Bosch PDR 18 LI Notice Originale page 14

14 | English
To switch off the power tool, release the on/off switch (6).
Adjusting the speed
You can adjust the speed of the power tool when it is on by
pressing in the on/off switch (6) to varying extents.
A light pressure on the on/off switch (6) results in a low rota-
tional speed. Increased pressure on the switch causes an in-
crease in speed.
Temperature-dependent overload protection
In normal conditions of use, the power tool cannot be over-
loaded. If the power tool is overloaded or the permitted bat-
tery temperature is exceeded, the electronics of the power
tool will switch off until the temperature returns to within the
optimum operating temperature range.
Protection against deep discharge
The lithium-ion battery is protected against deep discharge
by the Electronic Cell Protection (ECP). When the battery is
discharged, the power tool is switched off by means of a pro-
tective circuit: The application tool no longer rotates.
Practical advice
Only apply the power tool to the screw/nut when the
u
tool is switched off. Rotating tool inserts can slip off.
The torque depends on the impact duration. The maximum
achieved torque results from the sum of all individual
torques achieved through impact. Maximum torque is
achieved after an impact duration of 6–10 seconds. After
this duration, the tightening torque is increased only minim-
ally.
Reference values for maximum screw/bolt tightening torques
Figures given in Nm; calculated from the tensional cross-section; utilisation of the yield point: 90% (with friction coefficient
μ = 0.12). As a control measure, always check the tightening torque with a torque wrench.
total
Property classes ac- Standard screws/bolts
cording to DIN 267
3.6
M 6 2.71
M 8 6.57
M 10 13
M 12 22.6
M 14 36
M 16 55
Tips
Before screwing larger, longer screws into hard materials, it
is advisable to predrill a pilot hole with the core diameter of
2
the thread to approx. / of the screw length.
3
1 609 92A 49G | (07.09.2018)
The impact duration is to be determined for each required
tightening torque. The tightening torque actually achieved
should always be checked with a torque wrench.
Screw applications with hard, spring-loaded or soft seats
When the achieved torques in an impact series are measured
during a test and transferred into a diagram, the result is the
curve of a torque characteristic. The height of the curve cor-
responds to the maximum achievable torque, and the steep-
ness indicates the duration in which this is achieved.
A torque gradient depends on the following factors:
– Strength properties of the screws/nuts
– Type of backing (washer, disc spring, seal)
– Strength properties of the material being screwed/bolted
together
– Lubrication conditions at the screw/bolt connection
The following application cases result accordingly:
– A hard seat is a metal-to-metal screw application which
uses washers. After a relatively short impact duration, the
maximum torque is achieved (steep characteristic curve).
An unnecessarily long impact duration only causes dam-
age to the machine.
– A spring-loaded seat is also a metal-to-metal screw ap-
plication but uses spring washers, disc springs, studs or
screws/nuts with conical seats. It is also called a spring-
loaded seat when extensions are used.
– A soft seat is a screw application of e.g. metal on wood or
a screw application that uses lead washers or fibre wash-
ers as backing.
For a spring-loaded seat, as well as for a soft seat, the max-
imum tightening torque is lower than for a hard seat. A much
longer impact duration is also required.
4.6 5.6 4.8 6.6
3.61 4.52 4.8 5.42
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
Maintenance and Servicing
Maintenance and cleaning
Remove the battery from the power tool before carry-
u
ing out work on the power tool (e.g. maintenance,
changing tool, etc.). The battery should also be re-
moved for transport and storage. There is risk of injury
from unintentionally pressing the on/off switch.
5.8 6.8 6.9 8.8
6.02 7.22 8.13 9.7
14.6 17.5 19.7 23
29 35 39 47
50 60 67 80
79 95 107 130
122 147 165 196
High-strength
bolts
10.9 12.9
13.6 16.2
33 39
65 78
113 135
180 215
275 330
Bosch Power Tools