THE VACUUM BOX FOR COMPASS CRYOSTAT

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THE VACUUM BOX FOR COMPASS CRYOSTAT

1. MECHANICS OVERWIEV
2. WINDOWS
3. INTEGRATION WITH HODOSCOPE

G. GIRAUDO I.N.F.N. TORINO
MUNICH 23/10/2007
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MECHANICS - OVERWIEV
G. GIRAUDO I.N.F.N. TORINO
MUNICH 23/10/2007
3
MECHANICS - OVERWIEV
The First Cone holds the first detectors support,
is made out of aluminium alloy and contains the
gaskets (O-ring) housing. Mass 1.8 kg
The intermediate cone holds the connectors
flanges, is made out of aluminium alloy. Mass
7.24 kg.
G. GIRAUDO I.N.F.N. TORINO
MUNICH 23/10/2007
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MECHANICS - OVERWIEV
The final cone holds the second detectors
support, the vacuum pipes-flanges and the
suspension wings. All parts are made out of
stainless steel (AISI 304) Due to the dimensions,
two special gaskets should be made. Mass 10
kg. Total mass of vacuum box 21 - 22 kg
G. GIRAUDO I.N.F.N. TORINO
MUNICH 23/10/2007
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WINDOWS
Four type of window was made and tested. Two of
them fail when stressed by the vacuum after few
seconds. One was able to withstand the stress due
to vacuum, but shows a permanents deformation
after few cycles and a big displacement in the
centre (30 mm) One was able to withstand the
stress due to vacuum, but requires a bigger
amount of material budget.
G. GIRAUDO I.N.F.N. TORINO
MUNICH 23/10/2007
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WINDOWS
FAILURE window was a sandwich of mylar foil (250
µm) carbon fibre (250 µm), glued on the flange
with epoxy resins. Failure was due to the
constraint, too flexible.
G. GIRAUDO I.N.F.N. TORINO
MUNICH 23/10/2007
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WINDOWS
FAILURE window was a mylar foil (250 µm) glued
on the flange with epoxy resins, reinforced with
44 carbon wires. Failure was due to the
constraint, the supporting surface is too small
(wall thickness is only 9 mm), no FEM simulation.
G. GIRAUDO I.N.F.N. TORINO
MUNICH 23/10/2007
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WINDOWS
NO FAILURE window was a mylar foil (250 µm)
glued on the flange with epoxy resins. Permanent
deformation appear after few cycles, displacement
in centre 30mm - FEM simulation shows 12 mm.
G. GIRAUDO I.N.F.N. TORINO
MUNICH 23/10/2007
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WINDOWS
NO FAILURE window was a sandwich of mylar foil
(250 µm), one ply of carbon fibre (125 µm), one
layer of rohacell (5 mm), one ply of carbon fibre
(125 µm) glued on the flange with epoxy resins.
Good behavior under vacuum stress, good vacuum
tightness. Simulation show a displacement in the
centre of 2.3 mm, while measurement shows a
displacement of 3.3 mm. Too much material.
G. GIRAUDO I.N.F.N. TORINO
MUNICH 23/10/2007
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WINDOWS
NEXT A new type of window is under study. The
constraint wall is 15 mm, the window is now a
foil of mylar (125 µm) glue on a support of high
modulus carbon fibre ply (M46J - 200µ). Delivery
this week. The foil is pinched between the flange
and the cone wall.
G. GIRAUDO I.N.F.N. TORINO
MUNICH 23/10/2007
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INTEGRATION
G. GIRAUDO I.N.F.N. TORINO
MUNICH 23/10/2007