Shaft Bearings; Function; Installation And Electrical Connection; Location - Wilo MMI50V Instrucciones De Instalación Y Funcionamiento

ENGLISH
6.1.1.5 MOTOR ASSEMBLY TYPE TH AND MOTOR FRAME
V18:
A bearing bracket fitted with one over-sized ball bearing is used to
support axial load. This arrangement is available for pumps length above
1920 mm under mating flange. The ball bearing is lifetime lubricated.
Power is transmitted through a rigid coupling to the pump shaft
(clamped).
6.1.2

SHAFT BEARINGS :

A bearing is located in pump back cover as close as possible to the
impeller to limit cantilever effects on the shaft.
One or more additional bearings are added along the shaft depending on
the total length of the pump.
Several friction materials are available : Silicon carbide, bronze, PEEK or
Graphalloy®.
Two bearing lubrication principles are used :
Flowded Fluid injection through the bushing
If waste water lubrication is used, fluid pressure will be maintained
between 0.5 and 1bar corresponding to a flowrate of 50l/h.
12

6.2 FUNCTION

Pumps are usually run at 1450 or 2900 RPM depending on the requested
head.
They are designed with a normalized hydraulic according to EN733 or
ISO2858, a long shaft and depending on chosen variant with a bearing
bracket located above mating flange. This bearing bracket is supporting
pump axial loads.
- Hydraulic back cover must remain wetted in any case. Minimum
level of liquid must ensure that the entire hyraulic is totally
flooded.
- Motor assembly is designed for dry application.
- Some bearings can be added between columns flanges for proper
shaft alignment.
An 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.
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
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.
The installation of the pump must be carried out correctly, otherwise the
performance will not be optimal and the lifetime will be shortened (wear
of bearings, impeller, motor ball bearings, vibration, noise, ...).
AND ELECTRICAL