Wilo Wilo-Drain SP, Инструкция по установке и эксплуатации

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ENGLISH
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
Open slightly the discharge valve (only if no auxiliary venting pipe is
installed).

Open all valves in suction line.

Switch on the pump

Wait until pump has primed and note this priming time. Then close
the discharge isolating valve and measure max pressure (zero flow).
Compare this pressure to the shutoff pressure available on the hydraulic
curve.
In order to avoid overheating of the liquid inside the pump the
pump should not work more than 20 to 30 seconds against a closed
discharge valve.

If expected pressure is reached then open progressively the discharge
valve.
8.4 RUNNING CHECKS
During operation of pump in duty conditions (capacity, head,
temperature, …) the following points must be checked :

Check and note pump duty point. If necessary convert pressure value
from bar indicated on the pressure gauge to mwc :
HMT
mce
= (P
bar
x 100) / (SG x 9,806) with SG= fluid Specific Gravity.

Check and note current consumption on each phase of the motor.

Check calibration of motor protections.

Check temperature of ball bearings (on bearing housing surface).

Check flexible coupling alignment after several pump starts (only for
concerned pumps variants).

Check tightening of flanges fastening bolts.

Check there is no leakage and no abnormal running noise.
When pumping hot fluids, the definitive coupling alignment should
be done only when system nominal temperature is reached and
stabilized. See chapter 7.1.4 COUPLING ALIGNMENT
Check the surface temperature on the bearing bracket and on the
pump casing. Check pumped fluid temperature. Alarm and stop
trips settings should be done according those values. Refer to specific
sensors IOM before adjusting those trips.
8.5 SHUTDOWN
Before the pump is stopped close the discharge isolating valve.
Ensure that the pump runs in that condition no more than few
seconds.
When the pump has come to a standstill : close the suction isolating
valve. If the pump is equipped with auxiliary systems such as a quench,
heating system, flushing, external lubrication, etc … it must be closed at
the last step.
If temperature is likely to drop below freezing point, pump casing
and auxiliary connected systems should be completely drained or
otherwise protected. For prolonged shut-downs an adapted rust
protective coating should be applied to the inside and outside of the
pump.
Pumping explosive, toxic or polluting fluids : make sure that all
necessary actions were taken to avoid the creation of a hazard for
people or environment during drainage operations.
Products which are sent back to WILO must be drained and
cleaned. Pumped fluid should be completely removed from the
pump.
8.6 PRIMING TIME
The suction line drains down into the tank between two starts. The flow
does not appear immediately after pump start but only after a few
seconds : it is called priming time.
Piping will be design in order to allow free air extraction without
counter-pressure (discharge back to tank, vent valve, discharge line
to an atmospheric exhaust …).
Even if the mechanical seal is equipped with a quench behind the
stationary seat, priming time will be limited to 5 minutes. If
discharge pressure doesn’t rise after this time, stop the pump and check
piping system.
For an ATEX application, it may happen that the alarm temperature
is reached before pump has primed. Measure liquid temperature
and modify alarm and stop trips settings accordingly.
Theoritically the pump could prime up to 8 meters but lifting
height will be limited to 6 meters to take suction line head losses
into account.
Check that the system available NPSH (NPSH
A
) is always higher
than the required NPSH (NPSH
R
) of pump when fluid level is at its
lower point.
Theoretical priming times (Nominal Dia of pipe = pump nominal dia) :
Pump size Pump speed
Priming time in seconds vs
suction lift height. [Tt]
2 3 4 5 6
40 2900 21 47 78 135
41 2900 27 57 93 153
45 2900 12 22 35 47 62
46 2900 5 8 13 23 34
50 2900 17 29 46 83
51 2900 19 34 55 87 155
60 2900 19 29 42 56 77
61 2900 10 15 21 29 41
63 2900 7 10 14 19 33
65 1450 30 58 83 186
68 2900 9 14 19 26 38
80(-2) 2900 36 49 62 74 95
80 2900 21 53 95 132
83 2900 14 20 26 31 39
85 1450 32 63 100 152
88 2900 4 7 11 18 26
88 (210) 2900 5 8 11 15 20
100 2900 19 30 38 45 54
105 1450 38 69 110 167
105 2300 9 13 17 21 25
105 T114 1450 30 62 110 189
108 2900 10 14 18 22 27
120 1450 10 18 31 50 95
If there is no liquid delivered or if discharge pressure is too low
then see chapter “trouble shooting”.