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H I G H - P E R F O R M A N C E C O M P O S I T E S
INSIDE MANUFACTURING
Step 1
The mold for the 15m/49.2-ft diameter DVA-1 dish was supplied to NRC-Canada by Janicki
Industries. It was delivered in five sections and assembled at NRC-Canada's facility in British
Columbia. The accuracy demanded of the dish required a tool that could hold tight tolerances
over a very large surface area.
Step 2
A&P; Technology's QISO triax braided carbon
fiber is layed up over the ply of glass fiber
that covers the aluminum reflective layer
of the DVA-1 primary dish. The arched,
suspended carbon fiber panel on the right
is scaffolding used by workers to access the
mold without touching the mold or plies.
Step 7
These DRC inners show the half-hemispheres of the ball-and-socket joint used to encapsulate
the metallic bolts that connect the dish to its primary support structure
Step 6
Finished DVA-1 primary dish, with dish rim,
as painting begins. The secondary dish can
be seen in the background.
curately fx mold position as the sec-
tions were assembled. "It's a somewhat
fexible mold," he explains, "so we were
then able to push up and pull down on
the surface from underneath a little bit
to adjust it."
The fully assembled mold offers a sur-
face error of less than 0.5 mm/0.02 inch,
reports Lacy. As a testament to the ac-
curacy of the fnished, molded main
refector, he adds, a laser scan of it was
compared to the CAD model, revealing a
surface error — 0.9 mm/0.04 inch — that
barely exceeded that of the mold. "You
can't get less than the mold's error, of
course," Lacy quips. "It means that there
is almost no shrinkage in the part."
The main refector measures 5.3
mm/0.21 inch thick and comprises —
from signal-facing side to back side — a
0.08-mm/0.003-inch layer of aluminum
for signal refectivity, a ply of woven
Ready for delivery
The finished, painted DVA-1 primary dish is moved out of the fabrication facility in preparation
for transport to the assembly site.
Source:
NRC-Canada
0714HPC IM_NRC-OK.indd 38 6/17/2014 10:55:38 AM