Flow rates – Watson-Marlow 505Dz User Manual

Page 6

For higher accuracy, use smaller bore tubing. However this will also increase
filling time.

For faster filling time increase tubing bore size. However this will decrease
accuracy.

All tubing will show a gradual drift in the dosed volume, which can be corrected
by recalibration. For minimal drift use Silicone tubing (if chemically compatible).

The results seen on page 6 were obtained using Silicone tubing pumping water
at zero suction and delivery pressure, with a 501RL pumphead at 300rpm over
at least 50 doses. It is intended as a guide only.

It is advised to carry out trials under operating conditions to determine a
satisfactory compromise between dose time and accuracy. The important
factors are suction and delivery pressures, temperature, and fluid viscosity.

Flow rates

The 505Dz is fitted with the 501RL pumphead. The flow rates given below were
obtained using silicone tubing, with the pumphead rotating clockwise, pumping
water at 20C with zero suction and delivery pressures (unless otherwise stated).
Where an application is critical, the flow rate should be determined under
operating conditions. The important factors affecting flow rates are delivery
pressures, temperature, and fluid viscosity. Tube life will be reduced when
pumping against pressure.

501RL flow rates (ml/min)

Tube #

112

Tube bore

0.5mm

0.8mm

1.6mm

3.2mm

4.8mm

6.4mm

8.0mm

1/50"

1/32"

1/16"

1/8"

3/16"

1/4"

5/16"

300 rpm

12.5

128

560

1210

1900

3000

Note: 501RL pumpheads must not be run at speeds greater than 300rpm