Bio-Rad BioLogic Signal Import Module (SIM) - Manual (Page 196)

11.3.3 Routine Maintenance of the Workstation Pumps
The Workstation pumps require minimal maintenance to stay in good working condition. The DuoFlow F10
Pump and F40 Pump Maintenance kits include the piston seals, check valves, and O-rings for routine
maintenance of the pumps. Indications that maintenance is required include flow rates that are below the
specified rate, an erratic delivery of liquid, liquid running out of the washout drain during normal operation
(often seen as salt crystal accumulation), and poor gradient performance.
Safety: Make sure that any hazardous material has been flushed from the system, the pumps are
not running, and any residual pressure has been bled from the system. Disconnect the Workstation
power cord. Wear eye protection, gloves, and other protection as appropriate.
1. Replacing a piston seal. (Refer to Figures 11-1 and 11-2.)
Each pump consists of PEEK pump blocks and screws, piston seals, O-rings and check valves.
This procedure will require new piston seals. See Appendix D, Ordering Information.
a. Soak the piston seals in 50% methanol to thoroughly wet them; sonicate in 50% methanol, if
possible.
b. Disconnect all tubing from the pumphead.
c. Using the pumphead disassembly Allen wrench (or any standard 9/64” Allen wrench), remove
the four long screws on the face of the pumphead center block (see Figure 11-1). Pull the
pumphead away from the Workstation.
d. Note that there are two piston assemblies per pumphead (see Figure 11-2). Each piston
assembly consists of a piston, piston guide, and spring. Use a lab tissue to avoid getting
fingerprints or oils onto the piston assembly. Carefully remove each piston assembly from its
piston well in the pumphead assembly and set it aside.
Figure 11-1. Workstation Pump Mechanism Parts
e. Note the piston seal in each piston well. Always replace both seals at the same time.
Using the piston seal removal tool, pry the seal from the piston well. To do this, you insert the tip
of the seal removal tool into the seal and gently pry the seal away. Once a piston seal is
removed, it cannot be reused.
PUMP HEAD
ASSEMBLY
OUTLET BLOCK
CENTER BLOCK
INLET BLOCK
"LONG"
SCREWS
(8-32 X 1.5")
10
NOTE: FOR BOTH "SHORT" AND "LONG" SCREWS
USE PUMPHEAD DISASSEMBLY ALLEN WRENCH
(OR STANDARD 9/64" ALLEN WRENCH)
MAINTENANCE MAINTENANCE AND TROUBLESHOOTING
11-3