Check Valves - Knauer WellChrom HPLC Pump K-1001 Handbuch

Easy Maintenance
SOP 28 Installing the pump head

Check valves

SOP 29 Replacing check valves
3. With the open side facing downwards press the new piston seals {3.11}
carefully into the ceramic seal holder, making sure to keep it straight.
4. Lock the ceramic seal holder in place by attaching the check valves {3.10
and distance holder {3.10a} according to SOP 30 "Cleaning check
valves" on page 36.
5. Place the O-rings {3.21} in the inner side of the pressure plate {3.13}.
6. Install the pressure plate, item {3.13}. Take care on the orientation of
housing and pressure plate. Using the SW 5/16 spanner, tighten the
spacing bolts, {3.14} firmly.
7. With the open side facing downwards carefully press the new piston
seals {3.11a} into the spaces of the pressure plate, making sure to keep it
straight.
8. Cover the seals with the pressure discs {3.20}.
9. Install the two guides for spring, {3.16} and the springs, {3.15}.
10. Install the retaining plate, {3.18}.
11. Insert and tighten the two screws {3.19} strictly alternating due to strong
force of the springs, {3.15} behind the plate.
12. Insert the piston rods {3.17} carefully without bending or quenching the
rods.
13. The spacing bolts, item {3.14 and the retaining plate screws, item {3.19}
must be tightened that they are seated as securely as before.
1. Make sure that the pump head is properly assembled, especially check
step 13 of the SOP 27.
2. Position the head in a straight line onto the pump housing.
3. Tighten all four pump head set screws, item {3.3} a few turns by hand.
4. Alternating from one to the next, tighten two diagonally opposed screws
half a turn at a time, until the pump head is correctly seated.
5. Tighten the two remaining screws. Make sure that all four pump head set
screws, item {3.13} are securely tightened.
6. Mount the capillary connection between the pump head outlet and the
pressure transducer.
7. Connect the solvent tubings according to SOP 19 on page 26.
If check valves are contaminated they will no longer open and close correctly.
You can remove the check valves for cleaning purposes from the pump head.
Disassemble them according to the following instructions.
Remove the connection to the solvent reservoir.
1. Remove the bushing on the inlet side {3.5} The lower check valve {3.10}
can now be removed together with the bushing.
2. Remove the complete capillary connection {3.22} between the two pump
chambers. Loosen the screw fittings alternating, to avoid bending the
capillary.
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