Watson-Marlow PD12I - Manual (Page 11)

INSTRUCTION HANDBOOK
PD12I / PD12P
PD12IP IH 1.03 EN Version: 1.03 Page 11 of 20
5.2 Tube size
Tubes must be selected according to the application and volume to be filled.
PD12 can operate with different tube dimensions chosen according to the volume to be
dispensed.
The tubes are designated by their internal diameters (i.d.) in millimetres. This value is always
used as designation for the individual tube, and this is also the value to be entered in function
2 at the MC12 master controller.
PD12 can operate with the filling nozzles, tubing and Y-connectors listed in the table below.
In order to obtain stable and good filling accuracy, the choice of tubing may be made
according to the following guidelines:
Volume
ml
Nozzle
mm i.d.
Tubing
mm i.d.
Y-Connector
i.d.
< 0.50 0.6 0.5 1.2
0.50 – 1.00 1.0 0.8 1.2
1.00 – 1.70 1.0 1.2 1.8
1.70 – 7.00 1.6 1.6 1.8
7.00 – 12.0 3.2 3.2 3.6
12.0 – 22.0 4.5 4.8 4.8
22.0 – 35.0 6.0 6.0 4.8
>35.0 ml 8.0* 8.0 7.5
Fig. 5.2
* Use non-return valve
Above mentioned tubes are silicone tubes and supplied by Watson-Marlow Flexicon A/S.
These can be sterilised by autoclaving, gamma radiation or ethylene oxide.
It is recommendable that the tubes are of such length that can allow placing the vessel close
to the pump head.
The tube ends must always be kept below the liquid level of the suction vessel in order to
keep the tubes from sucking air.
Avoid having tubes close to the bottom of product vessel.