D-Series Syringe Pumps - Isco

D Series Syringe Pumps
Section 5 Pump Maintenance & Repair
5.3 Seal Cleaning and
Replacement
Before cleaning or replacing the piston or wiper seals, the cylinder
must first be emptied. To access the cylinder:
1. Run the pump at maximum flow rate until it’s empty.
2. Disconnect the power cord.
3. Disconnect the pump pressure transducer cable from the
controller and remove the tubing from the inlet and outlet
ports.
4. Remove the front cover of the pump.
5. Loosen the four cover screws.
6. Then loosen the cylinder lock screw which is a 1 4-20 setscrew
located in the front side of the cylinder mounting
block.
7. You may now unscrew the cylinder. If you need to use a
wrench, we recommend using a strap wrench or the
wrenches in the Teledyne Isco wrench package
(60-1247-067 for 65DM, 100DM, 100DX, and 260D;
68-1247-068 for 500D;
60-1247-093 for 1000D), which will not mar the cylinder’s
outer surface.
8. Once the cylinder has been unscrewed, lift it up and off the
piston and the push tube.
5.3.1 The Piston Seal Sometimes dirt or other solids on the seal can cause leakage.
Removing and cleaning the seal may stop the leak and a new seal
may not have to be used. However, if you remove and inspect the
seal and it does not have any obvious crease or you did not find
any foreign material on the seal, then the seal must be replaced.
Check the wear ring. See Section 5.4.
Note
DO NOT use abrasives while cleaning the piston and piston
seal area. Scratches caused by the use of such abrasives will
cause leaking. If either the cylinder or seal has been
scratched, it must be replaced to maintain flow rate specifications.
Note
If your pump uses polyethylene piston seals, be sure to follow
the special instruction below for this type of seal.
Accessing the Piston Seal
1. Unscrew the piston seal retainer (Figure 5-2) from the piston
and remove the seal from it. Notice that the spring
imbedded in the seal is facing up or is on the top side of the
seal.
2. Clean both the piston seal retainer and the cylinder thoroughly.
Make sure all parts that come into contact with the
seal are free of dirt and other solids.
5-5