HARBEN CENTURY, Service Manual

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Flowplant Century Pump Manual
2.3 INLET WATER
2.3.1 General
It is recommended that inlet water is filtered to 50 microns. Filtration to 150 microns is
also possible. Refer to Flowplant Group for advice. Flowplant offer types of filter suitable
for most applications.
Turbulent water will cause the pump to run unevenly and cause excessive wear due to
cavitation. For this reason, water must first pass through a break water or header tank
controlled by a ball valve or float device. Water leaving the tank should have lamina flow
characteristics and be air free.
Notes:
1) If water is filtered before the tank, then the tank must be sealed and vented to avoid
contamination.
2) A pressure/flow check at the inlet to the pump is recommended. The maximum
inlet water pressure for the pump is 0.5 bar (5.0 metre head) and the minimum
recommended 0.05 bar (0.5 metre head).
3) Maximum recommended inlet water velocity 0.5 metres / second.
4) Recommended vortex stopper in tank outlet / pump inlet.
5) Flowplant recommend return line to be on opposite side of tank to tank outlet /
pump inlet.
6) Flowplant recommend that tank should be of sufficient size so that at full flow,
cannot be drained in under 4 minutes.
A pH value of 5 to 9 is recommended. Although liquids outside this range may
occasionally be pumped, it is advisable to contact Flowplant Group, at the address given
in Section 1, for their advice.
Hose and pipe bores between the break water tank and pump should be a minimum of 50
mm (2 in) and up to a length of 1 metre. If a longer length of hose/pipe is required, refer to
Flowplant.
Other points to be considered concerning inlet water are:
(a) Avoid long hose or pipe runs.
(b) Avoid hose or pipe runs that cause air pockets.
(c) Refer to circuit layout for mounting angle of pump.
(d) If water inlet temperature is over 30°C, consult Flowplant.
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