74
Tube Products International October 2012
water, drainage & underground
PE 100: a new awareness
A new aqueduct brings important
advantages, especially in terms of health
conditions. A project by Ritmo SpA
shows this concept: the Hogenakkal
Mitigation Water Supply & Fluorosis
Project (HWS e FMP).
In the south of India, in the districts of
Dharmapuri and Krishnagiri, an area with
great rural villages and a high population
density, the supply of potable water
is extremely difficult, especially during
the summer drought. The population is
bound to withdraw the water from the
subsoil, where the aquifer stratums are
polluted by high fluorine concentrations.
The extended consumption of this
polluted water involves risk of disease.
In 2008, the Tamil Nadu government
approved and began the Hogenakkal
Mitigation Water Supply & Fluorosis
project, allocating the necessary
funds for the construction of a water
withdrawal system from the Cauvery
river, water treatment, collection basin,
and a distribution pipeline to the many
districts.
The first major step was the
establishment of a pool of three large
contractors to which the projects were
assigned. These were divided into five
stages, so that the conclusion of this
massive worksite would be reached as
soon as possible.
One of the most important aspects of
the project was the choice of materials
to build the infrastructure.
HDPE is a novelty in many
areas of India, and there
is an incorrect perception
about plastic pipes, that
they are considered fragile.
The reason for this is that
in the past, many weldings
had been made by unskilled
operators, using unsuitable
equipment. The results were
predictable, but they now
belong to history.
Lipi Polymers Pvt Ltd,
an Indian company with
qualified personnel with
expertise in HDPE and other
plastic materials, listed
the many advantages and
strengths of plastic pipes in this gigantic
project: time length, lack of toxicity,
resistance to corrosive materials,
among others, all of these proven by
tests performed in a laboratory using
welding samples made by Lipi Polymers
staff. The tests persuaded the technical
commission to approve the use of HDPE
pipes in the Hogenakkal Mitigation
Water Supply & Fluorosis project.
Throughout the 9,000km of the
infrastructure, many types of pipes
are being used: mild steel for large
diameters, ductile iron from OD 355
to 500mm, and PE100 PN6 for small
diameters up to OD 315mm. The overall
HDPE percentage used in the entire
pipeline is 84%.
More than 50 welding
machines are being used,
all of them manufactured by
Ritmo, an Italian company with
over 30 years of experience in
plastic welding. Butt weldings
from OD 40 to 315mm were
assigned to the Delta line.
The Delta 315 is able to
weld fittings such as elbows,
tees, Y-branches and flange
necks without any additional
equipment, by simply fixing
the clamps’ drag bar.
The Delta 315 includes a
machine bodywith four clamps
and two hydraulic cylinders
with fast non-drip couplings;
a Teflon-coated heating plate,
with built-in thermometer
that checks the working temperature,
and a high-precision electronic
thermoregulator; an extractable milling
cutter, with safety micro switch; an
electro-hydraulic gearcase, supplied
with a control lever to open and close
the clamps, maximum pressure and
discharge valves, hydraulic connection
hoses and a timer; and a milling cutter/
heating plate support. The machine
standard set includes adapters from OD
90 to 280mm. A tool for flange necks is
available on request.
Welding of electrofusion fittings from
OD 20 to 125/160mm was assigned
to Ritmo’s Elektra Light model. Elektra
Light is a universal electrofusionmachine
(from 8 to 48V), suitable for welding
pipes/fittings for the transportation
of gas, water and other fluids under
pressure. The Elektra Light is compact
and lightweight, so it is extremely easy
to carry around. The machine has also
an in-built memory of up to 350 welding
cycles.
The welding reports are downloadable
to a USB key through the DB9M/
USB adaptor, and afterwards can
be transferred to a PC/laptop to be
managed by means of specific software.
The welding machine is available in
two versions – with or without optical
scanner – and is arranged with a
universal model of adapter (no other
adapters are needed).
Ritmo SpA
– Italy
The project will bring potable water to 3.1mn people
