Figure 4-5 Vaporization Temperature - Siemens Maxum II PD PA AP Service Manual

Valves
4.2 Liquid Injection Valve
Vaporization Temperature
The vaporization temperature can be set independently of the oven temperature. It is selected
according to the sample and the boiling point of the sample. The optimum vaporization
temperature must be determined experimentally. The amount by which the vaporization
temperature should be above the sample's boiling point depends on the heat of vaporization
of the sample. Samples with a high heat of vaporization, such as aqueous samples, only
vaporize sufficiently fast for chromatographic purposes at high temperatures (above 200°C),
as shown below.
Figure 4-5
Note
Ex units: To comply with electrical hazardous area requirements ensure that:
● The sensor of the temperature sensor is fully inserted into the heating plate.
● The purge tube vent is not being obstructed.
Filter Requirements
The tappet and gaskets will wear faster if the sample contains solid particles. In these cases,
a filter is required upstream of the injection. Siemens recommends a filter with the following
characteristics:
● 98% for 0.3-μm particles with liquid samples
● 99.99% for 0.1-μm particles with gaseous samples
36
Vaporization Temperature
Maxum II Valves and Oven Components
Service Manual, 10/2018, A5E42019844001