salmson NEX, Инструкция по установке и эксплуатации

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ENGLISH
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If a coupling spacer is used the motor won’t have to be moved rearward
during maintenance operation.
Various materials and shaft sealing are available. This pump is designed
to handle aggressive, viscous or turbid fluids. The bearing bracket can be
equipped with reinforced ball bearings for demanding applications.
6.2 FUNCTION
NEX pump is a centrifugal pump with axial inlet and radial outlet.
Depending on required discharge pressure the pump speed is 1450 or
2900 RPM.
An open impeller/reverse vane impeller turns inside the pump casing
(direction of rotation is clockwise seen from drive end). The rotation
movement is transmitted to the fluid that is driven to the vanes and
then pumped to the discharge flange where it leaves the pump. In the
flow passage of the pump casing the kinetic energy of the fluid is
converted into pressure energy.
NEX pumps are not self-priming pumps. Suction line and pump casing
should be completely filled with liquid before pump start.
When necessary or when a maximum pumping efficiency is required
several possibilities are offered to adapt capacity/pressure.
Modification of the system hydraulic characteristics :
A regulating valve is added at the discharge side of the pump. The
hydraulic loss can be adjusted and so the pump duty point.
Modification of pump characteristics :
Use of a frequency inverter gives the possibility to adjust pump speed.
The pump hydraulic curve is modified to reach required duty point but
impeller diameter is unchanged.
7 INSTALLATION AND ELECTRICAL
CONNECTION
7.1 LOCATION
Equipments that will be used in a ATEX zone should be
certified accordingly and should fully comply with applicable
regulations.
The choice of the pump location should permit a proper cooling of the
motor and should respect following limits :
Location will be chosen to ensure space reservation for maintenance
and inspection.
Check that there is ample overhead for lifting and that lifting devices are
available.
7.1.1 FOUNDATION
Pump set can be installed on various types of foundations (on a concrete
ground, on a foundation concrete block, on a steel framework, …). It is
the responsibility of the end user to select proper pump foundation
type. Noise level and vibrations transmitted by the machine depend on
the quality of foundation.
Following rules are general instructions that should be respected :
- Base frame or pump matting plate should be fastened to a rigid
foundation with no risk of distortion while the pump is running.
- Make sure that the foundation concrete is of sufficient strength (min
quality X0 to DIN 1045). Generally, the weight of foundation is around 3
times the pumpset weight. With pump set dimensions and concrete
density it is then possible to calculate the dimensions of the required
foundation block.
- Surface under pumpset should be flat and should not create any
distortion of base plate after tightening of foundations bolts. If surface
quality is not sufficient, add shims between ground and base plate.
Distortion on base plate surface should be limited to 0,4mm/m after the
baseplate is definitively fastened to foundations.
Coupling alignment is checked before shipment (pumps and
motor deliver ed on a common baseplate) If coupling is not
correctly aligned after installation works are done this indicates that the
baseplate has become twisted and leveling should be corrected by re-
shimming.
Even if foundation works have been done with care, it is necessary to
check coupling alignment after the baseplate is definitively secured to
the foundation.
7.1.2 ANCHORING
Chemical anchoring device should be preferred to fasten a baseplate on
an existing foundation.
Anchor bolts can be used if foundation block is to be built.
1 – Anchor bolt
2 – Baseplate
3 – Concrete foundation block
Folded steel fabricated baseframes will be grouted to insure its rigidity.
Using of shrink free grout is the most efficient. Grouting ensures correct
positioning of the baseframe and reduces vibrations transmission to civil
work. Foundation work surface preparation and leveling of baseframe
will be performed in the state of the art and should be done before
grouting of the baseplate.
Foundation bolts should be fully tightened only after the
grout has cured.
Installation without foundation :
1 – Intermediate plate
2 – Nut
3 – Leveling element
4 – Foot base
5 – Washer
6 – Fastening nut
7 – Washer
8 – Baseplate fastening screw
7.1.3 POSITIONING
Pump baseplate (cast iron base plate or fabricated steel baseframe)
should be installed horizontally to ensure bearings lifetime and proper
flow of pumped fluid.
7.1.4 COUPLING ALIGNMENT
Pumpsets assembled with a flexible coupling must be aligned after the
baseframe has been definitively fastened to the foundation. Use low
thickness shims (0,2 to 1 mm) to modify coupling alignment. Adjust the
motor height first. Sometimes it is necessary to add shims under pump
feet too.
Aligment of coupling should be performed with particular care
when the pumpset is installed in an hazardous area. Correct
alignment will avoid abnormal increasing of the pump and motor ball
bearings temperature.
Thermal expansion : the pump and motor will normally have to be
aligned at ambient temperature with an allowance for thermal
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