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The geometrical tolerances of the SSS At the cold mass construction ( ACCEL) and after cold test of the cryo magnets (CERN WP18) M. Bajko AT MAS 22nd of Nov. 2005. Content. Tolerances side by side Conflicts Summary of the tolerance table. Length. ACCEL 4126±0.9. ACCEL 64±0.5.
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The geometrical tolerances of the SSS At the cold mass construction ( ACCEL) and after cold test of the cryo magnets (CERN WP18) M. Bajko AT MAS 22nd of Nov. 2005 Content • Tolerances side by side • Conflicts • Summary of the tolerance table
Length ACCEL4126±0.9 ACCEL64±0.5 ACCEL1463±0.8 Not measurable 1220±0.7 Not measurable CERN55891.7 CERN64±0.5 V line extremity 242±0.1 BPM support
BPM Upstream side RACCEL= 0.2 mm RCERN= 0.5 mm ACCEL= 0.1 ( 1mrad) CERN= 0.1 ( 1mrad)
V lines Downstream side ACCEL= 0.3 mm ( 4 mrad) CERN= 0.33 mm ( 4. 5mrad) LACCEL= ±0.5 mm LCERN= ±0.5 mm RACCEL= 0.6 mm RCERN= 0.87 mm ACCELmax=CERNmax = 73.25 mm ACCELmin=73.45 mm CERNmin = 73.4999 mm
Service lines (Upstream RACCEL= 1 mm RCERN= 1.6 mm
Service lines (Downstream Measuring surface Measuring surface RACCEL= 1 mm RCERN= 1.6 mm RACCEL= 1 mm RCERN= 1.6 mm
Shape Tolerances RCERN= 0.87 mm g= 0.5 mm r= 0.65 mm CBT flange on downstream side
CONFLICTS ? No margin for Transport, cold test, cryostating, change of reference frame The shape of the cold bore locally at the end is to be better positioned than the cold bore flange g= 0.5 mm r= 0.65 mm R = 0.87 mm CBT flange on downstream side ACCEL= 0.1 ( 1mrad) CERN= 0.1 ( 1mrad)
SUMMARY All tolerances at ACCEL are given in the 12 plug co-ordinate system, while at WP18 at CERN is given in the GA co-ordinate system 1. The Radial tolerance of V1&V2 on the Connection at WP18 are relaxed values as offered by VAC, thank to experiment gained with BPM/beam-screen/drift tube installation. A ‘grey area’ (up to 0.8mm) can be accepted with some caution, see minutes WGA72. 2. If the tolerance is exceeded, the angle w.r.t. the local axes of the cold bore tube shall be measured and checked with the same tolerance. Nominal length to be changed with +2 mm. ECR by MM Aperture tolerances at WP18 : race-track area, see figure below Connection side : g = 0.5 mm, r = 0.6 mm Lyra side : g = 0.5 mm, r = 0.65 mm A) In case of non-conformity for aperture, a shift or rotation is applied to the whole assembly at installation in order to close it.
Thanks In the name of B. Jeanneret, M. Modenaand myself for the constructive collaboration of • VAC in particular to G. Schneider, R. Veness and P.Leupele • MAS in particular to K. M. Schirm • CRI in particular to J. P.Tock and C. Garion • SU in particular to P. Winkes and D. Missiaen • MEL in particular to H. Prin
Length 1463±0.8 64±0.5 4126±0.9 No reference , not measured 1462±0.8 4189±1.4 ACCEL 64±0.5 2420.1 4125±0.9 1220±0.7 55871.7 640.5 CERN No reference , not measured 55891.7 64±0.5
Impact of the over length on the NESTED BELLOW 20 % of the magnets are longer then nominal with 2.5 mm Tolerance - 2.5 mm Fix point of the beam screen Quadratically - 2.4 mm CBT Beam screen SSS nested bellow BPM Linearly summed the tolerances + 2.2 mm Tolerance of 1 mm, so min -1 mm 34 % of the magnets are 2.2 mm longer then nominal The max. value is 3.6 mm.