Watson-Marlow 120F/DV - Manual (Page 21)

Watson-Marlow 114DV pumphead: operating instructions 3
3.3 114DV pumping
conditions: pressure
and viscosity
All pressure values in this operating instruction,
from which performance life figures have been
calculated, relate to root mean square (RMS)
pressure, giving a more relevant pressure value
than figures quoted in terms of peak pressure.
The RMS pressure is similar to the value you
would read on a damped analogue gauge.
Ensure that there is always a minimum of one
metre of flexible tubing connected to the
discharge side of the pumphead. This helps to
minimise any impulse losses and pulsation in
the pipeline. This is especially important with
viscous fluids and rigid pipework.
3.4 114DV pumphead
installation
A correctly engineered installation will promote the
best possible tube life, so please ensure that the
following guidelines are followed:
Avoid tight pipeline bends, pipe reducers and
excessive lengths of smaller bore tubing than
that in the pumphead, particularly in pipelines
on the suction side.
Ensure that connecting pipework and fittings
are suitably rated to handle the predicted
pipeline pressure.
If rigid pipework comes in close proximity to
the pumphead, a drop-out section of pipework
will simplify tube replacement.