TORQUE CHART
Hi-Strength Metric Fasteners
Bowmetric® 12.9
Property Class 10.9
High-Strength Alloy Steel
Property Class 8.8
Medium Carbon Alloy Steel
Bowma-Grip Lock Nuts
Metric Prevailing-Torque Type
Medium Carbon Steel
Meets ASTM F568
Property Class 12.9 Specifications
Lubricated Threads
Dry Threads
Dia.
Ft.-Lbs.
(In.-Lbs.)
[Input Torque
Ft.-Lbs.]
Pre-Lubricated
For Use on Property Class
8.8, 10.9 or 12.9 Bolts
Nm
Ft.-Lbs.
(In.-Lbs.)
[Input Torque
Ft.-Lbs.]
Lubricated Threads
Dry Threads
Nm
Dia.
Ft.-Lbs.
(In.-Lbs.)
[Input Torque
Ft.-Lbs.]
Nm
Ft.-Lbs.
(In.-Lbs.)
[Input Torque
Ft.-Lbs.]
Nm
Dia.
Ft.-Lbs.
(In.-Lbs.)
[Input Torque
Ft.-Lbs.]
Ft.-Lbs.
(In.-Lbs.)
[Input Torque
Ft.-Lbs.]
Nm
Nm
M4
4‡
2.3‡
5.1
(48)
s
(30)
q
3.1
M4
3‡
2‡
4.5
(40)
s
(23)
q
2.6
M4
2‡
1‡
3.4
1.8
(30)
q
(16)
q
M5
8‡
4.6‡
10.3
(98)
s
(58)
s
6.2
M5
7‡
4‡
8.8
(78)
s
(46)
s
5.2
M5
5‡
3‡
6.4
(56)
s
(34)
s
M6
13‡
8‡
17.5
10.5
(165)
l(100)
s
M6
11‡
7‡
15.2
(134)
s
(80)
s
9
M6
8‡
5‡
10.6
(94)
s
(56)
s
M8
32‡
19‡
43
(405)
l(245)
l
26
M7
19‡
11‡
25.5
15.2
(225)
l(134)
s
M7
13‡
8‡
17.6
10.6
(155)
l
(94)
s
50
M8
27‡
16‡
36.5
(325)
l(195)
l
M8
19‡
11‡
25.5
15.4
(225)
l(136)
s
M10
53‡
32‡
72.5
43.5
(640)
l(385)
l
M10
37‡
22‡
51
30.5
(450)
l(270)
l
M10
62 n
85
37‡
(480)l
22
Class 12.9
Lubricated Threads
Dry Threads
Dia.
Ft.-Lbs.
(In.-Lbs.)
[Input
Torque
Ft.-Lbs.]
Nm
Class 10.9
Ft.-Lbs.
(In.-Lbs.)
[Input
Torque
Ft.-Lbs.]
Class 8.8
Nm
Ft.-Lbs.
(In.-Lbs.)
[Input
Torque
Ft.-Lbs.]
Nm
2‡
1‡
M4
3
(22)q(17)
q
2
1 ‡
(12) q2
3.8
4‡
3‡
M5
5
(44)s(34)
s
4
2 ‡
(26) q3
6.4
6‡
5‡
M6
8
(76)s(60)
s
7
4 ‡
(42) s5
10‡
8‡
M7 (124)s(100)
14.2
s
11.4
6 ‡
(70) s8
14‡
12‡
M8 (180)l(146)
19.2
s
17
9 ‡
(102) s12
28‡
24‡
M10 (340)l(290)
38
l
33
17 ‡
(205) l23
49‡
42‡
M12 (625)l(505)
66
l
57
29 ‡
(350) l40
90
47 ‡
(590) l63
M12
108
n
14765
n88
M14
173
n
234104
n140
M16
270
u
366162
n220
M12
93 n
126
M18
370
u
503223
n302
M14
148
n
20090
n121
M14
104
n
14062
n84
M20
525
u
713316
u428
M16
231
n
315140
n188
M16
162
n
22097
n131
M14
78 n
105
66 n
M18
317
u
430190
n258
M18
230
n
310138
n187
M16
121 n
165104
n14173
n98
M20
450
u
610270
u365
M20
325
u
440195
n265
M18
167 n
225144
n 195104
n140
M24
565
u
765340
u460
M20
237 u
320202
n 274146
n198
410 u
555350
u 475253
u343
[253]
u
M24
1233
909
✚
545 u
740
56‡
(670)l
[501]
u
[301]
u
M30
2449
1806
✚
1084 ✚
1470
[225]
u
[135]
u
✚
✚
M36
4280
★
1894 ★
3157
[216]
u
M24
1055
778
✚
2568
[430]
u
[260]
u
M30
2095
1548
✚
929 ✚
467 u
[195]
u
[450]
u
✚
M36
3667
2705
★
1623 ✚
75.5
633
1260
2200
M12
65 n
88
39‡
(470)l
53
[310]
u
[185]
u
M30
1515
1119
✚
670 ✚
910
M24
[545]
u
[325]
u
M36
2650
1955
✚
1173 ✚
1590
[226]u
[195]u
M30
1102
813✚702
✚
952503
u682
[394]u
[340]u
M36 1420✚1224
1925
✚
1660
[244] u
878 ✚1191
Guidelines For the Use of This Chart
Torque values are intended only as guidelines for fastener users. Many variables, including
environment, affect actual clamp loads. When a precise clamp load is critical to assembly, it
is the responsibility of the installer to determine exact torque values with the use of proper
instrumentation. These specifications are the recommeded assembly torques for various
property classes of Barnes metric threaded fasteners with the following qualifications:
1. Torque values are calculated at 75% of proof load for Property Classes 8.8 and 10.9, and at
80% for Property Class 12.9. This provides a design safety factor.
2. All dry torque values are given for the “as received” condition, Unichrome™ (zinc) plated
hex head cap screws.
3. Lubricated torque values are calculated based on applying Barnes Distribution Anti-Seize
Compound to the threads before assembly. (Note: This is the recommended approach
because it permits lower torque values and results in less clampload scatter.)
q
Micrometer Adjustable
Torque Wrench Available
through Barnes Industrial
Supply Division
Capacity 10-15 In.-Lbs.
1/4” Drive
With Ratchet Head
Explanation of Symbols
The symbols to the right of the recommended torque value represent the torque wrench and torque multiplier(s)
(when applicable) recommended for proper installation. In those instances where two torque values are listed, the
symbol(s) corresponds to the torque value shown in parenthesis ( ) or brackets [ ].
6. [Input Torque] is the setting for the 3/4” drive torque wrench, Barnes Distribution Part No.
19813, that will produce the final torque required through the torque multiplier(s). The
torque value shown below the bracketed [ ] input torque is the foot-pound torque value
developed through the use of a multiplier(s).
7. All torque values are based on standard thread pitch fasteners.
K-982 8/13
1. For critical applications, use a beam-pointer type torque wrench. Tighten several bolts
until the pointer stops rising. Record the maximum torque achieved for each bolt.
Averaging the recorded results, torque new assemblies to 75% of the average value.
2. Due to the many variables that affect friction, it is possible to experience as much as
±25% deviation in preload (clampload) with the use of a torque wrench.
s
✚
Micrometer Adjustable
Torque Wrench
Barnes Part No. 19810
Capacity 30-150 In.-Lbs.
3/8” Drive
With Ratchet Head
Torque Multiplier
Available through Barnes
Industrial Supply Division
Max. Torque 2000 Ft.-Lbs.
Input Drive Size 3/4”
Output Drive Size 1”
Ratio of Gears 3.6 - 1
(Gear Friction Factored)
4. Special torque values are given when using the Bowma-Grip® Lock Nut because of its
highly efficient pre-lubricated coating. Use these values only when using the Bowma-Grip®
Lock Nut.
5. All torque values are based on the use of through-hardened flat washers under the bolt
head and nut, or only under the bolt head in a tapped and chamfered hole application.
This provides a uniform, hard, smooth bearing surface.
NOTES:
l
Micrometer Adjustable
Torque Wrench
Barnes Part No. 19811
Capacity 150-750 Ft.-Lbs.
3/8” Drive
With Ratchet Head
‡
n Micrometer Adjustable
Torque Wrench
Barnes Part No. 19812
Capacity 50-250 Ft.-Lbs.
1/2” Drive
With Ratchet Head
★
u Micrometer Adjustable
Torque Wrench
Barnes Part No. 19813
Capacity 100-600 Ft.-Lbs.
3/4” Drive
With Ratchet Head
Torque Multiplier
Available through Barnes
Industrial Supply Division
Max. Torque 4000 Ft.-Lbs.
Input Drive Size 1”
Output Drive Size 1-1/2”
Ratio of Gears 3.9 - 1
(Gear Friction Factored)
Bowmetric® and Bowma-Grip® are registered trademarks of MSC Industrial Supply Co.
Unichrome™ is a trademark of MSC Industrial Supply Co.
Installation with an inch-pound torque wrench is recommended. Inch-pound torque
value is listed in parenthesis.
www.BarnesDistribution.com
*Manufacturer’s identification symbol is required by American Society for Testing and
Materials (ASTM), International Organization for Standardization (ISO) and/or Society
of Automotive Engineers (SAE).
866-GET-MROP
K-982 8/13
www.BarnesDistribution.com
866-GET-MROP
Torque Chart
Hi-Strength Metric Fasteners