Demco 91 - Torque Specifications

Page 4
Tighten all bolts to torques specified in chart unless otherwise noted. Check tightness of bolts
periodically, using bolt chart as guide. Replace hardware with same grade bolt.
NOTE: Unless otherwise specified, high-strength Grade 5 hex bolts are used throughout assembly
of equipment.
Bolt Torque for Standard bolts *
GRADE 2 GRADE 5 GRADE 8
A lb-ft (N.m) lb-ft (N.m) lb-ft (N.m)
1/4 6 (8) 9 (12) 12 (16)
5/16 10 (13) 18 (25) 25 (35)
3/8 20 (27) 30 (40) 45 (60)
7/16 30 (40) 50 (70) 80 (110)
1/2 45 (60) 75 (100) 115 (155)
9/16 70 (95) 115 (155) 165 (220)
5/8 95 (130) 150 (200) 225 (300)
3/4 165 (225) 290 (390) 400 (540)
7/8 170 (230) 420 (570) 650 (880)
1 225 (300) 630 (850) 970 (1310)
Torque figures indicated are valid for
non-greased or non-oiled threads and
heads unless otherwise specified.
Therefore, do not grease or oil bolts or
capscrews unless otherwise specified
in this manual. When using locking
elements, increase torque values
by 5%.
* GRADE or CLASS value for bolts
and capscrews are identified by their
head markings.
Torque Specifications
CLASS 8.8 CLASS 9.8 CLASS 10.9
A lb-ft (N.m) lb-ft (N.m) lb-ft (N.m)
6 9 (13) 10 (14) 13 (17)
7 15 (21) 18 (24) 21 (29)
8 23 (31) 25 (34) 31 (42)
10 45 (61) 50 (68) 61 (83)
12 78 (106) 88 (118) 106 (144)
14 125 (169) 140 (189) 170 (230)
16 194 (263) 216 (293) 263 (357)
18 268 (363) -- -- 364 (493)
20 378 (513) -- -- 515 (689)
22 516 (699) -- -- 702 (952)
24 654 (886) -- -- 890 (1206)
Bolt Torque for Metric bolts *
GRADE-2 GRADE-5 GRADE-8
8.8
10.9
9.8
CLASS 8.8 CLASS 9.8 CLASS 10.9