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The Assembly of ATLAS Muon chambers @NIKHEF. The NIKHEF Muon Mission Chamber assembly Assembly QA Assembly QC Summary, Status and Plans. 5m. 2m. NIKHEF Muon Mission. BOL=spacer+2x3 drift tube layers+ In-Plane alignment. Construct: 96 Barrel Outer Large (BOL) chambers
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The Assembly of ATLAS Muon chambers@NIKHEF • The NIKHEF Muon Mission • Chamber assembly • Assembly QA • Assembly QC • Summary, Status and Plans Marcel Vreeswijk (NIKHEF)
5m 2m NIKHEF Muon Mission BOL=spacer+2x3 drift tube layers+ In-Plane alignment • Construct: • 96 Barrel Outer Large (BOL) chambers • High Mechanical Precision: • 20mm RMS on wire positions • This talk: • BOL-0, BOL-1 and Serial Production West side has expansion length o 0.1m in Xras Marcel Vreeswijk (NIKHEF) s
Assembly Station • Granite table: 6m x 2.5m Situation mid 99 East Z Up Y North X • Three bare Cross-Plates are positioned on the station, carried by sphere holders • The combs which will support the tubes are also visible • In the background: wiring station, Quality Control setup(s) West side has expansion length o 0.1m in Xras Marcel Vreeswijk (NIKHEF) s
Chamber Assembly • Spacer monitored by RASAS Situation mid 2000 No Flexo In-plane lens NIKHEF Comb longbeam RASAS tower Xplate In-plane mask Frascati comb ‘Ear’ with sphere and RASAS-MASK Sphere tower with changeable block to adapt to tube layers West side has expansion length o 0.1m in Xras Marcel Vreeswijk (NIKHEF) s
Block 3 Block 2 Ypitch 26.011mm Scatter 5um Block 1 ‘RASAS’ Monitors Monitor positioning during assembly by RASAS monitor: Support ‘ear’ which holds the mask xplate Changeable blocks The RASAS tower which holds the camera and lens Measured temperatures explain (small) drift Marcel Vreeswijk (NIKHEF) s
Xplate 2.4m fixed Temperature Stability • Aluminum expands 24um/ oC/m, Granite 7um/ oC/m • Under normal conditions, temperature stable within +-0.4 oC • Test case: increase temp. by 1 oC: check RASAS monitors Free to expand monitor granite Raw: 50um Correct for AL 24um/ oC/m + Correct for granite 7um/ oC/m Marcel Vreeswijk (NIKHEF) s
Tube Placing Start with QC tubes Procedure Place tubes on combs (Re-)Measure Wire Frequency Run Final-OK program IF all tubes OK, follow placing scheme Marcel Vreeswijk (NIKHEF) s
Glu Preparation Marcel Vreeswijk (NIKHEF) s
Glu Preparation Marcel Vreeswijk (NIKHEF) s
Glu Preparation Marcel Vreeswijk (NIKHEF) s
Glu Preparation Marcel Vreeswijk (NIKHEF) s
Glu Preparation Marcel Vreeswijk (NIKHEF) s
Glu Preparation Marcel Vreeswijk (NIKHEF) s
Glu Preparation Marcel Vreeswijk (NIKHEF) s
tube tube tube tube tube Gluing (BOL-0) Tube diameter 3cm Distance 65mm 2 x glue units 2x3 glue nozzles Side rope Central rope • Tube layer 1 central ropes • Spacer glued on layer 1 • Tube layer 2 central ropes • Spacer+1 glued on layer 2 • Tube layer 3 central+side ropes • Spacer+1+2 on layer 3 • etc…. Marcel Vreeswijk (NIKHEF) s
Sagcompen-sation tower Additional weight for balance Sag Compensation Residue: order 10mm • Own weight leads to large sag of xplates • Compensate (at Bessel points) with pneumatic system • Need typical P=3bar (8 towers) to carry chamber (150kg) Marcel Vreeswijk (NIKHEF) s
Sag Compensation • Xplate sag before and after compensation Chamber up Chamber (upside) down Understood within +-10mm After sag adjustment we observe (almost) symmetric sags for chamber up and down positions-> no stress Marcel Vreeswijk (NIKHEF) s
The road to BOL-0 Marcel Vreeswijk (NIKHEF)
Gluing BOL-0 Glue: Days needed 1 Glue Spacer 1 1st layer+platforms 1 spacer on 1st 1 2nd layer+spacer 4 layers Total <10 days Marcel Vreeswijk (NIKHEF) s
NW NE Global X Global Z, RASAS X SW SE Gluing BOL-0 • RASAS monitors Global Z • Relatively large Z movement layer 6 (spacer floats on glue?) Lever arm in stacking block Global Y (up) • Stability in Y appears good Marcel Vreeswijk (NIKHEF) s
Start glue Start glue Gluing BOL-0 • Guido laser test indicate tube heights in combs <10um. • Stability Xplates during gluing Layer 1 Yrasnik=2 x Sag Layer 1: dSag=7um Layer 2 Start glue Layer 3 Layer 2: dSag=10um • The sag of the xplates in layer 1 and 2 change in time. Glue crimp? Temperature? • Layer 3,4,5,6: Sag stable Marcel Vreeswijk (NIKHEF) s
The BOL-0 • The BOL-0 was mechanically • finished Dec 5th 2000 • Next, studies: • X-ray scan Marcel Vreeswijk (NIKHEF) s
The road to BOL-0 Marcel Vreeswijk (NIKHEF)
The road to BOL-1 • From 1st tube layer to 6th tube layer took 14 days (spacer not counted) • With optimal/parallel preparation the present scheme would allow a 7 day production cycle • Infrastructure and manpower-> • 10 working-days/chamber Marcel Vreeswijk (NIKHEF)
Test @CERN inTomograph Marcel Vreeswijk (NIKHEF) s
Test @CERN inTomograph Analysis of Martin Woudstra Wire positions RMS 16mm Marcel Vreeswijk (NIKHEF) s
Test stand DATCHA Like cosmic ray setup at CERN (shutdown in 2000) Test of alignment principle with prototype muon sector, using cosmic tracks --> 10mm on sagitta Marcel Vreeswijk (NIKHEF) s
Test stand @NIKHEF • Tests five chambers using cosmic rays (end 2001) • Checks wire positions • Checks DCS + DAQ Trigger modules, consisting of 50cm iron, with two layers scintillator. Ecut>1GeV Expected rate: 100Hz Marcel Vreeswijk (NIKHEF) s
Xplate 50um 400um Yrasnik= 2 x sag Chamber sag Xplate sag BOL-0 Heat Studies (No flexoos in BOL-0) The BOL-0 was covered with heat blankets, producing 50W/m2 Inplane Yrasnik= 2 x sag Gradient between MLs: 2.5 to 4 oC Sag of Chamber: 200um 50 to 80 um/oC= acceptable Sag of xplate: 25um 6 to 10 um/oC = acceptable Marcel Vreeswijk (NIKHEF) s
Status and Plans • Finished BOL-0 at NIKHEF (dec. 5th 2000) with high mechanical precision (16mm RMS) • Quality Control automated • Production of tubes started May 2001 • Now: Produce first chamber • Expect to finalize 10 chambers by end 2001 • Produce 1chamber/2weeks: 24 chambers/year -> finish summer 2005 • Late 2002, evaluate need to speed up chamber production (work weekends and/or two gluing steps/day) • Cosmic ray setup operational end 2001 Marcel Vreeswijk (NIKHEF)
RASNIK • Components provided by NIKHEF Image sensor Light source + mask Lens + holder Marcel Vreeswijk (NIKHEF) s
Precision Mechanics • intrinsic accuracy better than 10um • Positioning combs and sphere holders • Tools: • Laser + optics (straightness combs), • silicon sensor (to line up combs), • Slof (height-meter), • tilt-meters (check Torque), • Balmonitor (dZ between multilayers) The quantities which affect the wire positions are checked and found to be precise within 10um Granite table has sag of 25um + 10um light on/off West side has expansion length o 0.1m in Xras Marcel Vreeswijk (NIKHEF) s
Assembly Station • The Balmonitor is a Cross-Plate equipped with lenses. Each lens is combined with a ‘fork’ on the combs to form a RASNIK system • The Balmonitor measures the Z and Y difference between Sphere tower and Comb between North and South. (Z difference between Multilayers) • Additionally the Balmonitor is used to check for height difference between sphere towers at the reference and non-reference side (West/East) West side has expansion length o 0.1m in Xras Marcel Vreeswijk (NIKHEF) s
tube Gluing BOL-0 • Result for side (106) and central (103) ropes Central rope Central rope Central rope Central rope Central rope, sometimes bad (stability glue unit?) Marcel Vreeswijk (NIKHEF)