MSCB(MS) inter-axis in SSS Study on 32 SSS of MS magnetic inter-axis and MSCB mechanical inter-axis from measurement made after cold test (WP18). Acknowledgments Bernard Jeanneret, Arnaud Devred, Jean-Pierre Koutchouk, Mikko Karppinen, Elena Wildner 25-MAY-2005 Jerome Beauquis AT-MAS

What is the situation now? (1/2) Magnetic inter-axis out of tolerance Spread larger for magnetic (+/- 1.5 mm) than for mechanical (+/- 1 mm). 25-MAY-2005 Jerome Beauquis AT-MAS

What is the situation now? (2/2) 1 For mechanical and magnetic measurement : - quadrant 2 and 4 are mainly filled => inter-axis too large or too small. - quadrant 1 and 3 are not much populated => inter-axis well centered. 3 4 2 1 3 4 Ap1 Ap2 25-MAY-2005 Jerome Beauquis AT-MAS

MS correlation mech vs. mag Good correlation but correlation factor different of 1 (around 2) between magnetic and mechanic 25-MAY-2005 Jerome Beauquis AT-MAS

Mechanical vs magnetic the factor 2 found for MS may indicate an error in the feed down calculation. For others magnets in SSS, the same (or nearly) factor is found the previous hypothesis is not checked It comes from an inversion of sign in the software measurement (see talk of Juan). 25-MAY-2005 Jerome Beauquis AT-MAS

MS/MSCB --- GEO/AC mole only few points (1 to 6) measured on the MS MS represent 1/3 of the total length of MSCB assembly. Study on the MSCB good correlation => no artifact from system measurement for mechanical measurement good correlation => MS and MCB well aligned one respect to the other one 25-MAY-2005 Jerome Beauquis AT-MAS

Flanges & MQ inter-axis NO correlation between MSCB inter-axis and arounding elements (flanges and MQ) Spread much larger (3 to 4 times more) for MSCB than for MQ or flanges. Cold bore tube movement along the SSS. 25-MAY-2005 Jerome Beauquis AT-MAS

Inter-axis comparison   mean rms Ap1 Ap2 MSCB 0.003 0.004 0.203 0.213 MQ -0.039 -0.050 0.082 0.107 MO/MQT/MQS -0.009 0.110 0.139 0.186 flanges 0.048 0.047 0.216 0.188 BPM support -0.129 -0.033 0.172 0.193 25-MAY-2005 Jerome Beauquis AT-MAS

Jerome Beauquis AT-MAS Conclusions Magnetic measurement have to be rejected. Database have to be updated Id Cards and/or slot allocation update ? Mechanical measurement also? Final tolerance after MSCB assembly completion for transversal misalignment for 1 aperture is 0.23 mm. Most (all?) of MSCB’s module are in tolerance after assembly in Tesla. Cold bore tube movement : What are tolerances on CBT undulation? Deformation of CBT during his insertion in SSS? Other issue : study of location of maximum delta X along SSS axis. 25-MAY-2005 Jerome Beauquis AT-MAS