for Yachts
Innovative Gear Solutions in Naval Propulsion Systems
Innovative Power Transmission
The basic factors for a long lasting success in the production
of industrial goods are innovative technology, reliable
customized products, a creative management, and a human
resource policy enabling RENK employees to identify
themselves with “their” product.
An additional most important part of the RENK philosophy
is the close relationship to our customers, giving us the
possibility to understand demands and developments.
RENK as a world leader in developing and manufacturing
highly sophisticated gear box systems faces the challenge
to continuously develop new technologies in the field
of propulsion engineering and to implement such new
knowledge into its product.
Research and development is one of our most important
tasks in order to provide our clients always a product
which is based on the latest state of the art with respect to
performance, reliability and design. Following the above,
RENK has been succeeding in setting milestones in power
transmission engineering for decades.
RENK does not only sell high-tech products, but also
makes sure that its gear boxes can be operated to the full
satisfaction of the customer without any problem for many
years. If necessary, our own field service network ensures that
specialized technicians are available on short notice – at any
place in the world.
One of the key factors (for the success) of our company
is the continuous education and training of our staff.
Qualified employees have always enjoyed an interesting and
challenging job with RENK.
Our goal is to further expand our current market position
through technological excellence and customer satisfaction.
Philosophy
CODAD gear box
Type BSL 2 x 130/140
during final assembly.
COGAG gear box BUS 2 x 122 in light
weight cast aluminum design on the RENK
test bench.
Double stage CODOG gear box BUS 110
ready for dispatch.
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Design
High-end reduction gear systems are consisting of a number of high accuracy
components. Decades of experience, the latest design and production methods
and quality without compromise for gears, bearings, casing structures,
clutches and controls are the base of any
Megayacht gear system delivered by RENK.
Beside conventional
single in/single out
gear boxes for gas turbines
or diesel engines and based
on its vast experience in the field
of Navy gear systems, RENK can also
provide so called “combined gear box systems”.
COMBINING GEARS
CODAD –
COmbined Diesel And Diesel.
Two or more diesel engines drive one
common propeller or water jet.
Diesel engines at equal, or different rated
power as a father and son arrangement.
COGAG –
COmbined Gas turbine And
Gas turbine.
Combination of two or more
gas turbines to one common
output shaft. As option,
the gas turbines can be
flange mounted to the gear
box casing (cantilever design).
CODAG – CODOG
COmbined Diesel engine
And/Or Gas turbine.Both, diesel engine
and gas turbine driving one common
output shaft, which allows for each prime
mover to be operated close to its optimum
specific fuel oil consumption.
LOW NOISE GEARS
All type of specially configured Megayacht
gears include reduced noise radiation
measures adjusted to specifications. Even
the “super silent gear” is available from
RENK.
This combined gear box arrangements,
especially, offer the ship designer all options
to create a most intelligent power management
optimized for the individual speed profile
based on the ship-owner’s requirements.
To this end, overall fuel oil consumption of the different
combinations of prime movers,
and the different propulsion modes are taken into
account. The appropriate selection of the most
suitable arrangement in combination with a given
speed profile for the Megayacht has a significant
influence on bunker capacity, operating range etc. and
thus on the overall yacht design.
To safely engage the different propulsion modes and take
care of a smooth and reliable change over between the
modes, RENK develops and builds tailor made computer
control systems for such combined propulsion systems.
The interactive control display gives a comprehensive local
overview of the actual operating condition and allows for
any desirable local control operation.
RENK as a gear box manufacturer who is specialized
in design and tailor made construction of gear box
arrangements is prepared to support designers, shipyards,
or engine manufacturers already in the very beginning of a
Megayacht design. In this respect, RENK understands its
job most creative and challenging.
Beside principle arrangements of the prime movers in most
cramped engine rooms, RENK specialists also support
the client concerning the selection of the various types of
couplings, mounts, and line shaft bearings in a propulsion
train. To minimize the transmission of noise and vibrations
via the steel structure of the foundation or the shaft line,
the most effective arrangement of single or double elastic
mounts to the gear box is elaborated and recommended
by RENK.
Finally, the combination of ingenious light weight, tuned
with low noise and vibration requirements forms the
ultimate solution for the Megayacht.
Design Features
R
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Three dimensional gear box casing model
during design.
Scale model of a COGAG gear box
based on the design results.
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The manufacturing of every RENK gear box is permanently controlled and
checked on highest level based on our Quality Assurance Standards in
conformity with the quality management system EN ISO 9001.
The RENK strategy to comply with highest quality standards starts with
the education and steady training of our staff, and is continued by a most
demanding audit of our component suppliers.
Not only the investment in RENK’s human resources is handled thoroughly, but
to keep our production facilities on the latest stage of the art has further highest
priority. Machining and heat treatment facilities are steadily developed in order to set
alive all our theoretical knowledge in our products.
ABOUT QUALITY AND TESTS
Our high accuracy grinding facilities ensure all our knowledge about tooth
corrections and grinding quality will be put into practice. Large case carburized
gears with an outer diameter of up to 3.9 m can be finish machined with the latest
grinding technology, in order to realize the world wide highest quality standards.
During final assembly, every RENK gear box is treated according to special
assembly and testing procedures as well as RENK standards like tooth contact
pattern tests and cross checks of plain bearing seats, which have been developed
according to RENK’s extensive experience in the field.
Finally, RENK gear boxes have to undergo numerous tests and measurements at the factory
acceptance test bench before they are released to leave the plant. Measurement results are an
important input for the noise and vibration prediction which RENK can already provide in a very early
design stage for new gears.
Production
CODAD Gear
Megayacht
Power: 2 x 7,4 MW
Input speed: 1350 rpm
Output speed: 274 rpm
Weight: 31 t
Low noise CODAD
arrangement with
fluid couplings.
High accuracy grinding
technology, 3,9 diameter
Quality up to ISO 1.
Case hardening up
to 3,2 m diameter.
Assembly of a COGAG gear 2 x
5.400 kW at 12.000rpm/680rpm.
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Research and Development
RENK puts a high demand on its own products and
the requirements are growing steadily. Furthermore,
the request for highly flexible propulsion concepts
leads to more and more complex propulsion systems.
For RENK as the world leader in designing and
manufacturing of highly sophisticated gear box
plants it is essential to continuously increase the
technical expertise based on our own research and
development programs.
It is important for RENK that in the course of regular
conversations with our clients we get knowledge of
their changing demands. A mayor element of the
RENK philosophy is to incorporate this feedback
from the operator as an important input for our
research and development activities.
The final target is to use the knowledge and results
of our R&D activities to improve performance and
reliability, keep up with highest technical standards
and make use of them for an even advanced design
and manufacturing.
One of the main R&D topics is to reduce the noise
and vibration excitation of the gear mesh, by
optimum choice of the geometry parameters of the
gear teeth.
For instance, RENK spent a lot of research and
development efforts and gathered significant
knowledge with the complex system of mechanical
links in the systems where undesirable noise and
vibrations within the propulsion plants find their way
into the ships structure. This knowledge, together
with the well experienced RENK single hard and
double hard elastic mounts results in best noise
performance on board of Megayachts and Navy
vessels.
RENK makes use of its long lasting relationship with
internationally renowned research institutes. Results
out of this high level research projects directly find
their way into our products to the benefit of our
clients.
Close connections to our partners like engine manufacturers and ship
yards, and a steady exchange of experience together with them finally
ensures that RENK uses any opportunity to satisfy the increasing demands
of its clients.
One of the main R&D topics is to reduce the noise and vibration excitation
of the gear mesh, by optimum choice of the geometry parameters of the
gear teeth.
High efficiency single
hard elastic mount.
Touch screens as part of individual developed
monitoring systems.
CODAD arrangement 2 x 4.320 kW at 1.800rpm /
275 rpm, single hard elastic
mounted on test bench.
RENK’s low noise double helical gear in the test laboratory at Design Unit, UK.
Comparison on
different noise speci-
fications.
ASL 88 / 92 single stage
gear during noise measure-
ments.
single hard
elastic mounts
rigid mounts
double hard
elastic mounts
Frequency [Hz]
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d
a
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[
d
B
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Transfer of engine T/V to
gear box foundation
Frequency [Hz]
T
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[
m
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/
N
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]
Input tourque
Output tourque
Input tourque
Output tourque
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References
Decades of RENK’s experience in development, design
and manufacturing of special purpose marine gear
units on highest quality levels provide the solid basis
for gas turbine and diesel engine driven propulsion
systems for individual Megayachts throughout the
whole world.
BUS 225, 17 MW
Rising Sun ASL 110, ASL 114
Carinthia VII
Destriero, with 3 x BUS 225
Golden Odyssey
ECO with 1 x BS 80 and 2 x AOS 50
Carida with SWUF 40, 1972
For details, please refer to the separate
reference list.
Ultra light weight aluminum gear box casing for a
COGAG arrangement during assembly.
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RENK Aktiengesellschaft • Gögginger Str. 73 • 86159 Augsburg, Germany
Phone: +49.821.5700.627 • Fax: +49.821.5700.595 • E-Mail:marine.augsburg@renk.biz
www.renk.eu
Innovative Gear Solutions in Naval Propulsion Systems
BUS 2 x 122,
Ultra light weight aluminum gear box casing
for a COGAG arrangement during assembly.
Thrust bearing that isolates structure-borne sound for Megayacht.
By means of integrated elastomer elements this thrust bearing isolates.
The structure-borne sound to prevent a transmission to the thrust shaft,
the bearing casing and further on to the ship’s foundation. Moreover, it
is able to compensate for a radial offset of +/- 3 mm and thanks to an
integrated hydraulic system even for an angular offset of +/- 0,1°. It
even offers a propeller thrust measurement.