Metrohm 874 USB Oven Sample Processor - Manual (Page 22)

3.4 Mounting the needles ￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭
14 ￭￭￭￭￭￭￭￭ 874 Oven Sample Processor
Note
If vessels with other dimensions are to be used, then individually modi-
fied sample inserts can be ordered. The precise vessel dimensions
(including tolerances) will be required when ordering. Non-standard
sample vessels may not exhibit dimensions outside of the following limit
values:
￭ Diameter 10.0…32.0 mm
￭ Immersion depth 20.0…45.0 mm
3.4 Mounting the needles
Two different types of needle holders are available for mounting needles.
The length of the needle holder defines how deeply the injection needle
penetrates the sample vessel. The 6.2049.040 needle holder, which is
58 mm in length, ensures that the needle penetrates the liquid or pow-
dery sample. The carrier gas can flow through the sample and effect an
efficient expulsion of the moisture it contains.
If there is a danger that the heated sample could clog the needle, then
use the 6.2049.050 needle holder with 73 mm length. In this case the
injection needle penetrates the sample vessel only slightly deeper than the
outlet needle and has no contact with the sample itself.
Needle holders with the dimensions required for situations calling for spe-
cial sample vessels can be supplied by Metrohm upon request.