Buchi K-437, Operation Manual

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7 Maintenance and repairs
24
K-437 Operation Manual, Version A
7 .3 Digestion tubes
ATTENTION
Do not use cold water to cool down hot digestion tubes after digestion. The resulting temperature
shock might lead to tensions in the glass.
incorrect correct
Use the optional retaining plate to wash the digestion tubes
together with the sample rack in the laboratory washing instru-
ment. Thus the tubes will not be damaged during washing.
To clean the tubes, proceed as follows:
Mount the retaining plate onto the rack at the points provided. •
Put the retaining plate with the rack into the laboratory washing •
instrument with the tube openings pointing downwards.
Remove the retaining plate after washing. The digestion tubes
•
are now clean and ready for the next analysis.
7 .4 Sealing system
ATTENTION
When removing and reinstalling the seals and gaskets, make sure not to damage them. Always move
them perpendicularly to the axis of the glass parts and ensure no damage occurs to the sealing lip.
Never apply grease to the seals and never touch them with sharp objects, otherwise they will get
damaged.
7 .4 .1 Cleaning the seals
To prolong the lifetime of the seals, rinse them regularly with water, especially if working with crystalline
products. Afterwards, dry them with a soft cloth.
7 .4 .2 Replacing the seals
Seals are subject to wear and tear, thus you should check them regularly and replace them, if neces-
sary.
7 .5 Exhaust unit
The exhaust unit can be cleaned under running water or in the laboratory washing instrument.