■ CAUTION ■
  • The special parts are excluded.
  • The bolts/nuts in these tables have a strength (discrimination) number/symbol assigned to the head or the like. As to the relation between the strength grade in these tables and the strength (discrimination) number/symbol, refer to “DISCRIMINATION OF BOLTS AND NUTS”.


 
 PREVIOUS STANDARD

Grade (Strength grade)
Bolt size
Bolt diameter
mm
Hexagonal width across flats
mm
Pitch
mm
Tightening torque (Without lubricant)
Hexagon head bolt
Hexagon flange bolt
N·m
kg-m
ft-lb
in-lb
N·m
kg-m
ft-lb
in-lb
4T
M6
6.0
10
1.0
5.5
0.56
4
49
7
0.71
5
62
M8
8.0
12
1.25
13.5
1.4
10

17
1.7
13

1.0
13.5
1.4
10

17
1.7
13

M10
10.0
14
1.5
28
2.9
21

35
3.6
26

1.25
28
2.9
21

35
3.6
26

M12
12.0
17
1.75
45
4.6
33

55
5.6
41

1.25
45
4.6
33

65
6.6
48

M14
14.0
19
1.5
80
8.2
59

100
10
74

7T
M6
6.0
10
1.0
9
0.92
7
80
11
1.1
8
97
M8
8.0
12
1.25
22
2.2
16

28
2.9
21

1.0
22
2.2
16

28
2.9
21

M10
10.0
14
1.5
45
4.6
33

55
5.6
41

1.25
45
4.6
33

55
5.6
41

M12
12.0
17
1.75
80
8.2
59

100
10
74

1.25
80
8.2
59

100
10
74

M14
14.0
19
1.5
130
13
96

170
17
125

9T
M6
6.0
10
1.0
11
1.1
8

13.5
1.4
10

M8
8.0
12
1.25
28
2.9
21

35
3.6
26

1.0
28
2.9
21

35
3.6
26

M10
10.0
14
1.5
55
5.6
41

80
8.2
59

1.25
55
5.6
41

80
8.2
59

M12
12.0
17
1.75
100
10
74

130
13
96

1.25
100
10
74

130
13
96

M14
14.0
19
1.5
170
17
125

210
21
155


■ CAUTION ■
The parts with aluminum or the cast iron washer surface/thread surface are excluded.
 
 NEW STANDARD BASED ON ISO

Grade (Strength grade)
Bolt size
Bolt diameter
mm
Hexagonal width across flats
mm
Pitch
mm
Tightening torque
Hexagon head bolt
Hexagon flange bolt
N·m
kg-m
ft-lb
in-lb
N·m
kg-m
ft-lb
in-lb
4.8
(Without lubricant)
M6
6.0
10
1.0
5.5
0.56
4
49
7
0.71
5
62
M8
8.0
13
1.25
13.5
1.4
10

17
1.7
13

1.0
13.5
1.4
10

17
1.7
13

M10
10.0
16
1.5
28
2.9
21

35
3.6
26

1.25
28
2.9
21

35
3.6
26

M12
12.0
18
1.75
45
4.6
33

55
5.6
41

1.25
45
4.6
33

65
6.6
48

M14
14.0
21
1.5
80
8.2
59

100
10
74

4.8
(With lubricant)
M6
6.0
10
1.0
4
0.41
3
35
5.5
0.56
4
49
M8
8.0
13
1.25
11
1.1
8

13.5
1.4
10

1.0
11
1.1
8

13.5
1.4
10

M10
10.0
16
1.5
22
2.2
16

28
2.9
21

1.25
22
2.2
16

28
2.9
21

M12
12.0
18
1.75
35
3.6
26

45
4.6
33

1.25
35
3.6
26

45
4.6
33

M14
14.0
21
1.5
65
6.6
48

80
8.2
59

8.8
(With lubricant)
M6
6.0
10
1.0
8
0.82
6
71
10
1.0
7
89
M8
8.0
13
1.25
21
2.1
15

25
2.6
18

1.0
21
2.1
15

25
2.6
18

M10
10.0
16
1.5
40
4.1
30

50
5.1
37

1.25
40
4.1
30

50
5.1
37

M12
12.0
18
1.75
70
7.1
52

85
8.7
63

1.25
70
7.1
52

85
8.7
63

M14
14.0
21
1.5
120
12
89

140
14
103

10.9
(With lubricant)
M6
6.0
10
1.0
10
1.0
7
89
12
1.2
9
106
M8
8.0
13
1.25
27
2.8
20

32
3.3
24

1.0
27
2.8
20

32
3.3
24

M10
10.0
16
1.5
55
5.6
41

65
6.6
48

1.25
55
5.6
41

65
6.6
48

M12
12.0
18
1.75
95
9.7
70

110
11
81

1.25
95
9.7
70

110
11
81

M14
14.0
21
1.5
160
16
118

180
18
133


■ CAUTION ■
  1. Use tightening torque with lubricant for the new standard bolts/nuts in principle. Friction coefficient stabilizer is applied to the new standard bolts/nuts.
  2. However, use tightening torque without lubricant for the following cases. Friction coefficient stabilizer is not applied to the following bolts/nuts.
    • Grade 4.8, M6 size bolt, Conical spring washer installed
    • Paint removing nut (Size M6 and M8) for fixing with weld bolt

 
 DISCRIMINATION OF BOLTS AND NUTS