Metric Dimensions of Weld Neck Flange Rating 150 as per ASME B16.5

NPS	O Flange OD	Ttf Thickness	X Hub Dia	A Hub Dia	Y Length	B Bore Dia
1/2	90	9.6	30	21.3	46	15.8
3/4	100	11.2	38	26.7	51	20.9
1	110	12.7	49	33.4	54	26.6
1-1/4	115	14.3	59	42.2	56	35.1
1-1/2	125	15.9	65	48.3	60	40.9
2	150	17.5	78	60.3	62	52.5
2-1/2	180	20.7	90	73	68	62.7
3	190	22.3	108	88.9	68	77.9
3-1/2	215	22.3	122	101.6	70	90.1
4	230	22.3	135	114.3	75	102.3
5	255	22.3	164	141.3	87	128.2
6	280	23.9	192	168.3	87	154.1
8	345	27	246	219.1	100	202.7
10	405	28.6	305	273	100	254.6
12	485	30.2	365	323.8	113	304.8
14	535	33.4	400	355.6	125	BY P
16	595	35	457	406.4	125	BY P
18	635	38.1	505	457	138	BY P
20	700	41.3	559	508	143	BY P
24	815	46.1	663	610	151	BY P

Templates for drilling of bolt holes

NPS	BCD	BHD	BOLTS	BD	SBL RFY	SBL RJ	MBL RF
1/2	60.3	5/8	4	1/2	55	NA	50
3/4	69.9	5/8	4	1/2	65	NA	50
1	79.4	5/8	4	1/2	65	75	55
1-1/4	88.9	5/8	4	1/2	70	85	55
1-1/2	98.4	5/8	4	1/2	70	85	65
2	120.7	3/4	4	5/8	85	95	70
2-1/2	139.7	3/4	4	5/8	90	100	75
3	152.4	3/4	4	5/8	90	100	75
3-1/2	177.8	3/4	8	5/8	90	100	75
4	190.5	3/4	8	5/8	90	100	75
5	215.9	7/8	8	3/4	95	110	85
6	241.3	7/8	8	3/4	100	115	85
8	298.5	7/8	8	3/4	110	120	90
10	362.0	1	12	7/8	115	125	100
12	431.8	1	12	7/8	120	135	100
14	476.3	1-1/8	12	1	135	145	115
16	539.8	1-1/8	16	1	135	145	115
18	577.9	1-1/4	16	1-1/8	145	160	125
20	635.0	1-1/4	20	1-1/8	160	170	140
24	749.3	1-3/8	20	1-1/4	170	185	150

Dimensions are in millimeters, except for diameters of bolts and bolt holes, which are in inch units.