ANSI / ASME B16.47 Series A Class 400 Weld Neck Flange Dimensions

Nominal Pipe Size	Outside Diameter (O)	Min Thickness (T)	Raised Face Diameter (R)	Length Thru Hub (Y)	Hub Diameter (X)	Minimum Fillet Radius (r)	Top of Hub (A)	Bore (B)	Approximate Weight (lbs)	Bolt Circle (C)	Number of Holes	Diameter of Holes
26	38.25	3.50	29.50	7.62	28.62	0.44	26.00	Specified by purchaser	650	34.50	28	1.88
28	40.75	3.75	31.50	8.12	30.81	0.50	28.00	Specified by purchaser	785	37.00	28	2.00
30	43.00	4.00	33.75	8.62	32.94	0.50	30.00	Specified by purchaser	905	39.25	28	2.12
32	45.25	4.25	36.00	9.12	35.00	0.50	32.00	Specified by purchaser	1065	41.50	28	2.12
34	47.50	4.38	38.00	9.50	37.19	0.56	34.00	Specified by purchaser	1200	43.50	28	2.12
36	50.00	4.50	40.25	9.88	39.38	0.56	36.00	Specified by purchaser	1340	46.00	32	2.12
38	47.50	4.88	40.75	8.12	39.50	0.56	38.00	Specified by purchaser	935	44.00	32	1.88
40	50.00	5.12	43.00	8.50	41.50	0.56	40.00	Specified by purchaser	1090	46.25	32	2.00
42	52.00	5.25	45.00	8.81	43.62	0.56	42.00	Specified by purchaser	1190	48.25	32	2.00
44	54.50	5.50	47.25	9.18	45.62	0.56	44.00	Specified by purchaser	1375	50.50	32	2.12
46	56.75	5.75	49.50	9.62	47.75	0.56	46.00	Specified by purchaser	1525	52.75	36	2.12
48	59.50	6.00	51.50	10.12	49.88	0.56	48.00	Specified by purchaser	1790	55.25	28	2.38
50	61.75	6.19	53.62	10.56	52.00	0.56	50.00	Specified by purchaser	1950	57.50	32	2.38
52	63.75	6.38	55.62	10.88	54.00	0.56	52.00	Specified by purchaser	2125	59.50	32	2.38
54	67.00	6.69	57.88	11.38	56.12	0.56	54.00	Specified by purchaser	2565	62.25	28	2.62
56	69.00	6.88	60.12	11.75	58.25	0.56	56.00	Specified by purchaser	2710	64.25	32	2.62
58	71.00	7.00	62.12	12.06	60.25	0.56	58.00	Specified by purchaser	3230	66.25	32	2.62
60	74.25	7.31	64.38	12.56	62.38	0.56	60.00	Specified by purchaser	3820	69.00	32	2.88

*Use 25.4 as a factor to convert into mm.