Sils ATLAS Meeting 18-9 October 2003

Mechanics for the Barrel SCT

Sils ATLAS Meeting 28-9 October 2003

Barrel SCT Mechanics - Specifications

Four stable cylindrical mechanical in carbon fibre - honeycomb sandwich (external dimensions are 568 / 710 / 854 / 996 mm diameter by 1530 mm length).

Stable to <1 ppm/°C CTE in longitudinal and circumferential directions, o –20°C < T < +30°C.

0% < RH < 50% RH at constant temperature, dimensional change in all directions, < 30 m/m.

Under stable conditions (- 10±1°C and 20±1°C in dry N2) changes in all directions, except through sandwich thickness, < 10 m/m/yr (2 point support in middle plane at both ends and 100 N/m2 uniformly distributed)

B3

Sils ATLAS Meeting 38-9 October 2003

Barrel SCT Mechanics - small parts

• Brackets and small components production.

• >40000 small pieces,

some the same for the 4 barrels, some specific to each barrel type

• The bracket shells are time consuming to produce and are on the critical path.

• Laminate by Composite Design, Machining by UNI-GE

• All components by end October

Sils ATLAS Meeting 48-9 October 2003

Barrel SCT Mechanics - barrel 6

Dirty work on Barrels before shipmentto RAL

Barrel 6 still in Geneva because of B3 delays at RAL

Counterdrilling of outer facing underneath pads Done for B6, B5 and B4, two pads to

be re-bonded on B4

Check/adjust mountability of brackets on pads, Done for B6, B5, B4

Surface preparation for bonding FSI system, Done for B6, B5, B4

Sils ATLAS Meeting 58-9 October 2003

Barrel SCT Mechanics - barrel 6

Clean Work to be done for B6,B5 and B4

• Cleaning cylinder

• Electrical continuity tests

• Mount brackets • all screws tightened with torque

controlled screwdrivers • brackets have to be electrically

isolated from cylinder

• Rough geometrical check.

• Visual inspection

B3

- penetrations through thermal enclosure designed

- support designed- tooling for support

manufacture to do- interlink design to do

Sils ATLAS Meeting 68-9 October 2003

Barrel SCT Mechanics - dry assembly

B3 + B6 B4 + B5 + B6

Sils ATLAS Meeting 78-9 October 2003

Barrel SCT Mechanics - assembly at RAL -delays!

Opto-harnesses are in production Barrel LM tape production complete Barrel-3 harnesses being evaluated ESD damage to DORIC ASIC & other production issues

(cracked lines etc)

B3 harness assembly at RAL

Sils ATLAS Meeting 88-9 October 2003

Barrel SCT Mechanics - assembly at RAL -delays!

B3 cooling assembly at RAL

Thermal enclosure a major problem

Sils ATLAS Meeting 98-9 October 2003

SCT Mechanics - integration of barrels at CERN

A possible assembly sequence developed by the group for the 4 equipped barrels.

Sils ATLAS Meeting 108-9 October 2003

Barrel SCT Mechanics - preparing SR1 reception

Temporary enclosure

DAQ system & readout

DCS & power supplies

Facility control & monitor (CIC)

Cooling system

Environmental Control & Interlock

Detector services

Environmental Gas

From H. Pernegger