Wilo NPG 100-315, Installation And Operating Instructions Manual

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English
Installation and maintenance instructions Wilo-Horizontal pumps NP
G
4.4 Piping
4.4.1 Suction and discharge pipework
The dimensions of the pipes do not directly
depend on suction and discharge diameters of the
pump.
a) First, choose a flow speed < 2 m/s at suction,
and about 3 m/s at discharge.
b) Take into account the available NPSH, which
must be superior to the required NPSH of the
pump.
Never use pump as a support for piping. Do not
mount expansion joints in such a way that their
force, due to internal pressure, may act on the
pump flange.
Maximum forces and moments allowed on the
pump flanges vary with the pump size and type.
These external strains may cause misalignment,
hot bearings, worn couplings, vibrations and the
possible failure of the pump casing.
When designing the pipes (§ 4.4.2.1, § 4.4.2.2,
§ 4.4.3.1) take necessary precautions in order not
to exceed maximum allowed strains.
Forces and moments applied to the pump flanges
must never exceed the values shown in the table
below:
Forces and moments values are applied to the
whole flanges and not flange-by-flange. For their
sharing out on the pump flanges, refer to standard
NFCR 13 931.
4.4.2 Suction piping
4.4.2.1 Design of a flooded suction line
The suction line must be as short and direct as
possible, never mount an elbow directly on the
Protective covers are fitted to the pipe
connections to prevent foreign bodies
entering during transportation and
installation. Ensure that these covers are
removed from the pump before connec-
ting any pipes.
CAUTION!
DN
Flange
Forces (daN) Moments (m.daN)
Fy Fz Fx
¦
F My Mz Mx
¦
M
Vertical Discharge 150 160 200 180 310 45 60 80 110
200 215 265 240 415 85 100 125 180
250 270 335 300 520 125 145 180 260
300 320 400 360 625 170 200 240 355
350 375 465 420 730 220 255 310 455
400 430 530 480 835 275 320 390 570
450 485 600 540 940 340 390 480 705
500 540 665 600 1040 410 470 580 850
Horizontal Suction 150 180 160 200 315 45 60 80 110
200 240 215 265 415 85 100 125 180
250 300 270 335 520 125 145 180 260
300 360 320 400 625 170 200 240 355
350 420 375 465 730 220 255 310 455
400 480 430 530 835 275 320 390 570
450 540 485 600 940 340 390 480 705
500 600 540 665 1040 410 470 580 850
Ensure piping and fittings are flushed
before use.
CAUTION!
Ensure piping for hazardous liquids is
arranged to allow pump flushing before
removal of the pump.
CAUTION!