JEC COMPOSITES MAGAZINE - Issue #92 - October/November 2014 - 63

©Felix von Canstein
© Loren Morrissey

to generally employ
the system within
our production, we
processed a very
large volume of test
panels to analyse
the laminate properties and produced
very complex
carbon fibre components to prove the
process reliability
and repeatability."
In the end, Mr. Stray
and his team mates
were impressed.
"With MTI®, the
resin flow during
Fig. 2: Carbon fiber body work - designed and manufactured by German
infusion looks after
Advanced Composites
itself. It moves until
market, the MTI® product line as well as
it hits the MTI® line and then stops. If
technical support and on-site consulting
you have a dry patch, there is only one
services. So far, the most prominent U.S.
way for the resin to go, and the vacuum
client is the Miss Geico offshore racing
keeps pulling until the resin has permeateam. In addition to his job as crew chief,
ted everything." Analysis of cross-sectioGary Stray is working on a revolutionary
ned, finished laminates showed that the
new construction for an offshore racing
parts have a void content on a par with
boat. He explains that the current Miss
components manufactured with an autoGeico race boat is powered by twin
clave process. The parts also impressed
1,750-hp engines weighing 680.4 kg
the team with a perfect surface quality,
each. Capable of 322 km/h in flat seas,
where in the past a lot of post-cure
they frequently face 1.2m waves, endufinishing was required. After winning
ring continuous 4G to 12G impact loads.
their 7th world champion title in 2013,
He adds, "We have been working with
the team made plans to infuse an entire
German Advanced Composites since
boat in late 2014.
March 2013, shortly after they launched
the MTI® system for the first time on the
Added value
American market. But before we decided
But what distinguishes the MTI® system

Fig. 3: Miss Geico`s composite structure has to cope with up to 12G impact load

from the standard vacuum infusion
system? MTI® stands for Membrane
Tube Infusion and is based on a semipermeable membrane hose which is
used for evacuation and supports air and
gases to be drawn out of the system while
ensuring that the infused matrix material
stays inside the mould cavity. The design
of the MTI® hose is further characterized
by an integrated spiral wrap that keeps
the cross section open for maximum
evacuation performance, even under the
pressure force of the compacted infusion
set up, and a high-tech textile compound
consisting of 3 different components: 1)
a non-woven fabric protecting the membrane from the inside that improves the
airflow and enhances the flexibility of the
hose; 2) a woven fabric that ensures the
tensile strength and improves handling,
and finally 3) the membrane, which was
optimized to support maximum airflow
but needs to ensure a reliable resin
barrier. Furthermore, it provides a highquality tactile feature that protects the
vacuum film against damage and ensures
pleasant working conditions using the
MTI® hose.
Other styles of break zones (e.g. peel ply
wrapped vacuum line) will eventually
wet out so that resin will be drawn out of
the laminate. This will not happen with
the MTI® hose. Even with a thin, slowcuring resin system, the membrane hose
forms an absolute barrier between the
resin hydraulic pressure and the low pressure of the vent tube, even after the resin
reaches the MTI® hose, thus creating the
perfect environment to produce voidfree laminates. The fact that the resin
catch container can get an early retirement is only one obvious advantage. This
way, manufacturers of extremely large
composite products such as wind turbine
blades or offshore yachts achieve cost
cutting effects by eliminating the catch
container management and reducing
resin consumption. However, the closed
hydraulic system offers additional, more
decisive advantages. The hydrostatic
laws make it possible to easily control
the process, particularly in regard to flow

No92 October - November 2014

/ jec composites magazine 63
JEC COMPOSITES MAGAZINE - Issue #92 - October/November 2014

Table of Contents for the Digital Edition of JEC COMPOSITES MAGAZINE - Issue #92 - October/November 2014
