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University of Athens ATLAS BIS MDT assembly http://www.phys.uoa.gr/Atlas/MDT. D. Fassouliotis P. Ioannou C. Kourkoumelis V. Pancheluga D. Pappas E. Stefanidis V. Birioukov (engineer from Protvino). HEP 2001 Presented by Heraklion, 6-8 April 2001 D. Fassouliotis.
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University of Athens ATLAS BIS MDT assembly http://www.phys.uoa.gr/Atlas/MDT • D. Fassouliotis • P. Ioannou • C. Kourkoumelis • V. Pancheluga • D. Pappas • E. Stefanidis • V. Birioukov (engineer from Protvino) HEP 2001 Presented by Heraklion, 6-8 April 2001 D. Fassouliotis
Beauty Physics CP violation SM/SUSY Higgs New Vector Bosons H μμμμ B+ J/ψK+ Physics Requirements of ATLAS Muon Spectrometer • Acceptance • Efficiency • Momentum Resolution
OUR AIM: Wire/check all the Monitored Drift Tubes for the ATLAS BIS chambers 30,000 !! Tubes – 128 chambers With Construction specifications…: Wire position ± 25 μm Wire tension 350 ± 15 gr Gas leak rate < 10-8 bar*l/s at 3 bar Leak at 3.4 kV (gain 1.6*105) < 2nA/m Finished tube length 1671.50 ± 0.25 mm …necessary to achieve the physics results
TO ACCOMPLISH AIM: • Build a clean room • 20±1 oC • Class 50,000 • Develop a wiring table+wiring tools • Flat top • Tube holders • Alignment of two end-plug-holders • End-plug insertion (coaxility tube/end-plug) • Tube pressure crimping • Speed of wire threading • Wire tensioning • Develop on-line QA of tube construction • parameters • Length check • End-plug/tube axis coaxiality • Wire tension • SITE WAS CERTIFIED ON MAY 1999
Daily operational tasks • Check of air-condition system • Verification of 200 and 8 Atm pressures Actions • Calibration of mechanical tension meter • Calibration of Tube Length fixing system • Calibration of Tube length measurement system • Packing / Unpacking Tubes • Check of alignment • Tubeverification • Measure wall thickness • Visual inspection • Clean if needed • Wireverification • Visual inspection • Throw part if needed • Wiring procedure • Place tube to first position / scan bar code • Thread wire in tube • Insert wire through the endplugs • Crimp wire on the left hand side • Move to second position / respect clocking • Pass wire through right hand side tube crimper • Fix length (choosing gaps) with movable LHS crimper • Secure and Crimp tube • Perform pretension / tension • Crimp wire on the right hand sideTube is ready • End-plug assembly procedure • Visual inspection • Measure end-plug diameter • Clean all components inultrasonic bathwith 100% ethyl alcohol. • Insert twister / stopper • Insert spring • Insert/crimp copper pin • Insert O-ring • QA/QC procedure • Finished tube Length measurement • Coaxiality measurement • Wire tension measurement • Dark Current measurement
SINCE THEN • Several Improvements with the aim • Minimize failures (rejected tubes) • Increase Production Rate • Reach Production Stability • Decrease Maintenance Operations Wiring table reinforcement / expansion freedom End-Plug Preparation go/no-go gauge / copper pin crimper Wiring Tooling Wire crimpers + base / tube clamps / pressure valves QA/QC Tooling Tube length meas./ coaxiality meas. / tension meas. Automatization See E. Stefanides presentation Operational Details
Upper: View of the wiring table during Module 0 production. Lower: View of the wiring table after the reinforcement upgrade.
Go/no-go gauge Tooling for copper pin crimping on the brass sleeve.
The wire crimper holder The micrometric adjustable mount of the tube clamp
Novel wire tensionmeter in use low-cost compact reliable
Finished Tube Length Some Results Wire Tension
As a summary … • Minimize failures Dramatic decrease of accidental incidents Decrease of failures due to tolerances • Increase Production Rate 5 min /tube + 2 min end-plugs • Reach Production Stability Average of ~45 tubes /day 5800 MDTs assembled so far !!! • Decrease Maintenance Operations Finance providing Our commitments will be fulfilled