Knauer WellChrom HPLC Pump K-1001 Handbuch Seite 33

Easy Maintenance
SOP 25 Removing and Checking Piston Rods
SOP 26
4. Remove the „Connection capillary", Pos. {3.8},.
5. Loosen the „Inlet valve housing", Pos. {3.5} as well as the fittings at
„Outlet valve housing", Pos. {3.6}.
6. Using a hexagonal spanner no. 4 (4 mm), loosen just two diagonally
opposed „Head set screws", Pos. {3.3}. Remove the screws, see Fig. 26.
7. Carefully loosen the two remaining screws, alternating from one to the
other, approx. half a turn. This prevents the pump head from tilting and
becoming damaged. Once the spring tension has been reduced, hold the
pump head firmly in one hand while removing the screws completely with
the other hand.
8. Carefully remove the pump head.
This SOP refers as well to the 10 ml as to the 50 ml pump heads:
1. Remove Pump head as described in SOP „Removing the Pump Head".
If you only wish to check the piston rods, you do not need to disassemble the
pump head any further.
2. The „Piston rods", Pos. {3.17} in Fig. 26, may be removed using pliers.
Take the tip of the piston using the pliers, and pull it out carefully in a
straight line.
If the rods are broken, you must check the entire pump head for damage.
Disassembling the pump head
All position numbers of the components are related to Fig. 26.
1. Apply SOP 25 "Removing and checking piston rods".
2. Loosen the two retaining plate screws, Pos. {3.19} half a turn, alternating
from one to the other to avoid damaging the Retaining plate. Because the
two screws are very tight, it may be helpful to either clamp the pump
head or to press one of its side surfaces against a table with one hand
while loosening the screws.
3. Unscrew the two screws strictly alternating due to strong force of the
springs, Pos. {3.15} behind the plate, and remove them.
4. Remove the retaining plate, Pos. {3.18}
5. Remove the spring guides, {3.16} and the springs{3.15}.
6. Use a SW 5/16 spanner to loosen the spacing bolts, {3.14}. These bolts
are seated very tightly. Follow the advice given in step 3.
7. Remove the pressure plate, {3.13}.
8. Remove the pressure discs {3.20} out of the pressure plate {3.13}.
9. To remove the piston seals {3.11a}, the easiest way is to pull them out
using a 4mm gimlet or a screw of corresponding diameter.
10. The piston seals {3.11} located in the ceramic seal holder {3.12} are to
remove in the same manner.
11. To remove the ceramic seal holders from the housing (not necessary for
exchanging the seals) please follow SOP 30 "Cleaning check valves" on
page 36 to remove as well the check valves {3.10} as the distance
holders {3.10a}.
12. The ceramic seal holders {3.12} can be removed from the housing {3.4}.
33