| Operating techniques |
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A fundamental requirement
for efficient material breakage is that the tool
always works perpendicular to the object that is to
be demolished.
Keep the tool at a 90 degree angle to the workpiece
at all times. If the workpiece moves or the surface
is demolished, correct the angle of the tool
immediately. Use the boom of the carrier to keep a
constant feeding force behind the breaker when it is
operating. This will ensure that the tool is thrust
into the material with constant force. |
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| If the feeding force is
too low, the breaker will not be fully effective.
Mechanical vibrations will then be transmitted to
the excavator itself. |
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| Do not apply more feeding
force to the breaker than necessary. If the carrier
begins to lift itself from the ground to much force
has been used and this will create unwanted forces
on the tool and bushing. |
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| When the breaker is
working at its most efficient position, the
vibrations will be at a minimum. |
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| Do not start in the
middle of a large workpiece. |
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The breaker
should not work on the same point for more than 15
seconds. If the object resists demolition, move the
tool to another position.
Avoid idle percussion. Idle percussion causes rapid
wear of the tool retainer and the shank of the tool.
If possible, try to stop the breaker before the tool
breaks through the workpiece. |
| Keep in mind that the
breaker is a percussive tool, not a levering tool.
The wrong way of working causes increased wear of
the bushings. Worn bushings in turn increase the
stresses on the tool and on the striking surface of
the piston. Working with the tool against a surface
that isn’t perpendicular to the breaker can very
easily lead to severe fracture forces in the tool,
which may break as a result. |
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| Avoid running the
cylinders all the way to their end positions as this
will cause unnecessarily high vibrations and wear of
the carrier. |
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| When breaking asphalt,
wide chisels or asphalt tools should be used. For
optimum efficiency, remember to apply the breaker at
an angle as close to 90 degrees as possible. Wide
chisel tools and asphalt tools are available in
versions with the blade parallel to the machine or
indexed 90 degrees which can be an advantage when
re-positioning is difficult or impossible. |
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Special Applications |
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| When scaling in tunnels
is it important that the breaker is angled away from
the carrier arm. This will prevent falling rock from
hurting the operator or damaging the carrier. For
information regarding necessary extra equipment and
safety instructions please contact Atlas Copco. |
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| When working in water,
even if only the front end is under the surface of
the water, the breaker must be supplied with
pressurised air. Please contact Atlas Copco for more
information regarding extra equipment and safety
instructions. |
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Keep an eye
on
THE PRESSURE HOSE: Abnormal vibrations of the
pressure hose is an indication the gas pressure of
the accumulator is too low. See the technical
documentation for correct pressure for all Atlas
Copco hydraulic breakers.
THE TOOL: To obtain full efficiency from the
breaker the tool must be able to move freely in the
bushing. The easiest way to check this is to lift
the breaker. The tool should then drop toward the
tool retainer.
THE ENGINE SPEED: Match the speed of the
diesel engine to the hydraulic pressure. Excessive
engine speed will only result in excessive heat and
fuel consumption.
THE OIL TEMPERATURE: If the oil temperature
exceeds 176º F/80º C (or the maximum temperature
recommended by the oil manufacturer) the breaker
should be stopped. If this happens regularly an
extra oil cooler may have to be installed.
If the oil temperature is below 14º F/-10º C the
breaker has to be pre-heated before starting. |
Choose the correct
tool
For demolition work that requires penetration and
splitting in soft materials, a moil point or chisel
(narrow or wide) that bites through the material
should be used.
For work in hard materials that requires cracking,
like boulders or hard concrete a blunt tool should
be used for the best effect.
Wide chisels and asphalt cutters are designed for
fine cuts in soft materials. |
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Tool
damage
Idle percussion or insufficient lubrication causes
wear on the tool shank and tool retainer.
The use of wide chisel or asphalt cutter on hard
surfaces may cause powerful torsional forces on the
tool, which may damage not only the cutting edge of
the tool but also the tool retainer and tool shank.
Operating in cold ambient temperatures, below 14° F
/ -10° C, may cause em-brittlement fracture of the
tool. This can be prevented by heating the tool
before starting to use the breaker. |
| The tool will wear
quickly if it overheats. The striking surface
becomes mushroom shaped and brittle. Therefore,
avoid long percussion periods. |
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| Typical fracture damage
gives just a few rings on the side of the fracture
surface. |
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Fatigue damage gives a
pattern of rings over a large part of the fracture
surface.
Both these fractures are caused by excessive bending
with the tool, i.e. an incorrect handling of the
machine. |
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| Since the
tools have been specially hardened they may not be
reforged. However, grinding or machining is
permitted. |
Lubrication |
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| The tool
shank must always be well lubricated. The grease
tends to ‘dry up’ during operation and must
therefore be re-applied regularly. Adapt the
quantity of grease and the lubrication intervals to
suit the kind of work being done and the wear
characteristics of the tool and tool bushing.. |
Lubrication by hand
using a grease gun
Grease the tool generously every second hour with
Atlas Copco Tool Shank Grease.
During lubrication the tool must be pressed against
the piston so that the space between the piston and
the tool does not get filled with grease. |
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| Whenever a
tool is inserted into the breaker, make sure that
the bushing and the tool shank are well greased to
avoid damages on the breaker. This is especially
important when installing a new tool. |
Central lubrication
Lubrication will be considerably more effective if a
central lubrication system is fitted on the carrier.
All Atlas Copco hydraulic breakers except SBC 60
have been prepared for this kind of lubrication
system which removes the need for lubrication
breaks. This in turn saves operating time and raises
the efficiency of the breaker. Central lubrication
also increases the life length of the tool bushings
and tools considerably. When the central lubrication
is fitted, grease is pumped continuously from a
lubrication container on the carrier to the breaker
when the breaker is activated. |
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Advice on maintenance
Check and clean the hose connections before fitting
or removing the breaker form the carrier. |
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| Always plug or cap hoses
and nipples as soon as they are disconnected. Bear
in mind that the hydraulic oil may be hot. |
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WARNING!
Always switch off the engine before
starting any work on the breaker, its
connections, or hoses.
Remember that the tool for the breakers are
heavy. Take great care and use suitable
lifting equipment when fitting or removing a
tool from the breaker.
The utmost care must be taken when fitting
the breaker to the carrier. Any movement of
the boom or dipper must be made in
conjunction with the instructions from the
person fitting the breaker. |
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