Common Flange Specifications

By Size (*)

See Common Flange Specs by Type »
See legend below for explanations...

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 50 CF/3 3/8"

1.88 (47.6)

3.37 (85.6)

2.850 (72.4)

0.332 (8.4)

8

None Required

5/16-24 x 2 (#)

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

NW 63 ISO-F

2.37 (60.20)

3.74 (95.0)

---

0.35 (8.9) (+)

4

4 (++)

M8 x 40

NW 63 ISO-Bolt Flange

2.37 (60.20)

5.12 (130)

4.331 (110)

M8

4

4

M8 x 40

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 80 ISO-F

2.87 (72.90)

4.33 (110)

---

0.35 (8.9) (+)

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 75 CF/4 5/8"

2.88 (73)

4.62 (117.35)

4030 (102.4)

0.332 (8.4)

10

None Required

5/16-24 x 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

NW 100 ISO-F

3.83 (97.28)

5.12 (130)

---

0.35 (8.9) (+)

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 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 (#)

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

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 (#)

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

NW 160 ISO-F

5.87 (149.10)

7.09 (180)

---

0.43 (10.9) (+)

4

4 (++)

M10 x 50

NW 160 ISO-Bolt Flange

5.87 (149.10)

8.858 (225)

7.874 (200)

M10

8

4

M10 x 50

NW 150 CF/8"

6.00 (152.4)

7.97 (202.4)

7.128 (181.1)

0.332 (8.4)

20

None Required

3/16-24 x 2 1/4 (#)

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

NW 200 ISO-F

7.83 (198.90)

9.45 (240)

---

0.43 (10.9) (+)

6

6 (++)

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 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 ISO-F

12.42 (315.47)

14.57 (370)

---

0.43 (10.9) (+)

6

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 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 (#)

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

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 (#)

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

NW 320 ISO-F

12.42 (315.47)

14.57 (370)

---

0.51 (13.0) (+)

8

8 (++)

M12 x 60

NW 320 ISO-Bolt Flange

12.42 (315.47)

16.732 (425)

15.551 (395)

M12

12

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 400 ISO-Bolt Flange

15.50 (393.70)

20.08 (510)

18.90 (480)

M12

16

8

M12 x 60

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

NW 500 ISO-F

19.50 (495.30)

21.65 (550)

---

0.51 (13.0) (+)

12

12 (++)

M12 x 60

NW 500 ISO-Bolt Flange

19.50 (495.30)

24.02 (610)

22.83 (580)

M12

16

12

M12 x 60

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.