The standard Accuramatic dispenser operates with 2mm wall tubing (these pumps have red rotors, or black on some older models). Since some tubing types are only available in 1.6mm wall thickness, we have developed an alternative rotor (silver anodised aluminium) for applications always requiring such tubing. Correct thickness of tubing wall is crucial to pump operation.
| Tubing bore size | Delivery rate (ml/sec) | Recommended for doses |
|---|---|---|
| 1mm (twin) | 1 (per tube) | Up to 5ml |
| 2.4 | 4 | 5-15ml |
| 4 | 10 | 15-50ml |
| 6 | 24 | 50-125ml |
| 8 | 36 | Over 125ml |
MECHANICAL CONSIDERATIONS IN TUBING USE
SUCTION
Peristaltic pumps operate through the suction created by the
flattened tubing regaining its shape. If the tubing does not recover fully
before the next roller pass, the flow is diminished. There are several possible
causes:
Excess head: it is not advisable to pump from a reservoir
more than 1m below the level of the pump.
High viscosity product: a
product at 100cP pumps 60% as efficiently as water. Keep the tubing on the
suction side short. Try using a larger bore than that running through the
pump.
Over-long suction tubing: if using a long suction tube, try a
larger bore size (2mm on diameter) than the delivery side, with a tube connector
near the pump.
Tight bends: these restrict flow through the tubing.
Wall suction: occurs where the suction end of the tubing sucks onto the wall
of the reservoir,
causing a massive drop in pump output and a flapping noise from the pump head
where the tubing is staying flat. Rectify by cutting a V notch in tubing or
using a sinker with a ridged base.
TUBING AGE
Tubing doesn’t last forever! Extend tubing life by
moving it along so the pump wear is spread over different sections. Dose
accuracy actually improves a little during the first hour of a tube’s use, and
deteriorates spectacularly just before tubing splits at the end of its life, as
the material structure starts to break down.