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From Bare Chambersto
Installable Chambers
Muon Barrel Week Bologna
April 11th 2003
Alberto Benvenuti
INFN Bologna
Bare Chambers (August 2002), the bubbler has improved
Most Chambers are either
Plus or Minus by construction
(Wheel specific)
Once services are attached they acquire parity (Left/Right)
Complete with RPCs they are sector specific (gravity)
Installable Chamber
• Gas Circuit
• Cooling Loop
• HV cables
• Alignment and gas manifold cables
• Alignment forks and electronic boards
• Alignment Calibration
• Grounding straps
• Finished Theta SL:
Front end cables
Test pulse cables
Low Voltage cable
Slow Control cable
Cable protection (carter)
• ancillary supports on SLs
• tap holes to attach MiniCrate
• attachment to rails (balance beam and bearings)
• attach RPCs and test that all works
Hans R. March 03
• Cables and gas pipe fit in available space but check for interferences (90^ gas connector in front)
• The insertion must be done in sequence
Flat cables
Polypropylene protection 0.9mm thick
gas pipe
HV cables
All items must be available before work on HV connectors can begin
Gas Connection: flat cables protected by plastic strip, insertion sequence: flat cables, copper pipe, HV cables
• Gas pipe shape fits well
• Must be ordered ASAP, procure copper pipe (4 to 6 weeks!), identify firm to produce them, get prototype
• Dimensions must be checked wrt present routing but present knowledge sufficient to start the procedure.
• Flat cable procurement is pending on fixing PADC position and MiniCrate position:
fix PADC position, not much freedom anyway
attach variable pigtail at MiniCrate (MB type dependent) and fix the last 6core flat cable length, find/build jumper connector.
Begin insertion of HV cables and connectors
Hans R. 021202
Gas manifolds under calibration in Aachen.
Connecting hoses to SLs are defined/approved by TIS?
Position of front manifold has been defined? Connection to PADC?
HV Cables
• 4 single ended, Beta, cables required per chamber and 2 complete, Gamma cables (Theta SL).
• Beta cables for first installation are almost completed in Legnaro (Marco + Enrico Borsato + 2 Chinese technicians). Will be shipped to CERN.
• HV test station, one set complete and under commissioning, second set to be ready early June. To be decided if first set goes to ISR or China.
• Test station to identify correct wire/pin map at soldering stage almost completed in Bologna.
• Preparatory work on connectors to speed-up soldering under way.
• Soldering stations under procurement, strict clones of the ones used in Legnaro
Aim for 2 chambers/day but rate will depend on chamber handling and available personnel
100 ready beginning of May
Baseline Cooling Loop
MiniCrate is the largest Heat source, water flows through SL front-ends before entering MiniCrate
BUT only in one side
Hans R. April 02
Tried to implement using copper pipes for but it proved too difficult.
Since cooling flow is reversed on one sector (MiniCrate to SL front-end) then cooling capacity must be sufficient independently of what heat source is first.
Choose cooling path most appropriate in view of interference of cables and MiniCrate
IP
Phi 2
Phi 1
RPC 2
RPC 1
Theta
MiniCrate
From RPC1 in Adjacent SectorIP
Phi 2
Phi 1
RPC 2
RPC 1
Theta
MiniCrate
To RPC1 in Adjacent Sector
Proposed Cooling Circuit
Cooling Connection to MiniCrate at opposite end from Theta SL front-end cables
MiniCrate can be positioned close to Theta SL FE
Cooling from adjacent sector (RPC1 =>MiniCrate => Phi1 connections)
Cooling from adjacent sector (Phi1=>Theta => Phi2 connections)
Cooling from manifold (RPC2=> Theta => Phi2 connections)
Cooling from manifold (Phi1=>MiniC=>Phi2 connections)
Cooling from manifold (Phi1=>MiniC=>Phi2 connections)
Cooling Connections
• Connections to the MiniCrate are always on the oppositeside of the Theta front end cables. This allows also to position the MiniCrate as close as possible to the Theta front end side.
• For MB1 this configuration looks like a must not an option.
•The connecting pieces are all realistic and can be improved with theappropriate tooling.
• The exercise was done without cables from the Theta SL:
signal, pulse and especially low voltage
It must be repeated with all components in place.
• Connections to and interference with the RPCs is a major worry. We should consider the use of the flexible hose for the connection DT/RPC.
• Slots instead of holes should be used on the support pieces of the MiniCrate otherwise they cannot be installed
• At least 2 x 5 different pieces in stainless steel are needed. Going from models to executive drawings is an URGENT and time consuming job.
Alignment
• Chamber handling is labor intensive and time consuming.
• Support piece is very heavy 2 people to hold plus one to put the screws
• There is not sufficient space between chambers to mount the support pieces on the stacks. 2 additional pieces (20cm) must be inserted under the chamber or move to the floor.
• An additional set is needed to streamline the operation
Chamber supports
Mounted before shipping to SX5
It requires one hour and two technicians once the pieces are pre-assembled
2 pieces
Alignment
• A significant sample of chambers (each type) should be calibrated ASAP to gain experience and verify the method.
• There is no reason why cable lengths should not be defined NOW.
• Even if cables are not available, chambers should be calibrated anyway with external cables.
• Some work is still required on the chambers:
Clean the alignment passages (NOT trivial)
Remove excess glue from reference blocks ( gas leaks?
Overpressure test again?)
Insert missing alignment pins and replace the odd ones
• Handling chambers is not easy and the logistic is painful since chambers get re-stacked. Competition for crane usage will become an issue.
• The work must be planned in advance and technical support scheduled (2 technicians).
Chambers to be installed in 2003
Torino
January – March 2004
Torino
Torino
Priority
Chamber Tests
• Acceptance (HV, OverPressure)
• Scaler (Noise), Front-End Slow Control
• Cosmic ray tests:
Must accelerate to 4 Chambers/week
Full time technical support to move chambers
More physicists to perform/analyze data
• Experts to fix HV / Front end problems
Prepare a buffer of Certified chambers
Manpower Requirements
Assuming that all pieces are on the shelf:
• Gas, Alignment PADC, HV cables, HV connectors
3 technicians (1 + 1 for soldering, 1 mechanic)
6 Chambers / week
• Cooling circuit
2 technicians
10 Chambers / week
• Cabling Front-end, Low Voltage, Protections
1 physicist + 1 technician
6 Chambers/week ????
• Tests with cosmics
Coupling to RPCs will be done as last operation
Summary
• The list of missing items is very long and still incomplete:
Front-end cables,
Test pulse cable,
Low Voltage Splitter Board
Low voltage cable for MiniCrate
Cable protections
Supports for LV splitter board, Gas manifold on MiniCrate
• At least one chamber of each type must be checked with everything on including RPCs to make sure that there will be no interferences once the chamber is installed and we try to mount the MiniCrate.
• It should not come as a surprise that Summer is approaching and our technical staff has vacation days due.