Metrohm 881 Compact IC pro – Cation - Manual (Page 64)

5.5 High pressure pump
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881 Compact IC pro – Cation
￭ Remove the backup ring from the pump head and lay to the other
parts.
1 2 3 4 5 6 7 8
Figure 24 Components of the piston cartridge
1 Piston cartridge screw 2 Retaining washer
3 Zirconium oxide piston with piston
shaft
Order number: 6.2824.070 4 Spring retainer
5 Spring
Order number: 6.2824.060 6 Inner plastic sleeve
Protects from metallic abrasion.
7 Piston cartridge 8 Backup ring
3 Cleaning the components of the piston
￭ Clean zirconium oxide pistons contaminated by abrasion or
deposits with fine abrasive cleaning powder, rinse particle free
with ultrapure water and dry.
Replace highly contaminated or scratched zirconium oxide pistons
(spare part: 6.2824.070 zirconium oxide piston).
￭ Rinse the other parts of the piston and dry with a lint-free cloth.
4 Assembling the piston
￭ Insert the inner plastic sleeve, spring and spring retainer into the
piston cartridge.
￭ Slide the zirconium oxide piston carefully into the piston cartridge
until its tip emerges from the small opening of the piston car-
tridge.
￭ Attach screw and tighten by hand.
Replacing the piston seal
The special tool (6.2617.010) (see Figure 25, page 57) is necessary to
remove the piston seal from the pump head. It consists of two parts: a tip