Metrohm 838 Advanced Sample Processor Installation Instructions - Manual (Page 24)

18 838 Advanced Sample Processor, Installation
2 Preparing the filtration membrane
• Remove a new 6.2714.020 filtration membrane 34 from the packag-
ing using the 6.2831.010 tweezers and immerse it for approx. 2 min-
utes in a petri dish filled with ultra-pure water until the membrane is
fully soaked with water.
It is imperative that the filtration membrane be soaked with water be-
fore inserting it into the filtration cell since this causes it to expand. If it
is inserted dry, this will then lead to creasing and folding in the filtration
cell which may result in blockage of the cell.
3 Inserting the filtration membrane
• Place the upper section 29 of the ultrafiltration cell with the inside
pointing upwards on a clean paper towel.
• Insert the sealing ring 30 into the recess provided on the upper sec-
tion.
• Place the wet filtration membrane, using the tweezers, centred inside
the sealing ring, onto the upper section.
4 Closing the ultrafiltration cell
• Fit the upper section onto the lower section 31 so that the two parts
fit perfectly.
• Using the 6.2621.070 Allen key, screw in the 5 screws 32 with wash-
ers fully and then tighten firmly.
5 Fitting the ultrafiltration cell
• After screwing the ultrafiltration cell together, fit it, as shown in Figure
17, in the holder 10 so that the heads of the screws 32 are located
in the holes provided in the holder.
Please use only the specified 6.2744.000 PVDF pressure screws
for connection to the ultrafiltration cell. If you use the 6.2744.010
PEEK pressure screws, this may result in stress cracking on the ultrafil-
tration cell!
6 Rinsing the ultrafiltration cell
• First make the required tubing connections (see section 3.3.11) and
then proceed as follows:
• After fitting a new filtration membrane, it is necessary to remove any
air still in the filtration cell and in the lines. In order to do this, you
should flush all lines with ultra-pure water from one of the special
beakers for instance:
• Position a 300 ml PE bottle containing ultra-pure water as the rins-