JEC COMPOSITES MAGAZINE - Issue #119 - Supplement lnnovation report - 21

Paris, France
March 6-7-8, 2018

Mould-less monocoque manufacturing process
MTorres developed a new manufacturing process for large composite structures with fully-integrated reinforcements in a final single part.

Initially focused on the manufacturing
of fuselages, the process offers relevant
weight savings for the final structure
due to:

The process introduces a new mouldless approach, where elementary composite components are prefabricated
and joined together to create an initial structure geometry that acts as a
mould for the external structural skin.

- The elimination of fasteners inside the
structure;
- More flexible geometry and reinforcements configuration;
- A critical reduction in the manufacturing
costs, suppressing most of the assembly
tooling needed for such a structure.

The initial structure then remains inside the final product as an additional
structural component.
This allows for a co-curing process for
both the skin and the initial components, creating a single final structure.

Finally, an out-of-autoclave manufacturing process was chosen for all the
components used: an infusion-based
production that avoids the need for
autoclave curing while using MTorres
internally-developed low-cost dry
carbon fibre tows for the automated

Finalist: M.Torres Diseños Industriales
SAU (SPAIN)

fibre placement process, even further
increasing the cost reductions for the
global component.

Full-OoA TP welded primary airframe
The airframe's skin is produced by fully-automated deposition of materials
by automated fibre placement (AFP) of
new PEKK carbon slit tape and copper
slit foil (innovative lightning strike protection material). STELIA Aerospace
developed optimized AFP process parameters for the carbon slit tape and
copper slit foil (heating laws, speed,
compaction pressure) to allow an efficient out-of-autoclave (reduced investment) thermal consolidation cycle and
ensure good material quality.
The omega stringers and frames are produced with a fast stamp forming process
with a robotic loading system well-suited to automated high-volume production. Process simulation software was
used to define the right stamping design
tools in order to quickly achieve accurate
sizing tolerance on the parts. This method makes it possible to avoid numerous
and expensive tooling adjustment steps.
This collaborative works was conducted by French subcontractors: CETIM

in Nantes for the frames, Aviacomp in
Toulouse for the stringers and Compose
for the tooling. A new 12K woven carbon/PEKK laminate was specifically developed for the stamp forming process in
order to achieve a cost-effective solution
(vs. 3K).
The automated assembly process used
for the stringers is based on robotic
dynamic induction welding. The innovation focuses on the development of
induction welding on a carbon UD tape
with a metal protection on the surface
and skin thickness variations. A test
campaign was performed with a high
number of specimens to set up the key
induction welding process parameters.
The multi-functional one-part access
door is produced by an overmoulding
process. By combining two processes:
injection (short fibre) and stamping
(continuous fibre), additional features
(inserts, ribs and hinge) were included in the access door to obtain a single
lightweight part.

Finalist: STELIA Aerospace (France)
Partners: Porcher Industries (France),
Sintex NP (France), Compose Tool
(France), CETIM (France), Aviacomp
SA (France), Institut De Soudure/
Composite Integrity (France)

N° 119 supplement - Innovation Report

/ jec composites magazine

Table of Contents for the Digital Edition of JEC COMPOSITES MAGAZINE - Issue #119 - Supplement lnnovation report