Operating Instruction DX 351 (01)

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en
3. Technical description
The tool is designed for professional use in fastening
applications where specially-designed nails, threaded
studs and compo site fasteners are driven into concrete,
steel and sand-lime block masonry.
The tool works on the well-proven piston principle and
is therefore not related to high-velocity tools. The pis-
ton principle provides an optimum of working and fas-
tening safety. The tool works with cartridges of 6.8/11
caliber.
Piston return and cartridge transport is fully automatic.
This permits fastenings to be made very quickly and
economically with nails and threaded studs. The use of
a nail magazine (MX27 or MX32) greatly increases the
speed and convenience of fastening with the tool, above
all when making large numbers of identical fastenings
of all kinds.
As with all powder-actuated tools, the tool, magazine,
fastener program and cartridge program form a “tech-
nical unit”. This means that optimal fastening with this
system can only be achieved if the fasteners and car-
tridges are specially manufactured for it, or products of
equivalent quality, are used. The fastening and applica-
tion recommendations given by Hilti are only applicable
if these conditions are observed.
The tool features 5-way safety – for the safety of the
operator and bystanders.
The piston principle
The energy from the propellant charge is transferred to
a piston, the accelerated mass of which drives the fastener
into the base material. As approximately 95 % of the
kinetic energy is absorbed by the piston, the fastener is
driven into the base material at much reduced velocity
(less than 100 m/sec.) in a controlled manner. The dri-
ving process ends when the piston reaches the end of
its travel. This makes dangerous through-shots virtual-
ly impossible when the tool is used correctly.
The drop-firing safety device is the result of cou-
pling the firing mechanism with the cocking move-
ment. This is designed to prevent the Hilti DX tool from
firing when it is dropped onto a hard surface, no mat-
ter at which angle the impact occurs.
The trigger safety device ensures that the cartridge
cannot be fired simply by pulling the trigger only. The
tool can be fired only when fully depressed.
The contact pressure safety device requires the tool
to be fully depressed with a significant force. The tool
can be fired only when pressed fully in this way.
In addition, all Hilti DX tools are equipped with an unin-
tentional firing safety device . This prevents the tool
from firing if the trigger is pulled and the tool then pressed
against the work surface. The tool can be fired only when
it is first pressed 쩸 correctly and 쩹 the trigger then
pulled.
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2. General information
2.1 Signal words and their meaning
WARNING: The word WARNING is used to draw atten-
tion to a potentially dangerous situation which could
lead to severe personal injury or death.
CAUTION: The word CAUTION is used to draw attention
to a potentially dangerous situation which could lead to
minor personal injury or damage to the equipment or
other property.
2.2 Pictograms
Warning signs
General
warning
Warning:
hot surface
Obligation signs
Wear eye
protection
Wear a
safety helmet
Wear ear
protection
Symbols
Read the opera-
tion instructions
before use
 The numbers refer to the illustrations. The illustra-
tions can be found on the fold-out cover pages. Keep
these pages open while you read the operating instruc-
tions.
In these operating instructions, the designation “the
tool” always refers to the DX 351 powder-actuated tool.
Location of identification data on the tool
The type designation and the serial number are printed
on the type plate on the tool. Make a note of this infor-
mation in your operating instructions and always refer
to it when making an enquiry to your Hilti representa-
tive or service department.
Type: DX351 Serial no.: