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Start testing. Use the ignition pulse to heat the ignition wire until it
glows and ignites the powder.
A proven method for igniting explosives which are difficult to
ignite is as follows. Place one of the igniter sheets on the ignition
wire. Ideally, the explosive should be in sheets, 1 mm thick with
a edge length of 3 mm to 5 mm. Using a pin, make a small hole
in the sheet and place it in the middle of the ignition wire loop.
The ignition wire ignites the sheet and this in turn ignites the
powder charge.
The energy input from the igniter sheets must be taken
into account as extraneous energy during calibration and
testing (see the instructions for the BA 2000).
Performing combustions
All tasks described in this section may be performed
only by knowledgeable professionals.
For the procedure used to coat the decomposition vessel with a
combustion or explosive sample and for the general procedure
used in performing a combustion, we refer you to the applicable
standards/ technical laboratory requirements as well as the
Operating instructions of the IKA C 2000 basic/ control calorimeter
system equipped with the C60 conversion kit.
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Excerpt from the technical delivery requirements TL 1376-600
Part 520:
6 Test requirements
The device (calorimeter) should be adjusted paying close attention
to the Operating instructions.
In contrast to the requirements in the Standards DIN 51900 and
ISO 1928, in this case the heat of explosion is determined at a
loading density of 0.1 g/ml, corresponding to 2.5 g of material
weighed in a bomb with 25 ml. The combustion takes place under
the normal atmospheric pressure of ambient air. The weighing in
process must be accurate to within 0.0001 g. Igniter sheets, which
has a known heat of explosion, is used for ignition.
1 to 2 igniter sheets should be used
and attached to the ignition wire in
a suitable manner. After you have
weighed the sample material into
the crucible, place the crucible in the
decomposition vessel. Screw the cover
with the prepared ignition wire closed
until it is finger tight and then close it
tightly with the mandrel. Do not use any
other tool, since the pretensioning force
that can be achieved with the mandrel
is sufficient!
Check the discharge valve to make certain it is
seated properly!
Check the lower discharge valve before every measurement to
make certain it is seated properly. The discharge valve is selfsealing
and must be raised to release pressure. You can tell that the valve
is seated properly from the position of the valve mandrel (Item
26). When the valve is properly closed, the mandrel must not be
positioned within the valve screw. The valve mandrel sits raised
(0.5 to 1 mm) or, for reasons of
tolerance, flush. Become familiar
with this condition and you will
be able to "feel" when the parts
are in the correct positions!
Transfer the necessary sample
data to the calorimeter (see
C 2000 basic/ control Operating
instructions) and suspend the
decomposition vessel into the filling head adapter (IKA C 60) on
the C 2000 basic/ control calorimeter.
Note that the side screwed connection [Item 10] points in
the direction of the centre of the vessel. Otherwise, the
screwed connection could lie on the edge of the vessel
and the cover would then not close!
Start the calorimeter.
Releasing the pressure from the decomposition vessel
Remove the decomposition vessel from the calorimeter after the
measurement is complete and dry it off.
Pressure must be released from the decomposition
vessel while an exhaust is running! Pressure must
not be released from the decomposition vessel
close to the head!
Hold the composition mit der
Verschraubung vessel with the
screw connection (Item 10)
diagonally
away
from
each
other and screw the threaded
ring (Item 1045) included with
delivery on the bottom part of
the decomposition vessel until
you feel significant resistance.
As much as 500 bar of residual
pressure may remain in the
decomposition vessel after the
combustion. This forces the
valve mandrel on the discharge
valve downward and closes the
valve. By turning the threaded
ring about an additional 180
degrees you can press the valve
mandrel upward and thus open the discharge valve. Combustion
gasses emerge through the side threading. Now you can open the
decomposition vessel!
If you are unable to open the valve without a tool, use the mandrels
that are included with delivery (Item 1040) as aids by inserting then
into the side holes of the threaded ring or pressure container.
A decomposition vessel that is under pressure
cannot be opened! You can tell when a decomposition
vessel is not under pressure from the valve mandrel that is
movable against spring force!
If a decomposition vessel cannot be opened with the tool provided
when it is not under pressure, this indicates an overload of the
decomposition vessel or damage to the threading. In this case,
please contact our technical service department and send the
decomposition vessel in to the factory to be checked.
A decomposition vessel that is under pressure must
not be transported!
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