Komatsu 730E - Page 21

OM1200 02/11 Torque Tables And Conversion Charts - Section 12
Page 12-3
STANDARD TIGHTENING TORQUES
For SAE Grade 5 and Grade 8 Cap screws
The following specifications apply to required assem-
bly torques for all grade 5 and grade 8 cap screws.
• Cap screw threads and seats shall be lubricated
when assembled.
Unless instructions specifically recommend
otherwise, these standard torque values are to
be used with simple lithium base chassis grease
(multi-purpose EP NLGI) or a rust- preventive
grease (see list, previous page) on the threads.
• Torques are calculated to give a clamping force
of approximately 75% of proof load.
• The maximum torque tolerance shall be ±10% of
the torque value shown.
• In the following table under Cap Screw Size, the
first number represents the shank diameter (in.).
The second number represents threads per inch.
Example: 7/16 - 20
7/16 = shank diameter (7/16 inch (0.438 inch))
20 = threads per inch
TABLE 2.
Standard Tightening Torque
for SAE Hex Head Cap Screw And Nut Assembly
Cap
Screw
Size
Torque -
Grade 5
Torque -
Grade 8
Cap
Screw
Size
Torque -
Grade 5
Torque -
Grade 8
N·m ft lb kg·m N·m ft lb kg·m N·m ft lb kg·m N·m ft lb kg·m
1/4-20 9.5 7 0.97 13.6 10 1.38 3/4-16 319 235 32.5 454 335 46.3
1/4-28 10.8 8 1.11 14.9 11 1.52 7/8-9 475 350 48.4 678 500 69.2
5/16-18 20.3152.0728 212.907/8-14 508 375 51.9 719 530 73.3
5/16-24 22 16 2.21 30 22 3.04 1.0-8 712 525 72.6 1017 750 103.7
3/8-16 34 25 3.46 47 35 4.84 1.0-12 759 560 77.4 1071 790 109.3
3/8-24 41 30 4.15 54 40 5.5 1.0-14 773 570 78.8 1085 800 110.6
7/16-14 54 40 5.5 79 58 8.0 1 1/8-7 881 650 89.9 1424 1050 145
7/16-20 61 45 6.2 84 62 8.57 1 1/8-12 949 700 96.8 1546 1140 158
1/2-13 88 65 9 122 90 12.4 1 1/4-7 1234 910 125.9 2007 1480 205
1/2-20 95 70 9.7 129 95 13.1 1 1/4-12 1322 975 134.8 2142 1580 219
9/16-12 122 90 12.4 169 125 17.3 1 3/8-6 1627 1200 166 2630 1940 268
9/16-18 129 95 13.1 183 135 18.7 1 3/8-12 1776 1310 181 2874 2120 293
5/8-11 169 125 17.3 237 175 24.2 1 1/2-6 2142 1580 219 3471 2560 354
5/8-18 183 135 18.7 258 190 26.2 1 1/2-12 2305 1700 235 3756 2770 383
3/4-10 298 220 30.4 420 310 42.8
1 ft. lb. = 0.138 kg·m = 1.356 N.m