CEA - Irfu – Mois 2011 – 1 Cavity-string alignment experience in the EXFEL prototype cryomodule assembly Michel Fontaine CEA – SACLAY DSM/IRFU/SIS TTC meeting at IHEP (Beijin) 12/07/2011

CEA - Irfu – Mois 2011 – 2 Alignment based on DESY process Cavities definition Mechanical axis definition Electrical axis characterization Module constitution Cold mass adjustment Beam axis frame definition : Helium pipe axis as longitudinal axis translated vertically Vertical axis based on gravity (given by AT401 or Nivel 20 at DESY) Temporary glued points measurement Cavity string alignment (within 0.1 mm from the theorical position) Final cold mass survey Module integration Vacuum vessel adjustment Cold mass adjustment Final module survey External references coordinates are given to the alignment team Thanks to M. Schlöesser M. Noak W. Benecke

CEA - Irfu – Mois 2011 – 3 Instruments and accuracy InstrumentAccuracyUse Laser tracker AT401< 20µm String adjustment, levelling Laser tracker AT901< 20µm String adjustment, Cavities’ measurement Optical level NA320µm Cold mass level adjustment Bubble level or inclinometer 0.1mm/m or 0.02 mm/m Cold mass and vacuum vessel vertical adjustment

CEA - Irfu – Mois 2011 – 4 Software : Spatial Analyzer overview Local network measurement to locate all instruments in the same frame Measured points with T probe Geometrical ly constructed axis points (fitting a circle)

CEA - Irfu – Mois 2011 – 5 Saclay’s specific task and strategy Specific task 1.Prototypes assembly and alignment based on DESY process 2.repeat 100 times a reliable process for serial production with a contractor 3.Data transmission to DESY for alignment in tunnel Strategy 1.Uniformity on survey processes 2.Increase repeatability on measurement 3.Data storage

CEA - Irfu – Mois 2011 – 6 Uniformity 1.Dedicated software for point measurement, calculation and data management 2.Special care on machining references : 1.Boreholes on cavities flanges designed by DESY 2.Centering plates for helium pipe placed at each extremity during the integration

CEA - Irfu – Mois 2011 – 7 Data Management Cavity points and axis from DESY Measurements from instruments Calculation Result file for alignment users QC data and reports SACLAY’S dedicated software

CEA - Irfu – Mois 2011 – 8 Status  PXFEL2_2 : beginning with new trackers and software OK  Survey of cavity string support for further inspections  PXFEL3_1: faster integration ok for operator and process Coming soon…  Centering plates and dedicated software tests  Boreholes on all cavities  Extremity points on valves machined instead of glued magnetic supports

CEA - Irfu – Mois 2011 – 9 Conclusion  Excellent collaboration between Saclay and DESY alignment team  An extensive use of laser tracker with T-probe gives more possibilities to the surveyor combining topography and MMT 3D metrology  Small tracker AT401 can be used instead of optical levels because of it’s compensators quality  To be continued… Software and database management operating soon

CEA - Irfu – Mois 2011 – 10 Discussion items 1.Tolerances 2.Facility 1.Temperature 2.air flow into the measurement hall 3.Mechanical design 1.Special care on machining measured points 2.Centering tools for repeatable measurement 4.Avoid invasive structure 1.Frames and shipping tools 2.Tubes and mechanical adjustment devices 3.Volume of tuning systems 4.Data storage 5.Shipping

CEA - Irfu – Mois 2011 – 11 Thank you for your attention