TPi May 2015

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26 Tube ProducTs InTernaTIonal May 2015
Increasing the durability and service life of
district heating networks
By upgrading the quality of steel pipes
that constitute the core of a district
heating (DH) pipe system, and further
developing weld joints in the form of a
Logstor PlateJoint for the largest pipe
dimensions, Logstor has taken another
step towards increasing the service life
in supply networks for DH stations. A
service life of 30 years is required by
standard, but the expected service life
is now 50 years or more.
The P235GH steel quality has been
tested and documented for use at higher
temperatures. During 2015 Logstor will
convert to a new standard, supplying
pre-insulated pipes with steel pipes in
quality P235GH for the entire range of
dimensions.
The transmission pipes are the
‘highways’ of the DH network. Even
a minor interruption here has huge
consequences for many, if not all,
consumers of the DH company. The
pipes must work without interruption, 24
hours a day, each day of the year. High
quality joints in the pre-insulated pipes,
while welding and installing casing joints
on-site, is essential.
Logstor has constantly developed its
casing joint systems, aiming to produce
a casing joint with the same strength as
the pipes it joins. For large dimensions,
with casing pipes of 780mm and larger,
the company has introduced the next-
generation Logstor PlateJoint.
The PlateJoint is produced from an
extruded HDPE plate, and can therefore
be supplied as a plate, which makes
handling during transportation and
installation easier.
Installation is simpler and faster,
conducted as a one-unit procedure,
where casing joint and outer casing
are welded by means of a computer-
controlled process. The quality process
is recorded and digitally documented.
PlateJoint meets the technical
requirements specified in the standard
for casing joints for DH pipes.
Logstor PlateJoint has been chosen
for the Lisbjerg pipeline project, near
Aarhus in Denmark. This involves a 10km
transmission line with OD 800/1,000mm
to connect a new CHP plant to the DH
network in Aarhus. The project was
initiated in 2014 and will be completed
in 2016.
logstor a/s – Denmark
developments
products &
Installation of Logstor PlateJoint in Lisbjerg