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PLC 2050/2250/2500 PurifiCation SyStemS
| uSer’S GuiDe
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5. Loosen the four m4 screws (counter-clockwise) of the
head in an alternating criss-cross pattern with a 3 mm
allen wrench.
6. Hold the pump head and consecutively pull out the
four screws.
7. Carefully remove the pump head. the piston and the
cleaning disc (PeeK part) will be visible.
8. Carefully remove the cleaning disc to fully expose the
piston.
NOTE
If needed, disconnect the ETFE junction tubing for
cleaning discs by hand (PEEK nuts under pump
head).
Cleaning Discs
Cleaning Disc
Figure 58
removing the Pump Heads
exposed Pistons
exposed
Piston
Figure 59
removing the Cleaning Discs
Replace a Pump Seal
NOTICE
the life of the seals is dependent on the flow rate, pressure, type of liquids used and
temperature used in the machine, but mostly on the cleanliness of the mobile phase and
sample. the presence of micro-particles will cause accelerated wear and tear of the seals.
Similarly, any dried buffer particles on the piston will damage the seal.
When disassembling or reassembling the pump, make sure that each component is clean and
take care that the system is assembled in a clean environment.
there are four seals: one for each pump head, and one for each cleaning disc.
to disassemble a pump head with cleaning disc, and to replace a seal, follow the instructions
below:
Remove the Pump Head and the Cleaning Disc
1. Purge the system with a suitable solvent.
2. Switch off the system and disconnect it from the mains. (refer to
3. Disconnect the etfe inlet tubing by hand (PeeK nut).
4. Disconnect the SS outlet tubing with a 3/8” spanner (SS nut). When loosening the SS nut,
use a 17 mm spanner to hold the check valve housing. you have to remove the tubing (i.e.,
disconnect it from the purge valve holder).
etfe inlet tubing with PeeK nuts
(Below Check Valve Housings)
SS outlet
tubing
Check Valve
Housings
Figure 56
removing the outlet and inlet tubing
m4 Screws
Figure 57
Loosening and removing m4 Screws
