Bosch Professional GDS 18V-1600 HC Original Instructions Manual page 10

10 | English
Status indicator for power Meaning/cause
tool (11)
Flashing blue Power tool is connected to a mobile device or
settings are being transferred
Speed preselection
With the speed preselection button (15), you can preselect
the required speed in three stages. Press button (15) as of-
ten as needed until the required setting is indicated in the
speed indicator (16). The selected setting will be saved.
You can also preselect the speed using the Bosch Toolbox
app.
The required speed depends on the material and the work-
ing conditions; it can be ascertained through practical tests.
The information in the table below describes the recommen-
ded values.
Basic speed setting at level
1
[min
Number of speed settings
3
You can use the button for speed preselection (15) to
preselect the required speed, even during operation.
Selecting the working mode
The power tool has two preset working modes A and B (12).
You can also programme working modes for different applic-
ations and adjust existing modes via the Bosch Toolbox un-
der A and B (12).
To switch between the working modes A and B (12), press
button (13).
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 power tool with inserted Bluetooth
u
Module GCY 42 (accessory) is equipped with a radio
interface. Local operating restrictions, e.g. in aircraft
or hospitals, must be observed.
Guide values for maximum screw tightening torques
Figures given in Nm; calculated from the tensional cross-section; utilization 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 accord-
ing to DIN EN ISO 898
M16
M18
M20
M22
M24
M27
M30
1 609 92A 8EC | (08.09.2023)
2 3
–1 –1 –1
] [min ] [min ]
0–800 0–1300 0–1750
®
Low Energy
Standard screws
3.6 4.6 4.8/5.6
57 76 96
80 106 133
112 150 187
151 202 252
193 257 322
284 379 474
386 515 644
Solution
–
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 increases only minimally.
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 with the maximum reachable torque, and the
steepness 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 reached (steep characteristic curve).
Unnecessary long impact duration only causes damage 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. Also, a
clearly longer impact duration is required.
High-strength screws
6.8 8.8
153 206
212 295
300 415
403 567
515 714
759 1050
1031 1428
10.9 12.9
302 354
421 492
592 692
807 945
1017 1190
1496 1750
2033 2380
Bosch Power Tools