Method Of Operation; Switching On And Off - Bosch GDS 30 PROFESSIONAL Bedienungsanleitung

3 609 929 345 - Buch Seite 2 Freitag, 5. Dezember 2003 12:16 12

Method of Operation

The tool holder 6 with the tool is driven by an
electric motor via a gear and impact mechanism.
The working procedure
two phases:
Screwing in and tightening (impact mechanism
in action)
The impact mechanism is activated as soon as
the screwed connection runs tight and load is put
on the motor. In this instance the impact mecha-
nism converts the power of the motor to steady
rotary impacts. When loosening screws, the proc-
ess is reversed.
Initial Operation
Observe correct mains voltage: The voltage of
the power source must agree with the voltage
specified on the nameplate of the machine.
Equipment marked with 230 V can also be con-
nected to 220 V.

Switching On and Off

To start the machine, press the On/Off switch 4
and keep it depressed.
To switch off the machine, release the On/Off
switch 4.
Reversing the Rotational Direction
The required direction of rotation is selected by
pushing the rotational direction switch 5.
Operate the rotational direction switch 5
only at a standstill.
Operating Instructions
The impact wrench is equipped with a square
drive 6 for all common tool inserts.
Set the machine against the screw /nut only when
switched off.
For safety reasons, the impact wrench may be
used only with the auxiliary handle 2.
The torque depends on the impact duration. The
maximum torque results from all the individual
torques which have been produced by impacts.
The maximum torque is reached after an impact
duration of 6 to 10 seconds. After this duration
the tightening torque increases only very little, but
the gear casing warms up noticeably.
12 • 3 609 929 345 • 03.12
The effects of excessive warming up are high
wear on all impact mechanism components
and high lubricant requirement.
The impact duration is to be determined for each
required tightening torque. The actually achieved
is divided into
tightening torque is always to be checked with a
torque wrench.
Screw Applications with Hard,
Spring-loaded or Soft Seat
When in a test, the achieved torques in an impact
series are measured and transferred into a dia-
gram, the result is the curve of a torque charac-
teristic. The height of the curve corresponds with
the maximum reachable 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 bolts/nuts
– Type of backing (washer, disc spring, seal)
– Strength properties of the material being
screwed/bolted together
– Lubrication conditions at the screw /bolt con-
nection
The following application cases result accord-
ingly:
A hard seat is given for metal to metal screw ap-
plications with the use of washers. After a rela-
tively short impact duration, the maximum torque
is reached (steep characteristic curve). Unneces-
sary 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 bolts /nuts
with conical seat as well as when using exten-
sions.
A soft seat is given for screw applications, e. g.,
metal on wood or when using lead washers or fi-
bre 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 impact duration
is required.
English - 2