ASME B16.47 Blind Flange Dimension

In modern industries such as oil & gas, power generation, petrochemical, seawater desalination, and offshore platforms, large-diameter pipelines operate under high pressure, high temperature, and corrosive conditions. Flanges must provide excellent sealing, mechanical strength, and long-term stability, with ASME B16.47 blind flange playing a key role in isolating pipeline ends, equipment outlets, or system branches to prevent leaks and allow maintenance.

ASME B16.47 Standard

The ASME B16.47 standard is an essential specification for large-diameter steel flanges. It fills the size range that ASME B16.5 does not cover, expanding the diameter range from NPS 1/2–24 up to NPS 26–60. ASME B16.47 standard includes detailed requirements for design, dimensions, tolerances, bolt-hole configurations, pressure ratings, and materials. One of the key characteristics of ASME B16.47 is the division into Series A and Series B, each serving different industrial needs:

•Series A is generally thicker, heavier, and designed for higher mechanical loads. It follows the MSS SP-44 standard.

•Series B is more compact, lighter, and often used in systems where space or weight is a concern. It originates from the API 605 standard.

The pressure classes included in ASME B16.47 are Class 75, 150, 300, 400, 600, and 900.

ASME B16.47 Blind Flange

An ASME B16.47 Blind Flange is a solid plate without a bore, used to seal or isolate the end of a pipeline or equipment nozzle. Its role is critical because it must withstand the full internal pressure of the system. When working with large diameters such as NPS 26–60, this pressure creates substantial force, so the flange must be manufactured with strict control over thickness, material strength, and flange facing accuracy.

The ASME B16.47 Blind Flange is available as Series A or Series B, providing different structural characteristics:

•Series A Blind Flanges offer greater thickness and higher bending resistance, making them ideal for demanding mechanical loads.

•Series B Blind Flanges are lighter and more economical but still meet industrial performance requirements.

Blind flanges also come with different sealing faces: Raised Face (RF) for standard applications and Ring-Type Joint (RTJ) for high-pressure or high-temperature environments. Due to the lack of a bore, the ASME B16.47 Blind Flange experiences higher stress distribution at the center, which is why proper forging, heat treatment, and machining accuracy are essential.

ASME B16.47 vs. ASME B16.5 Blind Flange

Feature	ASME B16.47 Blind Flange	ASME B16.5 Blind Flange
Applicable Pipe Size	NPS 26 – 60 (large-diameter)	NPS 1/2 – 24 (medium/small-diameter)
Series	Series A & Series B	–
Pressure Classes	Class 75, 150, 300, 400, 600, 900	Class 150, 300, 400, 600, 900, 1500, 2500 (depending on size and material)
Sealing Face Types	RF, FF, RTJ	RF, FF, RTJ
Typical Applications	Large pipelines in oil & gas, petrochemical, seawater, power generation	Medium/small pipelines in process and utility systems
Design Focus	Withstand higher stress due to large diameter; bolt pattern, thickness, and tolerances are stricter; Series A vs Series B differences in dimensions	Standard stress for medium and small diameters; conventional bolt pattern and tolerances

ASME B16.47 Flange Dimensions

ASME B16.47 flange standard uses nominal size (NPS) and nominal pressure (Class) as core indicators.

B16.47 Series A Class 150 Flange Dimension

Nominal Pipe Size	A	C		D	E	F	G	H	I	J	R
Nominal Pipe Size	mm	mm	mm	mm	mm	mm	mm	Holes	mm	mm	mm
22	749.3	45.97	45.97	149.35	558.8	609.6	641.35	20	35.05	692.15	9.65
26	869.95	68.33	68.33	120.65	660.4	676. 15	749.3	24	35.05	806.45	9.65
28	927.1	71.37	71.37	125.48	711.2	726.95	800.1	28	35.05	863.6	11.18
30	984.25	74.68	74.68	136.65	762	781.05	857.25	28	35.05	914.4	11.18
32	1060.5	81.03	81.03	144.53	812.8	831.85	914.4	28	41.15	977.9	11.18
34	1111.3	82.55	82.55	149.35	863.6	882.65	965.2	32	41.15	1028.7	12.70
36	1168.4	90.42	90.42	157.23	914.4	933.45	1022.4	32	41.15	1085.9	12.70
38	1238.3	87.38	87.38	157.23	965.2	990.60	1073.2	32	41.15	1149.4	12.70
40	1289.1	90.42	90.42	163.58	1016	1041.4	1124.0	36	41.15	1200.2	12.70
42	1346.2	96.77	96.77	171.45	1066.8	1092.2	1193.8	36	41.15	1257.3	12.70
44	1403.4	101.6	101.60	177.80	1117.6	1143	1244.6	40	41.15	1314.5	12.70
46	1454.2	103. 12	103.12	185.67	1168.4	1196.9	1295.4	40	41.15	1365.3	12.70
48	1511.3	107.95	107.95	192.02	1219.2	1247.7	1358.9	44	41.15	1422.4	12.70

B16.47 Series A Class 300 Flange Dimension

Nominal Pipe Size	A	C		D	E	F	G	H	I	J	R
Nominal Pipe Size	mm	mm	mm	mm	mm	mm	mm	Holes	mm	mm	mm
22	838.20	66.55	66.55	165.1	558.80	641.35	641.35	24	41.15	742.95	9.65
26	971.55	79.25	84.07	184.15	660.40	720.85	749.30	28	44.45	876.30	9.65
28	1035.1	85.85	90.42	196.85	711.20	774.70	800.10	28	44.45	939.80	11. 18
30	1092.2	91.95	95.25	209.55	762.00	827.02	857.25	28	47.75	996.95	11. 18
32	1149.4	98.55	100.08	222.25	812.80	881.13	914.40	28	50.80	1054. 1	11. 18
34	120.50	101.60	104.65	231.65	863.60	936.75	965.20	28	50.80	1104.9	12.70
36	1270.0	104.65	111.25	241.30	914.40	990.60	1022.40	32.00	53.85	1168.40	12.70
38	1168.4	107.95	107.95	180.85	965.20	993.65	1028.70	32.00	41.15	1092.20	12.70
40	1238.3	114.30	114.30	193.55	1016.00	1047.8	1085.90	32.00	44.45	1155.70	12.70
42	1289.1	119.13	119.13	200.15	1066.80	1098.6	1136.70	32.00	44.45	1206.60	12.70
44	1352.6	123.95	123.95	206.25	1117.60	1149.4	1193.80	32.00	47.75	1263.70	12.70
46	1416.1	128.52	128.52	215.90	1168.40	1203.5	1244.00	28.00	50.80	1320.80	12.70
48	1466.9	133.35	133.35	223.77	1219.20	1254.3	1301.80	32.00	50.80	1371.60	12.70

B16.47 Series B Class 150 Flange Dimension

Nominal Pipe Size	A	C		D	E	F	G	H	I	J	R
Nominal Pipe Size	mm	mm	mm	mm	mm	mm	mm	Holes	mm	mm	mm
26	785.88	41.15	44.45	88.90	661.92	684.28	711.20	36	22.35	744.47	9.65
28	836.68	44.45	47.75	95.25	712.72	735.08	762.00	40	22.35	795.27	9.65
30	887.48	44.45	50.80	100.08	763.52	787.40	812.80	44	22.35	846.07	9.65
32	941.32	45.97	53.85	107.95	814.32	839.72	863.60	48	22.35	900.18	9.65
34	1004.8	49.28	57.15	110.24	865.12	892.05	920.75	40	25.40	957.33	9.65
36	1057.1	52.32	58.67	117.35	915.92	944.63	971.55	44	25.40	1009.7	9.65
38	1124.0	53.85	63.50	123.95	968.25	996.95	1022.4	40	28.45	1069.8	9.65
40	1174.8	55.63	66.55	128.52	1019.0	1049.3	1079.5	44	28.45	1120.6	9.65
42	1225.6	58.67	68.33	133.35	1069.8	1101.9	1130.3	48	28.45	1171.4	11.18
44	1276.4	60.45	71.37	136.65	1120.6	1152.7	1181.1	52	28.45	1222.2	11.18
46	1341.4	61.98	74.68	144.53	1171.4	1205.0	1234.9	40	31.75	1284.2	11.18
48	1392.2	65.02	77.72	149.35	1222.2	1257.3	1289.1	44	31.75	1335.0	11.18

B16.47 Series B Class 300 Flange Dimension

Nominal Pipe Size	A	C		D	E	F	G	H	I	J	R
Nominal Pipe Size	mm	mm	mm	mm	mm	mm	mm	Holes	mm	mm	mm
26	866.65	88.90	88.90	144.53	665.23	701.55	736.60	32	35.05	803.15	14.22
28	920.75	88.90	88.90	149.35	716.03	755.65	787.40	36	35.05	857.25	14.22
30	990.60	93.73	93.73	157.99	768.35	812.80	844.55	36	38.10	920.75	14.22
32	1054.1	103.12	103.12	168. 15	819.15	863.60	901.70	32	41.15	977.90	15.75
34	1107.9	103.12	103.12	172.97	869.95	917.45	952.50	36	41.15	1031.7	15.75
36	1171.4	103.12	103.12	180.85	920.75	965.20	1009.7	32	44.45	1089.2	15.75
38	1222.2	111.25	111.25	192.02	971.55	1016.0	1060.5	36	44.45	1140.0	15.75
40	1273.0	115.82	115.82	198.37	1022.4	1066.8	1114.6	40	44.45	1190.8	15.75
42	1333.5	119.13	119.13	204.72	1074.7	1117.6	1168.4	36	47.75	1244.6	15.75
44	1384.3	127.00	127.00	214.38	1125.5	1173.2	1219.2	40	47.75	1295.4	15.75
46	1460.5	128.52	130.05	222.25	1176.3	1228.9	1270.0	36	50.80	1365.3	15.75
48	1511.3	128.52	134.87	223.77	1227.1	1277.9	1327.2	40	50.80	1416. 1	15.75

Flange Common Material (A105 & A182)

ASTM A105 & A105N Material

CHEMICAL	LIMITS	C	Mn	P	S	Si	Cu	Ni	Cr	Mo	V
ASTM A105	MIN		0.60			0.10
ASTM A105	MAX	0.35	1.05	0.035	0.040	0.35	0.40	0.40	0.30	0.12	0.08
ASTM A105N	MIN		0.600
ASTM A105N	MAX	0.350	1.050	0.040	0.050		0.400		0.300	0.120	0.080

ASTM A182 Material

CHEMICAL	LIMITS	C	Mn	P	S	Si	Ni	Cr	Mo	N
ASTM A182 F304	MIN						8.0	18.0
ASTM A182 F304	MAX	0.08	2.00	0.045	0.030	1.00	11.0	20.0		0.10
ASTM A182 F304L	MIN						8.00	18.00
ASTM A182 F304L	MAX	0.03	2.00	0.045	0.030	1.00	13.00	20.00		0.10
ASTM A182 F316	MIN						10.0	16.0	2.00
ASTM A182 F316	MAX	0.08	2.00	0.045	0.030	1.00	14.0	18.0	3.00	0.10
ASTM A182 F316L	MIN						10.00	16.0	2.00
ASTM A182 F316L	MAX	0.03	2.00	0.045	0.030	1.00	15.00	18.0	3.00	0.10
ASTM A182 F904L	MIN						23.00	19.00	4.00
ASTM A182 F904L	MAX	0.02	2.00	0.040	0.030	1.00	28.00	23.00	5.00	0.10