Hilti DD 350-CA Mode D'emploi page 41

6.5.2 Wet drilling using a water collection system
and wet-type vacuum cleaner 15
NOTE
Wet-type vacuum cleaners are available as accessories.
CAUTION
Make sure that the core bit is centered within the
water collector.
NOTE
Use of the water collection system is not possible when
drilling at an angle.
NOTE
The diamond core bit fills with water when drilling over-
head. After overhead drilling, first drain the remaining
water from the core bit.
NOTE
The vacuum cleaner must be switched on manually be-
fore opening the water supply valve and switched off
again manually after closing the water supply valve.
NOTE
If the optional water flow indicator is not used, the water
flow when drilling overhead can be monitored only after
the core bit has filled with water.
The wet-type vacuum cleaner must be switched on.
Setting it to automatic mode is not permissible.
6.5.2.1 Starting the hole
1. Switch on the water supply.
2. Open the water flow regulator slowly until the desired
water flow rate out of the core bit is achieved.
WARNING The rotating core bit presents a risk of
3.
injury! A rotating core bit that is lowered toward
the base material is capable of severing parts of the
body. After fitting the core bit, adjust the system in
order to reduce the distance between the core bit
and the base material to a minimum before switching
on the diamond coring machine.
Bring the core bit as close as possible to the
surface in which the hole is to be drilled. However,
it should not touch the surface.
4. Press the "On" switch on the core drilling machine.
The core bit begins to rotate.
5. Release the carriage locking mechanism while hold-
ing the hand wheel securely.
6. Turn the hand wheel until the diamond core bit is in
contact with the work surface.
7. When starting the hole, apply only light pressure
until the diamond core bit has centered itself.
NOTE When the pressure applied is low, the drilling
performance indicator lights orange.
8. Increase the pressure applied to the core bit until
the drilling performance indicator lights green.
6.5.3 Dry drilling
To extract the drilling dust use a suitable dust removal
system consisting of a water collector and seal of the
correct, corresponding diameter (available as accessor-
ies), the appropriate connector and a vacuum cleaner.
The dust extraction process must be assisted by a flow
of compressed air through the core bit. The air flow rate
for this purpose must be at least 30 l/s.
NOTE
Wear respiratory protection when working in dusty con-
ditions.
The dust removal system and the compressed air supply
must be switched on.
6.5.3.1 Starting a hole using the dry drilling
technique
1. Set the 3-way valve on the core drilling machine to
"Dry drilling".
2. Open the water drainage plug so that the cooling
water can flow out.
3. Switch on the water supply.
4. Open the water flow regulator slowly until the desired
water flow rate out of the water drainage outlet is
achieved.
5. WARNING The rotating core bit presents a risk of
injury! A rotating core bit that is lowered toward
the base material is capable of severing parts of the
body. After fitting the core bit, adjust the system in
order to reduce the distance between the core bit
and the base material to a minimum before switching
on the diamond coring machine.
Bring the core bit as close as possible to the
surface in which the hole is to be drilled. However,
it should not touch the surface.
6. Press the "On" switch on the core drilling machine.
The core bit begins to rotate.
7. Release the carriage locking mechanism while hold-
ing the hand wheel securely.
8. Turn the hand wheel until the diamond core bit is in
contact with the work surface.
9. When starting the hole, apply only light pressure
until the diamond core bit has centered itself.
NOTE When the pressure applied is low, the drilling
performance indicator lights orange.
10. Increase the pressure applied to the core bit until
the drilling performance indicator lights green.
6.6 Completing the drilling operation 16
CAUTION
Heavy cores present a risk of injury. Take great care when
handling heavy cores. Be careful to avoid getting your
fingers trapped and crushed. Use a lifting aid or obtain
help.
1. Press the "Off" switch on the core drilling machine.
2. Turn the hand wheel to lift the diamond core bit out
of the hole.
3. Lock the carriage in position.
NOTE The carriage is locked when the locking pin
is engaged.
In this position, no movement of the carriage is
possible.
en
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