VWR VP 86 Mode D'emploi page 10

English
Spare part/tool
Small screwdriver, blade width 0.5 mm
Pencil
Tab. 6
Information on procedure
 Always replace diaphragm and valve plates/sealings together to maintain the pump performance.
Health hazard due to dangerous substances in the pump!
Depending on the substance transferred, caustic burns or poisoning are possible.
 Wear protective clothing if necessary, e.g. protective gloves.
 Flush pump before replacing the diaphragm and valve plates/sealings (see chapter 8.2.1).
WARNING
Removing pump head
1. Mark the position of head plate (Fig. 4/3), cover (5) and cover
plate (6) by a drawing line with a pencil. This helps to avoid
incorrect assembly later.
2. Undo the 4 screws (4) in the head plate (3) and lift the head plate
together with cover (5) off the pump housing.
3. Mark the position of intermediate plate (Fig. 5/2) and housing (1)
relative to each other by a drawing line with a pencil.
4. Lift intermediate plate (2) off the housing (1).
Change diaphragm
1. Using a small screwdriver, between the housing (1) and the outer
edge of the diaphragm (9), carefully lever the edge of the
diaphragm lightly upwards
2. Grip the diaphragm (9) on opposite sides, unscrew it about two
turns (anti-clockwise).
3. Hold the pump with one hand, so that the head is pointing
downwards. Turn the diaphragm (9) anti-clockwise to unscrew it.
4. Take the diaphragm support (10) and diaphragm spacer(s) (11) off
the threaded portion of the diaphragm (9) and retain them.
5. Check that all parts are free from dirt and clean them if necessary
(see chapter 6. Cleaning).
6. Put the diaphragm support (10) and diaphragm spacer(s) (11), in
that order, on the threaded portion of the new diaphragm (9).
7. Screw the new diaphragm (9) complete with diaphragm support
(10) and diaphragm spacer(s) (11) into the connecting rod
(clockwise) and tighten it by hand.
Changing the valve plates/sealings
1. Remove the valve plates/sealings (Fig. 5/7) from the intermediate
plate (2).
2. Check that the valve seats, the head plate (3) and intermediate
plate (2) are clean. If scratches or distortion are evident on these
parts they should be replaced.
3. Lay the new valve plates/sealings (7) in the recesses in the intermediate plate (2). The valve
plates/sealings for suction and pressure sides are identical, as are upper and lower sides of the valve
plates/sealings.
4. Check that the valve plates/sealings (7) are not deformed by moving them gently sideways in their
recesses.
5. Dispose of the old diaphragm and valve plates/sealings properly.
Refitting pump head
10
Fig. 4: Removing pump head
Fig. 5: Pump head