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DESMI Pumping Technology A/S
10
Tagholm 1
9400 Nørresundby - Denmark
Tel.: +45 96 32 81 11
Fax +45 98 17 54 99
E-mail:
ATTENTION
For safety reasons the pump is only allowed to operate against closed discharge valve for a short
time (max. 5 minutes and at a max. temperature of 80°C for standard pumps). Otherwise there is a
risk of damage to the pump and, at worst, of a steam explosion. If the pump is not monitored, the
installation of a safety device is recommended.
9.1
START-UP
Before starting the pump check that:
- the shaft rotates freely without jarring sounds.
- the pump casing and the suction line are filled with liquid.
Start the pump for a moment to check the direction of rotation. If the direction is correct (i.e. in the
direction of the arrow) the pump may be started.
10.
SYSTEM
BALANCING
It is often difficult to calculate a manometric delivery head in advance. It is, however, decisively
important to the quantity of liquid delivered.
A considerably smaller delivery head than expected will increase the quantity of liquid delivered,
causing increased power consumption and perhaps cavitation in pump and piping. In the pump the
impeller may show signs of heavy erosion caused by cavitation (corrosion) which may at times
render an impeller unfit for use in a very short time. Not unusually do similar erosions occur in pipe
bends and valves elsewhere in the piping system.
Therefore, after start-up, it is necessary to check either the quantity of liquid delivered or the power
consumption of the pump e.g. by measuring the current intensity of the connected motor. Together
with a reading of the differential pressure the quantity of water delivered can be determined against
the characteristics of the pump.
Should the pump not function as intended, please proceed according to the fault-finding list. Bear
in mind, though, that the pump was carefully checked and tested at the factory and that the
majority of faults stem from the piping system .
Summary of Contents for NSLH Compact Spacer
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