bil chamber equipment status wires gas leak test results and gas distribution related items analysis...
TRANSCRIPT
• BIL Chamber Equipment Status
• Wires
• Gas Leak Test Results and Gas Distribution Related Items
• Analysis and Results from the Cosmic-Ray Test Stand
Mauro Iodice - MDT Italia - Pavia, 30 Settembre, 1 Ottobre 2002
26 sett. 2002
FILI ROTTI FILI ROTTI Gas Bar Gas Bar Gas Bar Gas Bar LUOGO Perdita TOMO
lato RO MLO lato RO MLI latoROMLO latoROMLI latoHVMLO latoHVMLI
RM-001 BIL2A01 1 l̂ayer:2 ,̂22 d̂a sx 4 l̂ayer:12 d̂a sx S6R0022 S6L0019 S6L0023 S6R0024 ROMA3 2 mbar/d si
RM-002 BIL4A01 nessuno nessuno ROMA3
RM-003 BIL6A01 nessuno 3 l̂ayer:36 d̂a dx S6R0016 S6L0015 S6L0017 S6L0018 CERN 1.4 mbar/d
RM-004 BIL2A05 nessuno nessuno P6R0014 P6L0013 P6L0011 P6R0012 CERN 0.3 mbar/d si
RM-005 nessuno nessuno CERN* si
RM-006 BIL4A05 nessuno nessuno P6R0010 P6L0007 P6L0009 P6R0008 ROMA3 2 mbar/d
RM-007 BIL6A05 nessuno nessuno ROMA3 si
RM-008 BIL2A09 nessuno nessuno S6R0030 S6L0026 S6L0028 S6R0020 ROMA3 7 mbar/day si
RM-009 BIL4A09 nessuno nessuno ROMA3
RM-010 CERN
RM-011RM-012 BIL4C01 nessuno nessuno S6L0041 S6R0033 S6R0034 S6L0043 ROMA3 1ML OK
RM-013 BIL6C01 2 l̂ayer:36 ;̂4 l̂ayer:20^ 4 l̂ayer:5 ̂da sx S6L0031 S6R0029 S6R0027 S6L0032 ROMA3 <1 mbar/d
RM-014 BIL2C05 nessuno 1 l̂ayer:8 ;̂3 l̂ayer:36^ ROMA3
RM-015 BIL3C05 3 l̂ayer:32 d̂a sx nessuno ROMA3
Chamber Equipment and gas leak test Status :
15 BIL Chambers (side A sectors 01, 05, 09 - side C sectors 01, 05)
received from Roma1, out of 19 built so far.
Al 6 Settembre 2002
Wires :
RM-012
RM-014
RM-015
6 Sett.2002 27 Sett.2002
Vista lato HVFilo sfilato lato HV
Filo sfilato lato RO (tube bar-code side)
( RM-013 3 fili rotti - stabile )
Chamber Suddenly Starts to Leak !!!
Gas Leak Test Results :
Back to Normal (0.6 mbar/day) after connector plate substitution
BIL4A05 Gas Leak Test
BIL2A05 Gas Leak Test
• Test gas bar OK
• Montaggio su camera ...
• Test Multilayer …. KO !!!
• Perdite dal gas connector (half jumper)
• Sempre in tubetti 3o o 4o Layer
Gas Leak Test Recent results
The gas distribution system …Freiburg investigation !
FAILURE RATE :
Failure/ML ~ 6
6 tubi /48 tubi_totali = 12 %
6 tubi /24 tubi_3o-4o Layer = 25 % !!!
8 “Gruppi” assemblati con perdite evidenti mandati a
Friburgo (Gregor) per “analisi”
Leak
From: Gregor Herten <[email protected]>To: Mauro Iodice <[email protected]>Cc: Gregor Herten <[email protected]>, "Mohr, Wolfgang" <[email protected]>, Ulrich Landgraf <[email protected]>, Filippo Ceradini <[email protected]>, [email protected], Agostino Lanza <[email protected]>Subject: Re: gas leak problems
Dear Mauro,
we have received your 8 tubelets and have checked them.
4 have problems in the assembly (black piece not mounted correctly, O-ring squeezed)
4 have problems with the tubelets. There are cracks in the tubelets near the bulge region.
This is exactly the same problems as the US tubelets.
Unfortunately this means that the tubelet problem exists also for the barrel.
My impression is now that we should abandon brass tubelets.
This is expensive but everything else is too risky.
I shall follow this up and inform the collaboration.
The gas distribution system …Problems !
The gas distribution system …Problems !
CRACKS
Subject: Re: gas leak problems
Mauro,
it is always difficult to find the real reason of a leak after one disassembles the
pieces. All we can say is that 4 tubelets had cracks and the other 4 were o.k.
For these 4 we found that the black piece was not fixed correctly on the bulge.
When you use the assembly tool one should hear a click when the black piece snaps onto the bulge.
For the other 3 we had the impression that the O-rings were tilted.
1) use a lot of alcohol to make sure that the O-rings slide well
2) push the O-rings fully against the black plastic piece (this avoid sliding of O-rings.
……
Gregor
The gas distribution system …Problems !
Questo significa che anche il montaggio non e’ “FAIL PROOF” ?
The gas distribution system
New GAS-bar holes profile :
Sharp edge damage o-rings
“The OLD problem”
4.4 1.15 4.71.7
Rounded corner
SOLUTION 1Roma
SOLUTION 2Pavia
Gas Distribution System - Come procediamo ?
Scenario n. 1 : Procediamo con annealing dei tubi esistenti e andiamo avanti.In parallelo: procurement altri tubi (acciaio ?) - Test
Scenario n. 2 : Fermiamo l’equipaggiamento delle camere (la costruzione no (?))fino alla disponibilita’ di tubetti piu’ affidabili.
Pros :La produzione va avanti.Viene ulteriormente testato il “montaggio” (HALF JUMPER) e verificata la cura anti-cricche
Cons : La produzione si ferma per MOLTI MESI.Alla ripresa dei lavori …come andra’ il montaggio ? (HALF JUMPER)
Pros : Non si spreca lavoro!Ci si puo’ concentrare in studi di sistemi di distribuzione “alternativi” ?
Cons : Rischiamo di dover riequipaggiare tutte le camere gia’ montate con un sistema nuovo
Cosmic Rays data - tube resolution
reso
luti
on
(m
m)
(Resolution dominated by multiple scattering)
RPC1
RPC2RPC3
RPC hodoscopeequipped with 3 MDT chambers
Tube maps and Timing spectra analysis
Tube maps for chamber BIL4A05 MultiLayer 2
Timing spectra formezzanine 3 1st layer
Total Drift Time distributions
chamberBIL4A05 MultiLayer 1 chamberBIL4A05 MultiLayer 2
Alignement studies with cosmics
x
b(mm)
Wire length coordinate
“TOMOGRAFIA” delle camere con tracciamento sotto raggi cosmici
b
xWire length coordinate
MultiLayer up
MultiLayer down
Large x tracksmall x track
Effetto di una rotazione relativa fra i due MultiLayer
z
y
y
z
Alignement studies with cosmics
“TOMOGRAFIA” delle camere con tracciamento sotto raggi cosmici
Risultato di analisi blindda simulazione (A.de Salvo)
La rotazione di un multilayer rispetto all’altro e’ in accordocon l’osservazione qui riportata???????????????????
WORK in
Pro
gress
b (m)
xWire length coordinate
Gas bar on chamber - Faraday Cage - Meccanica Un po’ di foto
Carrelli - Meccanica - …Un po’ di foto