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Activities on the triplets at CERN. Reception and Acceptance Triplet String Assembly in Building 181 Handling and Transport Preparation for Installation Tests carried out in the tunnel Repairs Present Status. Reception and Acceptance. Acceptance tests to be performed following shipment:
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Activities on the triplets at CERN • Reception and Acceptance • Triplet String Assembly in Building 181 • Handling and Transport • Preparation for Installation • Tests carried out in the tunnel • Repairs • Present Status
Reception and Acceptance • Acceptance tests to be performed following shipment: • Q1: Acceptance Plan for LQXALHC-LQX-TP-0002 • Q2: Acceptance Plan for LQXBLHC-LQX-TP-0001 • Q3: Acceptance Plan for LQXCLHC-LQX-TP-0003 • DFBX: Acceptance Plan for Inner Triplet Distribution FeedboxesLHC-DFBX-ES-0001 • D1: Acceptance Plan for Beam Separation Dipoles LBX LHC-MBX-ES-0003 • Tests to be perform at CERN according to these documents • Physical inspection • Mechanical measurements • Electrical measurements • Coil resistance • Quench protection heater resistance • Coil inductance • Insulation resistance • Leakage current measurements • Thermometer resistance • Warm-up heater resistance
Reception and AcceptancePhysical inspection in Building 181 • Visual inspection of containers and shockwatches fasten on it • Removal of the container and inspection of the transport restraints • Transport data recorder return to sender for analysis • Removal of transport restraints and “spider” inspection
Reception and AcceptanceElectrical measurements in Building 181 • Electrical checks and measurements • Coil resistance • Quench protection heater resistance • Coil inductance • Insulation resistance • Leakage current measurements • Thermometer resistance • Warm-up heater resistance • Continuity of leads, busses and instrumentation for the DFBX • Polarity checks using a rotating mole • Leak checks on the internal pipes of the DFBX
Reception and AcceptanceGeometrical measurements in Building 181 • Alignment stability • Cold mass length • Cryostat length • Cartography of the tubes at the cold mass ends • Cold mass horizontal and vertical shapes • Position of the cold mass within the cryostat • Comparison with FNAL data OR • Fiducialisation • Same as above with different measurement methods • Geo Mole + AC Mole measurements to increase the accuracy on the magnetic axis determination
Triplet String in Building 181 String assembled in April 2005 with the collaboration of FNAL, AT/CRI, AT/MEL, AT/VAC, TS/IC, TS/SU • Check availability of components and tooling • Assemble interconnects, check tooling and procedures • Perform instrumentation and continuity checks for the string from DFBX • Mount and check alignment equipment • Check string behaviour under insulation vacuum • Check handling equipment
Triplet String in Building 181 What was learned: • Validation of most components and tooling for the interconnections • Demonstration of interconnect procedures in conditions close to the ones in the tunnel • Polarity of magnets confirmed in the string • Instrumentation and continuity from DFBX confirmed • Alignment of magnets under vacuum confirmed • Limited rigidity of the jacks and their supports Actions: • Some tools and components had to be improved • Procedures were refined • BPMS signal cables redesign due to interference with Q2 thermal shield • Thermal shield of DFBX/D1 interconnection had to be modified • A software bug corrected in survey applications
Handling and Transport Cold mass displacements within the cryostat during transport from the US To CERN 3 assemblies were broken during transport probably due shocks between wagons as they were shipped by train : Q3R8 cold mass has moved by ~3mm during transport to the tunnel without any shocklog alarm
Preparation for Installation • Mechanical preparation to put the different interfaces in conformity • Thermal shield modification of the D1 • Flange replacement to remove NCs (D1 and DFBX) • Preparation in Smi2 • Cold bore cleaning • Beam screen insertion • Pick up connection • Cold warm transition assembly • Thermal shield closing • MLI insulation • O-Ring seals installation • Vacuum vessel closing • Bearing pieces fixation • Preparation of the DFBX in 181 • Electrical instrumentation preparation • Frames assembly and instrumentation box • Warm gas recovery line assembly and vacuum test • Control valves installation on each line • Differential pressure valves installation
Tests carried out in the tunnel • Vacuum tests in L8 (22 Sept. 06) and R8 (17 Nov. 06) Monitoring the various displacement of the assemblies and supporting system under insulation vacuum Result: OK Go ahead with the pressure test
Tests carried out in the tunnel • Pressure test in L8 • Guarantee the inner triplet piping mechanical stability under He pressure at warm Result: Test interrupted at 12 bars by X line buckling Cause of rupture: brazed joints anneals the extremities of the tubes • All the exchanger tubes in Q1, Q2, Q3 have to be replaced • Pressure test L5 after repair to qualify X line replacement and the complete design
Tests carried out in the tunnel • Pressure test in L5 (27 march 2007) Guarantee the inner triplet piping mechanical stability under pressure Validate the new X line along the triplet (copper corrugated tube + interconnections) Monitor the H pieces displacement under pressure Result: Test interrupted at 20 bars when the support system broke and M1 bellows ruptured Cause of rupture: axial movement of Q1 cold mass towards the IP • The heat exchanger circuit remained leak tight even after the cold masses displacement • X line replacement on the other triplets continue as planed • The cold mass support system of all Q1 and Q3 has to be reinforced
Repairs “Spiders” replacement on the 3 assemblies that were broken during shipment to CERN • Removal from the vacuum vessel • MLI and thermal shield removal • “Spider” exchange (3/4) or repair (1/4) • Cold mass recryostating • Leak test of pipes that were cut to remove the spiders
Repairs X tube removal and installation of new tubes • Removal of the heat exchanger tube • Removing the vacuum vessel dome in front of Q1 • Cutting fix point between L and X lines on Q1 and Q3 • L line extremities cutting • Extracting the copper corrugated tube • Installation of the new heat exchanger tube • Replacement of L line flanges and M4 line bellow • Insertion of the new copper corrugated tube • Welding fix points at the extremities • Interconnection of the X, L and M4 circuits (see C. Garion’s presentation) • Installation of the “H” pieces • Welding X line • Leak test of the exchanger circuit from the Q1 to Q3 • Welding M4 and L lines • Leak test on the cold mass circuit