Germany) HP-RTM injection units. Preforms are robotically
placed in steel molds in the Schuler presses, followed by mold clo-
sure and resin injection. (Te Landshut facility has three Shuler
presses and six Krauss-Mafei HP-RTM injection units).
Te resin matrix is Huntsman Advanced Materials' (Te
Woodlands, Texas and Basel, Switzerland) Araldite LY 3585 epoxy
with Hardener XB 3458. It's injected, says Koschkar, at more than
40 bar/580 psi. Huntsman says the epoxy can be cured in as few as
fve minutes at 100°C/212°F. Koschkar would not reveal the actual
cure time BMW has achieved except to say that it is "less than
10 minutes" and enables BMW to meet its rate production
requirements.
Koschkar also told CT that BMW is comfortable with the pre-
forming and RTM process it has in place, noting, "we have 10
years of experience with the M-series roof." Tis is a reference to
BMW's M-series car, which ofers a carbon fber roof made via
RTM. And, he adds, "We have fewer problems with dimensions
with our carbon fber parts than we do with sheet metal."
Tat said, Koschkar admits that BMW is constantly looking for
opportunities to improve materials and process. "Our biggest chal-
lenge with RTM is curing of the part — flling the part without dry
spots," he notes. Outside of RTM, he says, "our big challenge is how
to reduce our scrap. We are always looking at ways to save material."
Tis has led BMW to assess increased use of glass fber instead of
carbon fber in some parts of preforms where material is sacrifced.
Te company is also looking at ways to reduce resin use via more
The Life Module Body Shop features 173 ABB 6-axis robots, each working
in cordoned-off cells. Employees only touch parts to move them from cell
to cell, delivering them on specialized racks through cell doors that
segregate man and machine.
This view of the i3
CFRP Building from its
mezzanine shows one of
Leipzig's three Fill
Preformliner presses
(foreground). Behind it
are the seven Schuler
presses, each equipped
with two Krauss-Maffei
resin transfer molding
injection units.
Source
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BMW
AG
Source
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BMW
AG
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