1. Technical Drawings for ASME B16.5 Class 900 Flanges

2. Flange and Bolting Dimensions for Class 900

All dimensions are provided in both mm and inch units. The two unit system shall be used respectively and exclusively. The bolting of Class 900 flanges shall be furnished by stud bolt with nuts. The Class 900 flange has a 7 mm(0.25 inch) raised face which is additional to the minimum flange thickness. For sizes of 1/2″~2-1/2″, the dimensions of ASME B16.5 Class 900 flange are the same as that of Class 1500. Tables below are applicable for 900# flanges with RF end facing.

NPS	O mm inch	T mm inch	X mm inch	Ah mm inch	ro mm inch	Q mm inch
1/2	120 4.75	22.3 0.88	38 1.50	21.3 0.84	3 0.12	23.6 0.93
3/4	130 5.12	25.4 1.00	44 1.75	26.7 1.05	3 0.12	29.0 1.14
1	150 5.88	28.6 1.12	52 2.06	33.4 1.32	3 0.12	35.8 1.41
1-1/4	160 6.25	28.6 1.12	64 2.50	42.2 1.66	5 0.19	44.4 1.75
1-1/2	180 7.00	31.8 1.25	70 2.75	48.3 1.90	6 0.25	50.6 1.99
2	215 8.50	38.1 1.50	105 4.12	60.3 2.38	8 0.31	63.5 2.50
2-1/2	245 9.62	41.3 1.62	124 4.88	73.0 2.88	8 0.31	76.2 3.00
3	240 9.50	38.1 1.50	127 5.00	88.9 3.50	10 0.38	92.2 3.63
4	290 11.50	44.5 1.75	159 6.25	114.3 4.50	11 0.44	117.6 4.63
5	350 13.75	50.8 2.00	190 7.50	141.3 5.56	11 0.44	144.4 5.69
6	380 15.00	55.6 2.19	235 9.25	168.3 6.63	13 0.50	171.4 6.75
8	470 18.50	63.5 2.50	298 11.75	219.1 8.63	13 0.50	222.2 8.75
10	545 21.50	69.9 2.75	368 14.50	273.0 10.75	13 0.50	276.2 10.88
12	610 24.00	79.4 3.12	419 16.50	323.8 12.75	13 0.50	328.6 12.94
14	640 25.25	85.8 3.38	451 17.75	355.6 14.00	13 0.50	360.4 14.19
16	705 27.75	88.9 3.50	508 20.00	406.4 16.00	13 0.50	411.2 16.19
18	785 31.00	101.6 4.00	565 22.25	457.0 18.00	13 0.50	462.0 18.19
20	855 33.75	108.0 4.25	622 24.50	508.0 20.00	13 0.50	512.8 20.19
24	1040 41.00	139.7 5.50	749 29.50	610.0 24.00	13 0.50	614.4 24.19

*O:outside diameter of flange; T:minimum flange thickness(T=T_o=T₁); X:diameter at hub.
*A_h:hub diameter at the beginning of chamfer for W/N; r_o: corner bore radius of lapped flange; Q:minimum counterbore of threaded flange.

NPS	Y1 mm inch	Y2 mm inch	Y3 mm inch	Ta mm inch	B1 mm inch	B2 mm inch	B3 mm inch
1/2	60 2.38	32 1.25	32 1.25	23 0.88	-	22.2 0.88	22.9 0.90
3/4	70 2.75	35 1.38	35 1.38	26 1.00	-	27.7 1.09	28.2 1.11
1	73 2.88	41 1.62	41 1.62	29 1.12	-	34.5 1.36	34.9 1.38
1-1/4	73 2.88	41 1.62	41 1.62	31 1.19	-	43.2 1.70	43.7 1.72
1-1/2	83 3.25	44 1.75	44 1.75	32 1.25	-	49.5 1.95	50.0 1.97
2	102 4.00	57 2.25	57 2.25	39 1.50	-	61.9 2.44	62.5 2.46
2-1/2	105 4.12	64 2.50	64 2.50	48 1.88	-	74.6 2.94	75.4 2.97
3	102 4.00	54 2.12	54 2.12	42 1.62	-	90.7 3.57	91.4 3.60
4	114 4.50	70 2.75	70 2.75	48 1.88	-	116.1 4.57	116.8 4.60
5	127 5.00	79 3.12	79 3.12	54 2.12	-	143.8 5.66	144.4 5.69
6	140 5.50	86 3.38	86 3.38	58 2.25	-	170.7 6.72	171.4 6.75
8	162 6.38	102 4.00	114 4.50	64 2.50	-	221.5 8.72	222.2 8.75
10	184 7.25	108 4.25	127 5.00	72 2.81	-	276.2 10.88	277.4 10.92
12	200 7.88	117 4.62	143 5.62	77 3.00	-	327.0 12.88	328.2 12.92
14	213 8.38	130 5.12	156 6.12	83 3.25	-	359.2 14.14	360.2 14.18
16	216 8.50	133 5.25	165 6.50	86 3.38	-	410.5 16.16	411.2 16.19
18	229 9.00	152 6.00	190 7.50	89 3.50	-	461.8 18.18	462.3 18.20
20	248 9.75	159 6.25	210 8.25	93 3.62	-	513.1 20.20	514.4 20.25
24	292 11.50	203 8.00	267 10.50	102 4.00	-	616.0 24.25	616.0 24.25

*Y₁:length through hub of welding neck flange; Y₂:length through hub of threaded, S/O; Y₃:length through hub of lapped flange.
*T_a:minimum thread length of threaded flange; B₁:bore diameter of welding neck flange which shall be specified by purchaser.
*B₂:bore diameter of slip on flange; B₃:bore diameter of lap joint(lapped) flange.

NPS	W mm inch	R mm inch	d inch	n	do inch	LSRF mm inch	LSRJ mm inch	LTG mm inch
1/2	82.6 3.25	34.9 1.38	7/8	4	3/4	110 4.25	110 4.25	100 4.00
3/4	88.9 3.50	42.9 1.69	7/8	4	3/4	115 4.50	115 4.50	110 4.25
1	101.6 4.00	50.8 2.00	1	4	7/8	125 5.00	125 5.00	120 4.75
1-1/4	111.1 4.38	63.5 2.50	1	4	7/8	125 5.00	125 5.00	120 4.75
1-1/2	123.8 4.88	73.0 2.88	1 1/8	4	1	140 5.50	140 5.50	135 5.25
2	165.1 6.50	92.1 3.62	1	8	7/8	145 5.75	145 5.75	140 5.50
2-1/2	190.5 7.50	104.8 4.12	1 1/8	8	1	160 6.25	160 6.25	150 6.00
3	190.5 7.50	127.0 5.00	1	8	7/8	145 5.75	145 5.75	140 5.50
4	235.0 9.25	157.2 6.19	1 1/4	8	1 1/8	170 6.75	170 6.75	165 6.50
5	279.4 11.00	185.7 7.31	1 3/8	8	1 1/4	190 7.50	190 7.50	185 7.25
6	317.5 12.50	215.9 8.50	1 1/4	12	1 1/8	190 7.50	195 7.75	185 7.25
8	393.7 15.50	269.9 10.62	1 1/2	12	1 3/8	220 8.75	220 8.75	215 8.50
10	469.9 18.50	323.8 12.75	1 1/2	16	1 3/8	235 9.25	235 9.25	230 9.00
12	533.4 21.00	381.0 15.00	1 1/2	16	1 3/8	255 10.00	255 10.00	250 9.75
14	558.8 22.00	412.8 16.25	1 5/8	20	1 1/2	275 10.75	280 11.00	265 10.50
16	616.0 24.25	469.9 18.50	1 3/4	20	1 5/8	285 11.25	290 11.50	280 11.00
18	685.8 27.00	533.4 21.00	2	20	1 7/8	325 12.75	335 13.25	320 12.50
20	749.3 29.50	584.2 23.00	2 1/8	20	2	350 13.75	360 14.25	345 13.50
24	901.7 35.50	692.2 27.25	2 5/8	20	2 1/2	440 17.25	455 18.00	430 17.00

*W:diameter of bolt circle; d:diameter of bolt holes; n:number of bolts; d_o:diameter of bolts; R:outside diameter of RF.
*L_SRF:length of stud bolt for raised face; L_SRJ:length of stud bolt for ring joint; L_TG:length of stud bolt for male/ female tongue and groove.