Water & Wastewater Asia March/April 2019

26 | FROM THE GROUND
The 38-ton pump with an impeller diameter of 1,905mm
One of the original KSB ME plants that was installed when the plant was first constructed
of Montreal requested that KSB submit a
tender for another pump of the same design
and capability.
Unfortunately, after such a long interval, the
original pumps were no longer in production.
However, KSB circumvented the issue by
coming up with a plan that involved making
an updated replica – a proposal that ended
in them winning the order.
KSB’S MEF PUMP
Constructed in accordance with customer
specifications, the KSB MEF pump is a
vertical split-case, single stage pump, that
is an updated version of the original pumps
supplied in 1975.
The footprint and layout of the new pump
resembles its older counterparts, but up-todate
seals and optimised hydraulic elements
have enhanced its reliability and improved
operating efficiency. Duplicating the older
pump configuration also simplified the
installation of the new unit in the Charles-
J.-Des Baillets high-pressure pump gallery.
Having secured the contract, KSB
manufactured the new MEF pump in Brazil,
and shipped out the 38-ton pump with an
impeller diameter of 1,905mm in late 2013.
With a drive shaft measuring 5 metres in
length and operating at a fixed speed of 400
rpm, it delivers 4.2m³ per second at a head of
67m. Initially planned to be used as a backup
unit, the pump also operates in parallel
with the existing large-capacity pumps. Due
to its size, the pump had to be disassembled
for shipment and reassembled on site.
In April 2015, work commenced on the
assembly and installation of the pump at
the Charles-J.-Des Baillets water filtration
plant under KSB’s supervision. Between
May 2015 and April 2016, installation of the
5,500 HP synchronous motor and line shaft
was performed by the mechanical contractor.
The next phase was the commissioning
and configuration of the control panels and
auxiliary electrical components undertaken
between April 2016 and September 2017,
with performance and acceptance tests of the
pump conducted in October 2017.
The hydraulic acceptance tests were
performed on the new pump unit with
the scope of the tests being to verify the
contractual efficiency guarantee point of 87
per cent at 4.2 m³/s. Summarising the key
results, at the rated flow of 4.2m³ per second,
the pump efficiency was 90.4 per cent; 3.4
per cent greater than the guarantee efficiency
of 87 per cent. The results show that the
performance of the pump GP5 fulfilled the
contractual guarantee obligations.
CHALLENGES
Installing the new pump set was not without
its challenges, given that the area allocated
was between two existing units and involved
a three storey, open high-pressure pump
gallery, and the excavation of foundations to
accommodate the water intake pipework and
pump volute.
The pump gallery was constructed on three
storeys with the motors and the control
panels mounted on the upper floor and the
pumps three storeys directly below on the
bottom level. A five-metre-long drive shaft
from the 5,500 HP motor on the upper
floor couples to the pump below. Because
the new pump had the same hydraulic
configuration as its older counterparts, it was
installed alongside them in exactly the same
arrangement.
KSB engineers played a significant
role in overseeing the installation and
commissioning of the new pump as the
process was somewhat complicated by
the ingress of water from the adjacent
underground supply reservoir. Each pump
intake was secured by two sets of stop logs,
as compared to large gate valves, creating a
serious problem with water infiltration into
each intake chamber in which the pumps
are mounted. Thus, it was necessary for
the safety of the engineers and the
construction personnel to continually pump
water from the foundations during the
construction of the intake chamber of the
new pump.
CUSTOMER SATISFACTION
According to an engineer from the City of
Montreal’s water department, the addition
of the new pump provides more redundancy
to the system.
Water & Wastewater Asia • March / April 2019