INDUSTRY STANDARD FLANGES Class 175 – Slip-on and Blind Flanges

Nominal Size NPS		Outside Diameter of Flange	Diameter Of Hub At Base	Outside Diameter of Flange	Diameter Of Hub At Base	Thickness of Flange			Length thru Hub	Diameter Of Raised Face	Diameter of Bolt Circle		Number of Bolt Holes	Diameter of Bolt Holes
		Outside Diameter of Flange	Diameter Of Hub At Base	Outside Diameter of Flange	Diameter Of Hub At Base	SOF	BLIND		Length thru Hub	Diameter Of Raised Face
		O	X	O	X	C	C	C	Y	R
		I.D. VESSELS		O.D. VESSELS			I.D. VESS.	O.D. VESS.			I.D. VESS.	O.D. VESS.
26	in.	32	28.25	31.5	27.62	1.38	1.81	1.88	2.75	29	30.5	29.88	28	0.88
	mm	812.8	717.5	800.1	701.5	35.1	46	47.8	69.8	736.6	774.7	759		22.4
28	in.	34	30.25	33.5	29.62	1.38	1.94	2	2.75	31	32.5	31.88	28	0.88
	mm	863.6	768.3	850.9	752.3	35.1	49.3	50.8	69.8	787.4	825 5	809.8		22.4
30	in.	36.5	32.75	35.75	31.88	1.38	2.12	2.12	2.75	33.25	35	34.12	36	0.88
	mm	927.1	831.8	908	809.8	35.1	53.8	53.8	69.8	844.5	889	866.6		22.4
32	in.	38.5	34.75	37.75	33.88	1.38	2.25	2.25	2.75	35.25	37	36.12	36	0.88
	mm	977.9	882.6	958.8	860.6	35.1	57.1	57.1	69.8	895.3	939.8	917.4		22.4
34	in.	41	36.75	40.25	35.88	1.75	2.38	2.38	3.38	37.38	39.25	38.38	36	1
	mm	1041.4	933.4	1022.3	911.4	44.4	60.5	60.5	85.9	949.5	996.9	974.9		25.4
36	in.	43	38.75	42.25	37.88	1.75	2.5	2.5	3.38	39.38	41.25	40.38	36	1
	mm	1092.2	904.3	1073.1	962.2	44.4	63.5	63.5	85.9	1000.3	1047.8	1025.7		25.4
38	in.	45.25	41	44.25	39.88	2	2.62	2.62	3.75	41.38	43.5	42.38	36	1
	mm	1149.3	1041.4	1124	1013	50.8	66.5	66.5	95.3	1051.1	1104.9	1076.5		25.4
40	in.	47.25	43	46.25	41.88	2	2.75	2.75	4	43.38	45 50	44.38	40	1
	mm	1200.1	1092.2	1174.8	1063 8	50.8	69.8	69.8	101.6	1101.9	1155.7	1127.3		25.4
42	in.	49.75	45	49	44.12	2.38	2.88	2.88	4.38	45.75	47.75	46.88	40	1.12
	mm	1263.6	1143	1244.6	1120.6	60.5	73.2	73.2	111.3	1162.1	1212.8	1190.8		28.4
44	in.	51.75	47	51	46.12	2.38	3	3	4.38	47.75	49.75	48.88	40	1.12
	mm	1314.4	1193.8	1295.4	1171.4	60.5	76.2	76.2	111.3	1212.8	1263 6	1241.6		28.4
46	in.	54	49.25	53	48.12	2.38	3.12	3.12	4.62	49.75	52	50.88	40	1.12
	mm	1371.6	1250.9	1346.2	1222.2	60.5	79.2	79.2	117.3	1263.6	1320.8	1292.4		28.4
48	in.	56	55	55	50.12	2.62	3.25	3.38	4.88	51.75	54	52.88	44	1.12
	mm	1422.4	1301.8	1397	1273	66.5	82.5	85.9	124	1314.4	1371.6	1343.2		28.4
50	in.	58.25	53.5	57	52.12	2.62	3.38	3.38	4.88	53.75	56.5	54.88	44	1.12
	mm	1479.6	1358.9	1447.8	1323.8	66.5	85.9	85.9	124	1365.3	1435.1	1394		28.4
52	in.	60.75	55.5	59.5	54.25	3	3.5	3.62	5.38	56	58.5	57.25	44	1.25
	mm	1543.1	1409.7	1511.3	1377.9	76.2	88.9	91.9	136.7	1422.4	1485 9	1454.1		31.8
54	in.	63	57.75	61.5	56.25	3	3.62	3.62	5.38	58	60.75	59.25	44	1.25
	mm	1600.2	1466.8	1562.1	1428.8	76.2	91.9	91.9	136.7	1473.2	1543.1	1504.9		31.8
60	in.	69	63.75	67.5	62.25	3.12	4	4	5.88	64	6i.fi	65.25	48	1.25
	mm	1752.6	1619.3	1714.5	1581.1	79.2	101.6	101.6	149.4	1625.6	1695.4	1657.3		31.8
66	in.	75	69.75	73.5	68.5	4	4.38	4.38	6.88	70	72.75	71.25	56	1.25
	mm	1905	1771.6	1866.9	1739.9	101.6	111.3	111.3	174.8	1778	1847.8	1809.8		31.8
72	in.	81	75.75	80 00	74.5	5	5	5	8	76.5	78.75	77.75	64	1.25
	mm	2057.4	1924.1	2032 0	1892.3	127	127	127	203.2	1943.1	2000.3	1974.8		31.8

(1) Bore diameter to be specified by purchaser.