28th of March 2006marta bajko, at mas for WGA 77

SSS Tolerances WGA 77

Summary: ECR on the length

Angular defect of V line flanges

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 28th of March. 2006

28th of March 2006marta bajko, at mas for WGA 77

SSS Tolerances WGA 77

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.

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

r

g 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.

Tolerance table

Nominal length to be changed with +2 mm. ECR by MM8 8 1.5

1461.25

4124.25 5585.5

28th of March 2006marta bajko, at mas for WGA 77

SSS Tolerances WGA 77

ECR on length

28th of March 2006marta bajko, at mas for WGA 77

SSS Tolerances WGA 77

Angular defect of the V line flanges on downstream side

28th of March 2006marta bajko, at mas for WGA 77

SSS Tolerances WGA 77

V lines Downstream side

V1 & V2 Lyra side Radial position of center

Ref is CM-B-plan axis for ACCEL / GA at WP18

0.6 0.87 mm

Angle to end cover plane

Ref is B-plan at ACCEL / GA at WP18

± 4 ± 4.51 mrad

Distance from end-cover

On nominal of 64 mm ± 0.5 ± 0.5 mm

Go-nogo gauge confirmed by P. L. VAC 73.45 73.499 mm Min diameter (on drawing sat ACCEL

73.44,73.75) 73.25 73.25 mm

1 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.

(see overleaf)

V1 & V2 Lyra side Radial position of center

Ref is CM-B-plan axis for ACCEL / GA at WP18

0.6 0.87 mm

Angle to end cover plane

Ref is B-plan at ACCEL / GA at WP18

± 4 ± 4.51 mrad

Distance from end-cover

On nominal of 64 mm ± 0.5 ± 0.5 mm

Go-nogo gauge confirmed by P. L. VAC 73.45 73.499 mm Min diameter (on drawing sat ACCEL

73.44,73.75) 73.25 73.25 mm

1 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.

(see overleaf)

RACCEL= 0.6 mm

RCERN= 0.87 mm

ACCEL= 0.6 mm ( 8 mrad)

CERN= 0.6 mm ( 8 mrad)

LACCEL= ±0.5 mm

LCERN= ±0.5 mm

ACCELmax=CERNmax = 73.25 mm

ACCELmin=73.45 mm

CERNmin = 73.4999 mm

28th of March 2006marta bajko, at mas for WGA 77

SSS Tolerances WGA 77

• There is one repair finished on SSS133: procedure as in dipoles: see doc. Edms 677407

• Good co-orrelation is found between ACCEL and CERN . On 154 cold masses: correlation co-efficent is 0.93. therefore the defect can be identified before the cold mass is cryostated and plane the necessary repairs. The list of cold masses to be repaired is done and given to SSS co-ordination.

• After OCT. 2005 no Nc were detected on magnet coming from from ACCEL . It was requested to do, if necessary ,repairs in Accel (1 case was reported of such repair by. K. Schirm).

ACTIONS IN AT-MAS and ACCEL