Bosch GDS 24 Professional Manual Original página 13

OBJ_BUCH-548-002.book Page 13 Friday, September 6, 2013 9:43 AM
– A soft seat is given for screw applications, e. g., metal on
wood or when using lead washers or fibre washers as back-
ing.
For a spring-loaded seat as well as for a soft seat, the maxi-
mum tightening torque is lower than for a hard seat. Also, a
clearly longer impact duration is required.
Diagram for GDS 24
[Nm]
The highest torque is achieved:
– for a hard seat after approx. 10 seconds of impact
– for a soft seat after approx. 22 seconds of impact
Reference Values for Maximum Screw/Bolt Tightening Torques
Calculated from the tensional cross-section; utilization of the yield point 90 % (with friction coefficient μ
measure, always check the tightening torque with a torque wrench.
Property Classes ac- Standard Screws/Bolts
cording to DIN 267
3.6
M 8 6.57
M 10 13
M 12 22.6
M 14 36
M 16 55
M 18 75
M 20 107
M 22 145
M 24 185
M 27 275
M 30 370
Bosch Power Tools
Determining the Impact Duration
The diagrams (examples) indicate that the tightening torque
[Nm] depends on the impact duration [s]:
 For a hard seat
 For a soft seat.
The data are mean values and vary depending on the applica-
tion. As a control measure, always check the tightening
torque with a torque wrench.
Diagram for GDS 30
[Nm]
1
2
[s]
The highest torque is achieved:
– for a hard seat after approx. 6 seconds of impact
– for a soft seat after approx. 26 seconds of impact
For reference values for the maximum tightening torques of
commercially available screw/bolts, see the following table.
4.6 5.6 4.8 6.6
8.7 11 11.6 13.1
17.5 22 23 26
30 37.6 40 45
48 60 65 72
73 92 98 110
101 126 135 151
143 178 190 214
190 240 255 290
245 310 325 370
365 455 480 445
495 615 650 740
= 0.12). As a control
total
High-strength Bolts
5.8 6.8 6.9 8.8
14.6 17.5 19.7 23
29 35 39 47
50 60 67 80
79 95 107 130
122 147 165 196
168 202 227 270
238 286 320 385
320 385 430 510
410 490 455 650
605 725 815 960
820 990 1110 1300
3 609 929 C78 | (6.9.13)
English | 13
1
2
[s]
10.9 12.9
33 39
65 78
113 135
180 215
275 330
380 450
540 635
715 855
910 1100
1345 1615
1830 2200