Cast Iron Pipe Technology - Duktus

The Spirit of the Original
Cast Iron Pipe Technology

2
THE SPIRIT
The company
Quality is our tradition -
Buderus cast iron pipes for more than 100 years
Buderus has been producing pipes in Wetzlar
since 1901. In the beginning cast iron pipes were
produced using the sand-casting process. As one of
the fi rst pipe manufacturers, Buderus adopted the
tube spin-casting process from Lavaud in 1927. And
today Buderus is one of the leading manufacturers
of ductile cast iron pipes in Europe.
Buderus Gussrohrtechnik represents highest
quality and state-of-the art production. It stands
for fl exibility and responsibility, which starts with
engineering consultations for projects and continues
in production and support on the construction
site where the pipes are installed. Cast iron pipe
technology is supported by a team of qualifi ed
employees, who assume the responsibility for
their products – the pipes and their connections
– by utilizing their ideas, the capabilities in applying
the material and their knowledge about pipe
constructions.
Buderus Gussrohrtechnik uses a quality
management system certifi ed in accordance
with DIN EN ISO 9001. Products and production
processes are frequently monitored by the
Materialprüfungsamt [material test offi ce] Nordrhein-
Westfalen.
Additionally, Buderus Giesserei Wetzlar GmbH uses
an environmental management system certifi ed in
accordance with DIN EN ISO 14001.

OF THE ORIGINAL
Ductile cast iron pipe systems
Ductile cast iron – an innovative material
Ductile cast iron pipes are now essential for the transport of our most
valuable food component, drinking water. This is a clear indicator for
the outstanding characteristics of the proven material.
What does ductile mean?
Ductile means shapeable. Ductile cast iron material is not rigid, it can
bend based on its structural condition.
This makes it strong!
Ductile cast iron – a tough iron-carbon material, with a carbon content
that is mainly present as graphite in a free form – is a development
based on grey cast iron, which was used in the past.
In contrast to grey cast iron, which contains the free graphite in lamina
shape, the ductile, shapeable cast iron contains graphite spheres
– the spherolites – which positively infl uence the characteristics of the
primary structure. This increases the strength characteristics of ductile
graphite iron in comparison to grey cast iron.
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PIPES AND FITTINGS
4
Socket pipes made from ductile cast iron for
drinking water and waste water
High strength and extreme overlap
Root resistant
Integrity even at high internal pressures,
vacuum and high ground water levels
High cost effectiveness due to long product
life
Defl ection of the connections up to 5°,
depending on the nominal diameter
Socket pipes made from ductile cast iron for
drinking water and waste water with cement mortar
lining (ZMU)
High mechanical strength
Can also be used in soils with rock content
(up to 100 mm diameter) and for strongly
aggressive soil conditions
Soil exchange is not necessary, excavation
soil must not be removed
Socket pipes made from ductile cast iron for
drinking water and waste water can be delivered in
accordance with the following external protection
types:
Fittings
Zinc coat with cover coating
Zinc-aluminum coat with cover coating
Cement-mortar coating
WKG coat
Other designs on request
A comprehensive fi tting assortment is
available to provide a complete system
solution for all applications.

Plan by utilizing the capabilities of ductile cast iron
pipes from Buderus.
Our advantages are as certain as the ductile pipes
are safe in the ground.
Technical advantages
Cast iron pipes can handle high static stress.
Due to the TYTON ® connection, they can be
deflected, they are inured against position changes,
they are root resistant and they withstand high
internal pressures and surrounding groundwater.
Innovative internal and external coatings protect the
pipes against attack by water and soil.
Ecological advantages
Ductile cast iron pipes are almost completely made
from recycled material and are therefore recyclable.
The internal lining consists exclusively of cement,
sand and drinking water.
Economic advantages
• high installation performance due to large
construction length
• long product life due to innovative internal and
external coatings
• reuse of the excavation material for pipes with
external cement-mortar coating
• simple and therefore fast installation
SUMMARY OF ADVANTAGES
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DRINKING WATER PIPES
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Water as a strategic
resource
This foundation of all life is not evenly distributed in
the world.
The main objective is to supply people with clean
drinking water. Even if you are living in an area with
plenty of water, please do not waste a drop of this
valuable food component.
The utilization of ductile cast iron pipes for the
drinking water supply ensures for many decades
now that this main food component is safe and
reaches the user unchanged.
Functional safety and cost effectiveness are the
main criteria for pipe systems made from ductile
cast iron pipes. The wide application variability
is another criterion or in other words, another
advantage of the ductile drinking water systems.
The ductile cast iron material and the TYTON ® pushin
socket connections provide outstanding safety
reserves to meet the requirements of a stable and
long-lasting drinking water supply.
Depending on the requirements, BLS ® and BRS ®
push-in socket connections are available as
longitudinal force-fi t push-in socket connections.

Safety, tightness, long
product life
Waste water must safely arrive at the treatment
facilities, because clean groundwater is vital! The
use of ductile waste water pipes provides you this
safety.
Why are ductile waste water pipes safe?
Because they do not leak.
Groundwater cannot penetrate the channel.
Materials and connections prevent the leaking of
waste water and therefore the contamination of soils
and groundwater. They can absorb high external
loads easily, which are caused by earth pressures
and traffi c loads. They provide high safety reserves
to compensate for unpredictable loads.
A clear economic advantage is the extreme long
product life.
Waste waters are aggressive, and that is no issue
for waste water pipes from Buderus, because the
internal lining with high alumina cement-mortar
ensures that the pipes are protected even against
strongly biogenic sulfuric acid attacks.
Buderus ductile cast iron waste water pipes and
fi ttings can be used almost everywhere, among
others as gravity lines and for pipes through drinking
water protection areas.
One guarantor for the safety is the TYTON ®
push-in socket connection. This connection is
defl ectable. It works like a joint and follows the soil
movements, without transferring bending forces
to the next pipe or fi ttings. And it is root resistant.
The TYTON ® ensures that the pipes are protected even against
Buderus ductile cast iron waste water pipes and
fi ttings can be used almost everywhere, among
others as gravity lines and for pipes through drinking
push-in socket connection. This connection is
defl ectable. It works like a joint and follows the soil
movements, without transferring bending forces
to the next pipe or fi ttings. And it is root resistant.
push-in socket connection provides
tightness against high internal pressures and against
surrounding groundwater.
WASTE WATER PIPES
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COATINGS
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Well coated
Buderus cast iron pipes for drinking water and
waste water are reliably protected against external
corrosion attacks.
A zinc coat with cover coating or cement-mortar
coating qualify the cast iron pipe for almost all
existing soil types.
The following coatings are available:
• Zinc coat with cover coating
• Zinc-aluminum coat with cover coating
• Zinc coat with cement-mortar coating
Pipes with zinc coats and cover coating when used
in combination with an additional heat insulation
(WKG) can also be used for pipes that are subject
to frost or heat losses.

Well lined
Pipes that are used for the transport of drinking
water receive an internal cement mortar lining based
on blast-furnace cement (HOZ), while waste water
pipes are covered with a cement mortar lining based
on high alumina cement (TZ).
These are purely mineral linings, which consist of a
cement sand water mixture.
They are attached to the pipe by a rotational spin
process. The bonding area is protected by an epoxy
resin lining.
Other internal linings available on request.
LININGS
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CONNECTIONS
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Good connections are
important
Pipe systems are used as part of the supply and
disposal pipes and that is exactly the reason why
pipe connections are so important. The effi ciency of
the pipe depends on its reliability. Buderus uses the
proven TYTON ® push-in socket connection for all
ductile pressure pipes.
It is root resistant and highly resistant to stress.
The tightness of the pipes is also guaranteed by the
TYTON ® push-in socket connections for high internal
pressures, vacuums and high groundwater levels.
A specially shaped sealing assumes the sealing
function. The sealing consists of a soft and a harder
rubber mixture. The sealing in the sealing chamber
is pre-pressured after the socket has been put
in place. A design coordination between sealing
chamber, sealing rim and pipe diameter results in a
high deformation of the sealing and therefore in a
high contact pressure on the sealing surface. The
harder, claw shaped ring part, which is positioned
in the fastening groove of the socket, keeps the
sealing in its position during the insertion of the pipe
end and it provides the same service later against
stress due to internal pressures.
Defl ection of the connections up to 5°, depending
on the nominal diameter.
However, the TYTON ® push-in socket connection
does not have a natural longitudinal force-fi t.
The following longitudinal force-fi t designs of the
TYTON ® push-in socket connection are available if
the forces created by the internal pressures in the
pipe cannot be absorbed by the concrete anchor
block.

The longitudinal force-fi t BRS ® push-in socket
connection (Buderus-Restrain-System) is a
development based on the proven TYTON ® - SIT
connection. The result of this development is
the TYTON ® - SIT- PLUS ® connection. The BRS ®
connection with its friction force fi t is highly resistant
to stress due to the sealing and can therefore be
used for extreme applications. The pipes with a
length of 6 m can be installed in a radius a short as
115 m because the push-in socket connection is
defl ectable up to 3°. This reduces the requirements
for fi ttings and the installation time. The innovative
connection technology and the friction force-fi t of
the BRS ® push-in socket connection provide a large
number of advantages and application possibilities,
which far exceed the application options of the
TYTON ® - SIT connection.
Quick overview
• Replacement for concrete counter bearings
• Suitable for loads of up to 32 bar
• Simple and fast installation
• Defl ectable up to 3°
• Extensive fi ttings program
The longitudinal force-fi t BLS ® push-in socket
connection (Buderus-Lock-System) provides a form
fi t and is highly resistant to stress, which means
it can be used for extreme applications. A welding
bead on the insertion end transfers the shearing
force through bars to a safety chamber, which is
attached to the socket. The proven TYTON ® sealing
provides tightness for the connection. The BLS ®
push-in socket connection is defl ectable up to 5°
and is therefore superior to all other longitudinal
CONNECTIONS
force-fi t push-in socket connections. Narrower curve
radius can be achieved during installation. These
characteristics are desirable when pipe lines get
installed with modern trench processes, plowed in
by rocket plows or if they are installed as culvert
pipes in rivers. The BLS ® connection is the optimum
solution for pipes above ground, such as bridge
pipes, whose connections must absorb length
changes due to temperature variations.
Quick overview
• Replacement for concrete anchor blocks
• Horizontal drilling
• Plowing with the rocket plow
• Trenchless exchange of pipes on the same track
with the press-pull process
• Burst lining process
• Culvert pipes
• Bridge pipes
• Collector pipes
• Pipe systems for snow making facilities
• Turbine pipes
• Fire extinguisher pipes
• Pipe relining
• Defl ectable up to 5°
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TRENCHLESS INSTALLATION
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Trenchless construction processes for the
replacement of pressure pipe systems are important
for inner-city installations and culvert construction in
rivers.
The application shows a clearly increasing trend,
because it is much more cost effective if compared
to the open construction and the environmental
impact is significantly lower.
Ductile cast iron pipes with longitudinal force-fit
BLS® connections are especially qualified for
trenchless pipe installations based on their high
stress-resistance.
Press-pull process
This process pushes the old pipe out of the ground
by using a pull linkage and a special pull or pressure
head, and it inserts during the same process the
new ductile cast iron pipe with the BLS ® push-in
socket connection and cement-mortar coating into
its place. A nominal diameter increase is possible
when using this process.
The press-pull process provides high efficiency,
speed, reliability and therefore high cost efficiency.
Horizontal directional drilling
The controlled horizontal drilling technology is for
the last 15 years a fixture for pipe installations and
many other areas. It was developed in the US in the
seventieth for deep drilling applications. It is used
as trenchless installation technology for pipeline
constructions. The drilling technology has been
accepted at a fast speed.
The pipes are installed without an installation trench
by using a drilling system.

PROJEKT IRGENDWO
Rather than implementing extensive excavations, a
pilot drill hole will first be calculated and executed.
Obstacles and direction changes are not important,
because the drill head tip has a functionally
controlled sensor. This means that the drilling
progress can be monitored and controlled.
This is followed by the trenchless installation of the
supply pipes. Only a start and a target excavation
have to be established.
Burst lining
The burst lining process is an environmentally sound
trenchless replacement of pipelines through the
same routes. The old pipe is burst with the help of
a burst head and is pressed into the surrounding
soil. The resulting cavity is enlarged in such a way
that a pipe with the same or a larger diameter can
immediately be inserted. The burst lining is divided
into a dynamic and a static process.
Rocket plow process
The rocket plow is used to install pipes in new
routes. The rocket plow is a development based on
the pipe and cable plows, which have been used for
more than 30 years for the installation of cables and
flexible pipes.
The rocket plow process is suitable for ductile cast
iron pipes up to a nominal diameter of DN 300.
The components of the process are basically the
pull machine with a cable winch and a plow. The
most important machine part of the plow is the plow
blade. The plow is connected to the pull vehicle by a
steel cable. A start hole, which slopes downwards,
leads the pipe to an appropriate installation depth
and there it is connected to the plow blade. During
this process, the plow blade thrusts the soil to the
side in the area of the pipe zone due to the pull
forces of the cable winch. This creates a cavity
which is used to immediately install the pipe.
The plow process is especially suitable for rural
areas with low population densities where large
pipe lengths with few connections are required. This
process is currently only used for the installation of
pressure pipes.
Pipe relining
The consumption of drinking water and therefore
the generation of waste water have continuously
decreased during the last years and decades.
This is the reason why the long pipe lining has
become more important, because smaller pipe
diameters can now be utilized due to the lower
water quantities. And this is why the long pipe lining
is increasingly used.
This process pulls or pushes ductile cast iron pipes
into existing pipes that are no longer suitable for
water transport. Excavations are only required at
the start and at the target location. This results in
relatively small efforts for civil engineering and for
road construction and it has little effect on traffic and
the residents.
The cavity between old and new pipe can be
insulated after completed installation.
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TURBINE PIPES
Power from hydroelectric power plants means
clean energy.
Turbine pipes are often installed in extreme
environments. However, a fast and safe installation
is still possible with ductile cast iron pipes,
because the connections guarantee good bending
characteristics and the pipes can be installed without
problems even if the weather is bad.
The surrounding area can easily be re-cultivated,
because only small trench excavations
are required.
The outstanding stability
characteristics of the ductile
cast iron pipes and the
push and pull safe
connections guarantee
power plant pipe
operations free of
malfunctions.
For many
generations.

The lack of effi cient fi re extinguishing capabilities
often results in human and economic disasters.
A fi re extinguisher pipe is non-fl ammable, absorbs
stress and makes water for fi re fi ghting available
when needed.
Due to their high safety reserves against internal
pressure stresses (pressure surges) and
external loads, ductile cast iron pipes are
used for fi re extinguishing systems
at airports, industrial facilities and
street and railway tunnels. All
available connection types
and external protection
types may be used
depending on the
requirement profi le.
FIRE EXTINGUISHER PIPES

SNOW MAKING FACILITIES
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The use of snow making facilities and therefore the
guarantee that the ski slopes are ready for skiing
are mandatory for attractive ski villages to ensure
the most important economic factor for tourism
dependent operations.
The technical advantages of ductile cast iron pipes
are the basis for the sales success of this special
application.
The basis for the effi cient functioning of a snow
making facility is a safe water supply, which meets
all requirements at high and medium altitudes and
which can withstand very high pressures.
Buderus has delivered more than 1000 snow
making pipes throughout Europe during the last
years. The robustness of the material, the mobile
socket system and the fast and easy installation
and assembly have made Buderus and its sister
company, Tiroler Röhren- und Metallwerke AG, the
market leader of pipes and fi ttings for snow making
facilities.

Heat insulated cast iron pipes (WKG pipes) with
longitudinal force-fi t push-in socket connections are
used as bridge pipes.
The heat insulation prevents freezing of the fl ow
medium even if it does not move for a longer time.
A support heating can be integrated if required.
The WKG pipe system consist of pipes and
socket bends (MMK, MMQ) made from ductile
cast iron in accordance with DIN EN 545 (water)
or DIN EN 598 (waste water) with TYTON ® pushin
socket connection in accordance with DIN 28
603, longitudinal force-fi t if required. The pipes
are covered with a heat insulation made from
FCKW free polyurethane (PUR) hard foam with an
average total density of 80 kg/m 3 . For open pipes
(FL), the hard foam is protected against weather
related impacts by a roll fold coat pipe made from
galvanized steel sheets in accordance with DIN 24
145 or stainless steel. For earth covered pipes (EL)
that are subject to frost, the hard foam is protected
by a coat pipe made from PE-HD in accordance with
DIN 8074/8075.
HEAT INSULATED
PIPES
17

QUALITY
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Certified quality
management system
The quality of the manufactured products and
the satisfaction of the customers is the highest
company goal for Buderus Gussrohrtechnik.
Buderus Gussrohrtechnik uses a quality
management system certified in accordance with
DIN EN ISO 9001.
The products and production processes are
frequently monitored by the Materialprüfungsamt
[material test office] Nordrhein-Westfalen.
Additionally, Buderus Giesserei Wetzlar GmbH uses
an environmental management system certified in
accordance with DIN EN ISO 14001.
The comprehensive quality assurance system starts
with the chemical analysis of the raw and auxiliary
materials, because the melting and the treatment
of the molten iron require a very high pureness
and uniformity of the raw materials, monitoring of
the melting process, the stability of the chemical
composition and the seeding.
The pipe manufacturing process must especially
monitor the solidification and shrinking
characteristics of the ductile cast iron. The review
of the annealed pipes must test the material
characteristics, which are defined in DIN EN 545 (for
drinking water pipes) and DIN EN 598 (for waste
water pipes).
The sockets and the insertion ends of the annealed
pipes are tested with limit gauges, the wall thickness
is measured with calipers. All pipes are subject to a
comprehensive visual inspection for internal and external
defects. Depending on the pipe and the diameter,
the pipes must withstand the specified test
pressures during the internal pressure test with water.

Cement-mortar lining
The cement-mortar linings of the pipes are also
subject to the rigorous quality controls. Depending
on the nominal diameter, the required coat thickness
must be met, in addition to a test of the basic
materials of the fresh mortar.
External coating
The external coating is also subject to such a
rigorous control. The ductile cast iron pipes from
Buderus always receive an external coating, which
consists of a zinc coat and a cover coating. It is also
possible to optionally cover Class 40 pipes with
a zinc-aluminum coat with cover coating (Buderus
Zink-Plus ® ) to increase corrosion protection.
A high quality plastic modified cement-mortar
coating with a high mechanical resistance and a
thickness of 5mm is available for use in strongly
aggressive and rocky soils.
The final inspection is performed after the pipes are
marked. The material is marked as “ductile cast
iron” by a parallel indentation on the inside of the
socket. It is approximately 3 mm deep.
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Buderus Giesserei Wetzlar GmbH
Cast Iron Pipe Technology
P.O. Box 1240 D-35573 Wetzlar
Phone: +49 (0) 64 41 - 49 22 60
Fax: +49 (0) 64 41 - 49 16 13
E-mail: manfred.hoffmann@gussrohre.com
www.gussrohre.com
BGW/RV • 112 • 03/06 • e 2 000 • DN