Function and setup of the PlasmaQuant PQ 9000
PlasmaQuant PQ 9000
Edition 05/2014
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Figure 4
Concentric nebulizer and spray chamber
Torch
The torch has a three-shell construction and comprises an outer tube, an inner tube and the
inner injector tube.
The outer tube, in conjunction with the bonnet inserted into the coil, electrically insulates the
plasma from the induction coil and shields the plasma from the ambient air. The plasma gas
flows between the outer and inner tube. This gas is ionized at the induction coil and converted
to a plasma state. The tangential flow of the plasma gas into the space between the outer and
inner tube cools the outer tube and prevents it from melting due to the high plasma
temperatures.
The auxiliary gas flows in the intermediate space between the inner tube and the injector. It
pushes the aerosol of the sample solution away from the injector.
The injector has the task of injecting the sample aerosol into the plasma. The measurement
solution is transported by the nebulizer gas from the spray chamber through the injector into the
plasma.
Figure 5
Schematic structure of the torch with gas flows
The torch is available as a demountable version in individual parts (demountable torch) or as a
single unit (one-piece torch). The demountable version offers the possibility of replacing worn
individual parts, such as the outer tube, which are subjected to extreme thermal loads. During
assembly, however, care must be taken to ensure the individual parts are inserted gas-tight into
one another and especially to check that the injector is seated correctly. The cost of purchasing
a one-piece torch is slightly lower. It is cleaned as a whole, making disassembly and
