VWR International VWR 10, Instruction Manual

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Removing the piston
1/ Remove the tip-ejector and (optionally) the lower part of the tip-holder.
If you remove the lower part, take care to remove the O-ring as described
in “Changing the O-ring”.
2) Unscrew the connecting nut (turn by hand, counterclockwise).
3) Gently remove the connecting nut and upper tip
holder.
4) Pull off the piston assembly from the body of the
pipette
– separate the parts (see opposite).
5) Clean and autoclave (if required) the piston and
holder, together with any other parts that may need
to be treated in the same way.
In the case of 1200µl pipette, the piston holder,
piston and
guide are a unit. Don’t try to separate them!
6) Lubricate the piston, see below.
7) Reassemble the piston and guide; then carefully insert the assembly into the body of the pipette.
The guide should hold the piston assembly inside the body of the pipette. You can hear a “click”
when the piston is back in place.
Take care not to touch the piston, and that it is dust-free. If needed, clean the assembly with a
dust-free cloth.
8) Reassemble the upper part of the tip-holder and the connecting nut, and then refit to the body of
the pipette by rotating the connecting nut clockwise until it is finger tight. Fit the O-ring (for VWR10,
the seal) and reassemble the lower part of the tip-holder. Refit the tip-ejector. The seals for VWR10
are fragile and can be used only once. So, after unscrewing the lower part of the tip-holder you
must fit a new seal.
The specification of the pipette
must be checked after changing
any part!
Don’t pull on the piston to remove
the assembly!