Bosch Professional GDS 18 E Manual Original página 18

The following application cases result accord-
ingly:
– A hard seat is given for metal-to-metal screw
applications with the use of washers. After a
relatively short impact duration, the maxi-
mum torque is reached (steep characteristic
curve). Unnecessary long impact duration
only causes damage to the machine.
– A spring-loaded seat is given for metal-to-
metal screw applications, however with the
use of spring washers, disc springs, studs or
screws/nuts with conical seat as well as
when using extensions.
Reference Values for Maximum Screw/Bolt Tightening Torques
Calculated from the tensional cross-section; utilization of the yield point 90 % (with friction coeffi-
cient μ
= 0.12). As a control measure, always check the tightening torque with a torque wrench.
total
Property Classes
according to DIN 267
M6
M8
M10
M12
M14
M16
M18
M20
Tips
Torque rods have shanks with precisely calibrat-
ed, reduced diameters. Thus, they act torque-
limiting. A torque rod is placed between the im-
pact wrench and the bit.
Rule of thumb for the application: Core diame-
ter of the screw/bolt = effective diameter of the
torque rod. The impact duration is to be deter-
mined through practical testing.
The thumbwheel 6 must be set to max.
Bosch Power Tools
Standard Screws/Bolts
3.6 4.6 5.6
2.71 3.61 4.52
6.57 8.7 11
13 17.5 22
22.6 30 37.6
36 48 60
55 73 92
75 101 126
107 143 178
– A soft seat is given for screw applications,
e. g., metal on wood or when using lead
washers or fibre washers as backing.
For a spring-loaded seat as well as for a soft
seat, the maximum tightening torque is lower
than for a hard seat. Also, a clearly longer im-
pact duration is required.
4.8 6.6 5.8
4.8 5.42 6.02
11.6 13.1 14.6
23 26 29
40 45 50
65 72 79
98 110 122
135 151 168
190 214 238
For hanging up, a suspension hook 3 is mounted
at the machine's centre of gravity.
At temperatures below the freezing point, run
the machine for approx. 3 minutes at no-load to
improve its lubricating capacity.
English | 17
High-strength
Bolts
6.8 6.9 8.8
7.22 8.13 9.7
17.5 19.7 23
35 39 47
60 67 80
95 107 130
147 165 196
202 227 270
286 320 385
1 609 929 Y31 | (8.2.11)
10.9 12.9
13.6 16.2
33 39
65 78
113 135
180 215
275 330
380 450
540 635