1. 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

2. 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

3. 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

4. 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

5. 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

6. 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

7. 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

8. 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

9. 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