4	0.75
1 1/4	5.25	0.75	2.50	1.06	2.50	4	3.88	4	0.75
1 1/2	6.13	0.81	2.88	1.19	2.75	6	4.50	4	0.88
2	6.50	0.88	3.63	1.31	3.31	7	5.00	8	0.75
2 1/2	7.50	1.00	4.13	1.50	3.94	10	5.88	8	0.88
3	8.25	1.13	5.00	1.69	4.63	13	6.63	8	0.88
3 1/2	9.00	1.19	5.50	1.75	5.25	17	7.25	8	0.88
4	10.00	1.25	6.19	1.88	5.75	22	7.88	8	0.88
5	11.00	1.38	7.31	2.00	7.00	28	9.25	8	0.88
6	12.50	1.44	8.50	2.06	8.13	39	10.63	12	0.88
8	15.00	1.63	10.63	2.44	10.25	58	13.00	12	1.00
10	17.50	1.88	12.75	2.62	12.63	81	15.25	16	1.13
12	20.50	2.00	15.00	2.88	14.75	115	17.75	16	1.25
14	23.00	2.13	16.25	3.00	16.75	165	20.25	20	1.25
16	25.50	2.25	18.50	3.25	19.00	190	22.50	20	1.38
18	28.00	2.38	21.00	3.50	21.00	250	24.75	24	1.38
20	30.50	2.50	23.00	3.75	23.13	315	27.00	24	1.38
22	33.00	2.63	25.25	4.00	25.25	370	29.25	24	1.63
24	36.00	2.75	27.25	4.19	27.63	475	32.00	24	1.63

*Use 25.4 as a factor to convert into mm.