Pump Head And Pistons - Thermo Scientific Dionex UltiMate 3000 Series Operating Instructions Manual

UltiMate 3000 Series:
LPG-3400XRS Pump

7.3.2 Pump Head and Pistons

Tip: When performing service procedures for the pistons and the piston seals,
remove the pistons from the seals as little as possible to preserve the quality of
the seals.
7.3.2.1 Removing and Disassembling the Pump Head
To remove the pump head from the interior front panel
1. Tilt the front cover upward.
2. If necessary, purge the pump to remove toxic solvents.
3. Turn off the main power switch and disconnect the power cord.
4. Remove the four bayonet-type proportioning valve connectors on the left side of the
pump head. As a help, you can use the tool for the bayonet-type connectors from the
accessories kit for the pump (part no. 6043.0061).
5. Put on a pair of clean room gloves to prevent contamination on the valve parts. Even
minute particles may cause damage to the system and result in poor pump
performance.
6. Disconnect all fluid connections from the pump head (solvent lines, rear seal wash
tubing, capillaries on the outlet).
7. Two clamping screws fix the piston drive unit cover on the right side (→ Fig. 43).
Loosen the two screws using a ball-head screwdriver (size 4 mm, included in the
accessories kit of the pump). Thus, you loosen the springs which hold the pistons in
the piston drive unit.
Be sure to open the clamping screws enough to avoid damage to the pistons.
Fig. 43: Loosening the clamping screws on the drive unit cover
Page 110 Operating Instructions