ELTRA CS-2000, Руководство пользователя

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Analysis
26
5.1.2 Induction furnace
The steel analysis is described in the following section, as an example.
Ensure that the compressed air and oxygen supply are turned on. They should normally not be
turned off anyway during working hours. By turning the mains switch to position 3, the heating
for the generator tube and the cooling blower are switched on, as well as a valve which allows
the oxygen to flow through the analyzer. It is advisable to let the oxygen flow through the
analyzer for several minutes before beginning of analysis after a break, so that the temperature
inside the analyzer is stabilized. During brief work breaks, therefore, the oxygen is not turned off
and the mains switch is left on position 3.
Make sure that the chemicals are in proper condition. See chapter
”Reagent tubes filling”
.
A crucible is placed on the balance and tared by pressing the ”TARE” key. 1.5 g tungsten are
put into the crucible. Tare the balance again. Put the sample into the crucible. A weight of about
500 mg steel or cast iron is usual. Then the weight is transferred to the PC and can be seen on
the screen.
Remark
The crucible must only be picked up with clean crucible tongs and never be handled with
fingers!
Remark
Only the sample weight should be transferred to the PC; on no account the weight of the
accelerator.
For all instructions on operating the PC software refer to the Help-function of the software.
The crucible is placed on the pedestal and the analysis is started (F5). The furnace closes.
“ANALYSIS” appears in the “status” window of the software, indicating that the analysis cycle is
running. The analysis now runs by itself, so that nothing more needs to be done manually. The
signals from the infrared cells are monitored on the “graphics” window of the software. At the
end of analysis the results are shown on the screen.
When an IR range cell is saturated, it is automatically deactivated. In case of two cells for one
element, if the low range is saturated, the analyzer changes automatically over to the high
range. If high ranges are saturated, a row of asterisks appears on the screen. When the next
analysis is started, any overloaded ranges are automatically reactivated.
Remark
The mains switch should not be changed from position 3
while “ANALYSIS” is shown in the
status window. If, however, the analysis is mistakenly started while the mains switch is on
position 1, the analysis should be interrupted with the
“Abort” button. The sample weight must
be re-entered, and then the analysis is restarted.
Remark
Note the sample weight before pressing “Abort”, because the sample weight must be entered
again manually before starting an analysis after “Abort”. The first analysis after switching from
position 1 to position 2 (or 3) should be carried out after about 10 minutes, because the oxygen
supply is thereby switched on, purging air and moisture out of the gas flow system.