TPi October 2010

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October 2010 Tube Products International 57
pipesPVC, PE & XLPE
began life in 1919 when Lt Ernest Tribe of
the Royal Engineers founded the Victory
Pipe Joint Company. His Victaulic joint
was invented in 1922 and was the
basis of what is still today an extremely
robust and reliable jointing method for
pressure pipe. This was also the branch
of the group that in 1930 gave birth to
the Viking Johnson high tolerance pipe
coupling, suitable for joining dissimilar
pipes.
This was also a critical period in the
development of plastic pipe systems.
Polyvinyl chloride pipe was in production
between the wars, although it was
largely reliant on fabrication of relatively
short pipe lengths. The way forward lay
in producing plastic pipes by continuous
extrusion, and by the time extrusion
technology was maturing in the 1950s,
high density polyethylene (HDPE) had
appeared on the scene. The arrival of
HDPE offered a superior material to PVC
for piping pressurised water.
The inherent strength of HDPE was
significant in its suitability for water
and gas pipes but above all its ductility
– resistance to brittle failure – was
key. Coincidentally, ductile iron was
also introduced in the UK as a pipe
material in the 1950s and has remained
a competitor to PE since then.
As PE pipe systems began to be
accepted and installed by the water and
gas utilities, the Glynwed companies
(the antecedents of today’s UK
manufacturer GPS PE Pipe Systems)
were prominent in developing new
products and manufacturing methods.
These included, in 1979, the UK’s first
electrofusion joint, with electrically
heated wires embedded in a moulded
coupling.
In the following year the PushFast spigot
and socket system was introduced, and
by the end of the 1980s the group had
brought in the ‘Rolldown’ trenchless
pipe installation technique, high strength
PE100 pipe and had manufactured the
UK’s largest diameter PE pipe. This
was a 630mm pipe installed by Thames
Water at Blake’s Lock, Reading.
Over the next decade GPS was
responsible for taking the application
of PE pipe systems in a number of
new directions. In 1994 the group
produced the first skinned PE pipe,
for the Severn Trent Water Authority.
Providing protection for the pipe surface
during installation and enabling a clean
surface to be presented for electrofusion
jointing, this innovation was developed
into the GPS peelable pipe, Secura-
Line. This was quickly followed by a
multi-layer barrier pipe for petrol and the
first barrier pipes for potable water in
contaminated land, Protecta-Line.
From very early beginnings pipe
systems have diversified in terms of
their materials and design, undergoing
rapid development in recent decades.
In the water and gas industries, this
has culminated in HDPE pipe systems
that offer an extremely long service
life, high performance and installation
benefits. There are currently no better
alternatives to take their place. On this
basis innovative manufacturers, such as
GPS PE Pipe Systems, continually seek
to offer new solutions in water and gas
distribution using this versatile material.
GPS PE Pipe Systems – UK
SF PVC (thermo plastic PVC) duct from
Novaflex features a special molecularly
bonded construction, for reduced
turbulence and increased flow efficiency.
The duct is suitable for many industrial
applications, including the transport of
particles and gaseous media.
The duct is constructed from premium
clear polyvinyl chloride, allowing for
continuous visual monitoring, and is
manufactured with FDA approved
materials. It is suitable for light duty
Clear PVC duct
material handling, and has good
resistance to oil, alkali and acids, as
well as being very flexible, with good
abrasion resistance.
The duct is available in sizes from 1.5"
to 24", in 25 and 50ft lengths (up to 8"
diameter) or 20ft lengths (10" diameter
and greater). The temperature range is
20°F to 165°F.
Novaflex Group – Canada
Stewarts and Lloyds was formed in 1895, by
the merger of A&J Stewart and Menzies Ltd
and Lloyd and Lloyd Ltd
A stack of modern
plastic pipes