Common Flange Specifications

By Type (*)

Flange Name	Flange I.D. (max)	Flange O.D.	Bolt Circle	Bolt Hole	# of Bolts	# of Clamps	Bolt Size
NW 16 CF/Mini	0.630 (16)	1.33 (34)	1.063 (27)	0.169 (4.3)	6	None Required	832 x 3/4 (#)
NW 25 CF/2 1/8"	0.88 (22.2)	2.11 (53.6)	1.625 (41.3)	0.265 (6.7)	4	None Required	1/4-28 x 1 1/4 (#)
NW 35 CF/2 3/4"	1.500 (38.1)	2.75 (69.9)	2.312 (58.7)	0.265 (6.7)	6	None Required	1/4-28 x 1 1/4 (#)
NW 63 CF/4 1/2"	2.500 (63.5)	4.47 (113.5)	3.628 (92.2)	0.332 (8.4)	8	None Required	5/16-24 x 2 (#)
NW 75 CF/4 5/8"	2.88 (73)	4.62 (117.35)	4.030 (102.4)	0.332 (8.4)	10	None Required	5/16-24 x 2 (#)
NW 100 CF/6"	4.00 (101.6)	5.97 (151.6)	5.128 (130.3)	0.332 (8.4)	16	None Required	5/16-24 x 2 1/4 (#)
NW 130 CF/6 3/4"	4.87 (123.7)	6.75 (171.45)	5.969 (151.6)	0.332 (8.4)	18	None Required	5/16-24 x 2 1/4 (#)
NW 150 CF/8"	6.00 (152.4)	7.97 (202.4)	7.128 (181.1)	0.332 (8.4)	20	None Required	5/16-24 x 2 1/4 (#)
NW 200 CF/10"	8.00 (203.2)	9.97 (253.2)	9.128 (231.9)	0.332 (8.4)	24	None Required	5/16-24 x 2 1/2 (#)
NW 250 CF/12"	9.843 (250.0)	12.05 (306)	11.18 (284)	0.332 (8.4)	32	None Required	5/16-24 x 2 1/2 (#)
NW 275 CF/13 1/4"	10.63 (270)	13.25 (336.55)	12.06 (306.3)	0.390 (9.9)	30	None Required	3/8-24 x 2 1/2 (#)
NW 63 ISO-F	2.37 (60.20)	3.74 (95.0)	---	0.35 (8.9) (+)	4	4 (++)	M8 x 40
NW 80 ISO-F	2.87 (72.90)	4.33 (110)	---	0.35 (8.9) (+)	4	4 (++)	M8 x 40
NW 100 ISO-F	3.83 (97.28)	5.12 (130)	---	0.35 (8.9) (+)	4	4 (++)	M8 x 40
NW 160 ISO-F	5.87 (149.10)	7.09 (180)	---	0.43 (10.9) (+)	4	4 (++)	M10 x 50
NW 200 ISO-F	7.83 (198.90)	9.45 (240)	---	0.43 (10.9) (+)	6	6 (++)	M10 x 50
NW 250 ISO-F	12.42 (315.47)	14.57 (370)	---	0.43 (10.9) (+)	6	6 (++)	M10 x 50
NW 320 ISO-F	12.42 (315.47)	14.57 (370)	---	0.51 (13.0) (+)	8	8 (++)	M12 x 60
NW 400 ISO-F	15.50 (393.70)	17.72 (450)	---	0.51 (13.0) (+)	8	8 (++)	M12 x 60
NW 500 ISO-F	19.50 (495.30)	21.65 (550)	---	0.51 (13.0) (+)	12	12 (++)	M12 x 60
NW 63 ISO-Bolt Flange	2.37 (60.20)	5.12 (130)	4.331 (110)	M8	4	4	M8 x 40
NW 80 ISO-Bolt Flange	2.87 (72.90)	5.71 (145)	4.920 (125)	M8	4	4	M8 x 40
NW 100 ISO-Bolt Flange	3.83 (97.28)	6.496 (165)	5.709 (145)	M8	8	4	M8 x 40
NW 160 ISO-Bolt Flange	5.87 (149.10)	8.858 (225)	7.874 (200)	M10	8	4	M10 x 50
NW 200 ISO-Bolt Flange	7.83 (198.90)	11.22 (285)	10.236 (260)	M10	12	6	M10 x 50
NW 250 ISO-Bolt Flange	9.75 (247.65)	13.189 (335)	12.205 (310)	M10	12	6	M10 x 50
NW 320 ISO-Bolt Flange	12.42 (315.47)	16.732 (425)	15.551 (395)	M12	12	8	M12 x 60
NW 400 ISO-Bolt Flange	15.50 (393.70)	20.08 (510)	18.90 (480)	M12	16	8	M12 x 60
NW 500 ISO-Bolt Flange	19.50 (495.30)	24.02 (610)	22.83 (580)	M12	16	12	M12 x 60
1.5" ASA	2.200 (55.9)	5.00 (127.0)	3.875 (98.4)	0.62 (15.9)	4	None Required	1/2-13 x 1 1/2
2" ASA	3.00 (76.2)	6.00 (152.6)	4.750 (120.7)	0.75 (19.1)	4	None Required	5/8-11 x 1 3/4
3" ASA	4.20 (107)	7.50 (190.5)	6.00 (152.4)	0.75 (19.1)	8	None Required	5/8-11 x 1 3/4
4" ASA	5.70 (145)	9.00 (228.6)	7.500 (190.5)	0.75 (19.1)	8	None Required	5/8-11 x 1 3/4
6" ASA	7.6 (193)	11.0 (279.4)	9.500 (241.3)	0.81 (20.6)	8	None Required	3/4-10 x 2 1/4
8" ASA	10.276 (261.0)	13.50 (342.9)	11.750 (298.5)	0.81 (20.6)	8	None Required	3/4-10 x 2 1/4
10" ASA	12.00 (304.8)	16.00 (406.4)	14.250 (362)	0.81 (20.6)	12	None Required	3/4-10 x 2 1/4
16" ASA	18.00 (457.2)	23.50 (596.9)	21.25 (539.5)	1.12 (28)	16	None Required	7/8-9 x 3
20" ASA	21.25 (539.8)	27.50 (698.5)	25.00 (635)	1.25 (32)	20	None Required	18 x 3 1/2
30" ASA	32.125 (816)	38.00 (965)	36.25 (921)	0.88 (22)	16	None Required	3/4-10 x 3 1/4
35" ASA	35.0 (889)	41.75 (1060)	38.50 (978)	0.88 (22)	28	None Required	3/4-10 x 3 1/4

(*) All dimensions are in inches (mm).

(#) Thread size and bolt length are straight through - not tapped.

(+) Clamp clearance hole.

(++) Double claw clamps required.