TM 1-1500-204-23-9
Figure 8-14. Type V Torque Wrench-Rigid Case, Preset Torque, Audible Signal
b. Reading the Torque Value. With the indicating
dial-type wrench, the torque value is read on the dial as
the force is applied. With the audible-indicating torque
wrench, the torque value is preset on the wrench by
releasing the lock in the end of the handle and rotating
the grip to the desired torque setting. When the preset
torque value is reached during the tightening operation,
the handle will automatically release or break, producing
approximately 15 to 20 degrees of free travel. This
release is distinct, easily detected by the mechanic, and
indicates completed torquing action on the fastener.
c. Use of Attachments and Extensions. Many torque
wrench applications will require the use of attachments
such as adapters and extensions to reach fasteners in
places of limited accessibility or to position the torque
wrench so that the dial is more easily read. In some
cases, the use of such attachments may greatly affect
the actual torque applied to the fastener.
(1) Concentric attachments. The use of an
attachment which operates in line with the drive square
of the wrench presents no particular problem, since the
effective length of the wrench is not lengthened or
shortened. The torque applied to the fastener will
therefore be the torque value indicated on the dial.
Figure 8-15 illustrates typical attachments of this type.
These attachments may also be used on the audible
indicating torque wrenches without affecting the torque
setting.
(2) Nonconcentric attachments.
For some
tightening applications, an attachment can be used on
the torque wrench that does not operate concentrically
with the drive square. An attachment of this type has
the effect of lengthening or shortening the lever length,
and the torque value shown on the dial is not the torque
that is applied to the fastener. When using these
attachments, it is necessary to calculate the effect of the
lever length to determine the correct torque reading.
Table 8-2. Recommended Torque Values
Fine Thread
Size
Plain &
Thin Plain &
and
Castellated Steel
Castellated Steel
Thread
Hex Nuts
Hex Nuts
Average
Average
8 - 36
12 - 15
7- 9
10- 32
20 -25
12 - 15
1/4 - 28
50 - 70
30 -40
5/16 - 24
100 - 140
60 - 85
3/8 - 24
160 - 190
95 - 110
7/16 - 20
450 - 500
270 -300
1/2 - 20
480 - 690
290 - 410
9/16 - 18
800 - 1000
480 - 600
5/8 - 18
1100 - 1300
600 - 780
3/4 - 16
2300 - 2500
1300 - 1500
7/8 - 14
2500 - 3000
1500 - 1800
1 - 14
3700 - 5500
2200 - 3300
11/8 - 12
5000 - 7000
3000 - 4200
11/4 - 12
9000 - 11000
5400 - 6000
Coarse Thread
8- 32
12 - 15
7- 9
10 -24
20 - 25
12 -15
1/4 - 20
40 - 50
25 - 30
5/16 - 18
80 - 90
48 - 55
3/8 - 16
160 - 185
95 - 100
7/16 - 14
235 -255
140 - 155
1/2 - 13
400 - 480
240 - 290
9/16 - 12
500 - 700
300 - 420
5/8 - 11
700 - 900
420 - 540
3/4 - 10
1150 - 1600
700 - 950
7/8 - 9
2200 - 3000
1300 - 1800
8-6
