ATLAS Project Document No:
ATL-IS-CS-0018
Institute Document No. Created: 04/09/03
Modified: 16/04/20
Page:
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Abstract
This specification details the technical requirements relating to the manufacture and supply of the Thermal Enclosure for the ATLAS SCT Barrel Detector.
Prepared by:
Anthony Jones (Tony)
Peter Ford
Stephen Haywood
Checked by:
Andy Nichols
Lindsay Glover
Distribution List
The above, plus Steve McMahon
Approved by:
Richard Nickerson
Eric Perrin

1
2
3
3.1
3.2
3.3
3.4
4.0
Rev. No. Date
19/9/03
8/10/03
10/10/03
14/10/03
17/10/03
20/10/03
22/10/03
23/10/03
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Pages
Description of changes
Technical details supplied by Tony Jones.
Creation of separate Tender Form by Stephen Haywood.
After discussion with Andy Nichols.
After discussion with Petula Carter.
After discussion with Tony Jones.
Mods by Tony Jones.
Comments from Lindsay Glover.
Comments from Eric Perrin.

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1 OVERVIEW ............................................................................................................................................................................................... 5
1.1
The ATLAS Experiment ...................................................................................................................................................................... 5
1.2
The ATLAS Semiconductor Tracker ................................................................................................................................................... 5
1.3
The ATLAS SCT Barrel Thermal Enclosure ....................................................................................................................................... 5
1.4
RAL and CCLRC................................................................................................................................................................................. 5
2 DESCRIPTION OF THE THERMAL ENCLOSURE ........................................................................................................................... 6
2.1
Half Cylinders ...................................................................................................................................................................................... 6
2.2
Flat Side Panels .................................................................................................................................................................................... 6
2.3
Annular End Panels ............................................................................................................................................................................. 6
2.4
Inner Thermal Enclosure Cylinder ....................................................................................................................................................... 6
2.5
Bulkheads ............................................................................................................................................................................................ 7
2.6
Additions to Complete the Thermal Enclosure .................................................................................................................................... 7
2.7
Thermal Enclosure Test Sector Unit .................................................................................................................................................... 7
2.8
Operational Environment and Requirements ....................................................................................................................................... 7
2.8.1
Environment ................................................................................................................................................................................. 7
2.8.2
Requirements ............................................................................................................................................................................... 7
3 DRAWINGS ............................................................................................................................................................................................... 8
3.1
Drawing List ........................................................................................................................................................................................ 8
3.2
Modifications ....................................................................................................................................................................................... 8
3.3
Versions ............................................................................................................................................................................................... 8
3.4
Surface Quality, Finish and Cleanliness of the Components ............................................................................................................... 8
3.5
3D Models ........................................................................................................................................................................................... 8
4 MATERIALS AND COMPONENTS ...................................................................................................................................................... 8
4.1
Suggested Sources of Materials ........................................................................................................................................................... 9
4.1.1
CFRP Material ............................................................................................................................................................................ 9
4.1.2
Epoxy ........................................................................................................................................................................................... 9
4.2
Customer Supplied Components .......................................................................................................................................................... 9
4.3
Additional Requirements for Materials ................................................................................................................................................ 9
5 ALTERNATIVE BIDS .............................................................................................................................................................................. 9
6 TESTING AND METROLOGY .............................................................................................................................................................. 9
6.1
Verification of Materials ...................................................................................................................................................................... 9
6.2
Leak-testing for Panels ........................................................................................................................................................................ 9
6.3
Metrology .......................................................................................................................................................................................... 10
6.4
Fit-Check ........................................................................................................................................................................................... 10
6.5
Leak-testing for Assembled Thermal Enclosure ................................................................................................................................ 10
7 SCHEDULE ............................................................................................................................................................................................. 10
7.1
Programme Phases ............................................................................................................................................................................. 10
7.2
Delivery Dates ................................................................................................................................................................................... 11
8 PROGRAMME REQUIREMENTS ...................................................................................................................................................... 11
8.1
Pre-Contract Placement Review ........................................................................................................................................................ 11
8.2
Contract Execution ............................................................................................................................................................................ 11
8.3
Documentation ................................................................................................................................................................................... 12
8.3.1
Manufacturing Method and Sequence ........................................................................................................................................ 12
8.3.2
Product Assurance and Quality Assurance Plan ....................................................................................................................... 12
8.3.3
End-item Data Package ............................................................................................................................................................. 12
8.3.4
Progress Reports ........................................................................................................................................................................ 12
8.3.5
Deviations and Waivers ............................................................................................................................................................. 12
8.3.6
Emergency Reports .................................................................................................................................................................... 13
8.4
Reviews ............................................................................................................................................................................................. 13
8.4.1
Review of Manufacturing Work Instructions and End-item Test Plan ....................................................................................... 13
8.4.2
Review of TE design ................................................................................................................................................................... 13
8.4.3
Monthly Meetings....................................................................................................................................................................... 13
8.5
Notifiable Events ............................................................................................................................................................................... 13
9 PACKAGING AND DELIVERY OF HARDWARE ............................................................................................................................ 14
9.1
Packaging ........................................................................................................................................................................................... 14
9.2
Address .............................................................................................................................................................................................. 14

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10 TECHNICAL CONTACTS ................................................................................................................................................................ 15

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The ATLAS Experiment is a very large and extremely complex particle physics detector which is being constructed at CERN in Geneva and is scheduled to start data-taking in 2007. ATLAS is a large international project involving many collaborators from institutes from around the world. The experiment consists of a number of separate detectors, one surrounding another.
For a more details, refer to the ATLAS website at: http://atlas.web.cern.ch/ATLAS/Welcome.html
At the heart of ATLAS is a very delicate silicon tracking detector – the Semiconductor Track (SCT). This will track charged particles with precisions of 10  m. The SCT consists of a cylindrical Barrel section
(approximately 1.6 m long, with a radius of 0.55 m) and two End-caps.
The silicon of the SCT is required to run at a temperature of –7 o C in a dry N
2
environment. For the SCT
Barrel, this environment is maintained by the SCT Barrel Thermal Enclosure (TE). The SCT Barrel is surrounded by CO
2
, and the TE must ensure that there is no exchange of the two environmental gases.
The TE consists of he following subassemblies:
 Two identical half cylinders,
 Two identical flat side panels,
 Two identical annular end panels,
 One Inner Thermal Enclosure (ITE) cylinder.
The SCT Barrel TE is being designed and assembled at the Rutherford Appleton Laboratory (RAL), situated near Oxford, England. RAL is part of the Council of the Central Laboratory of the Research
Councils (CCLRC).

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This section provides a simplified description of the components of the TE. The complete description is
provided by the Drawings – see Section 3.
Upper half cylinder
Flat side panels (2 off)
Lower half cylinder
Dummy bulkheads
(2 off)
ITE cylinder
Annular end panels (2 off)
Each half cylinder is constructed from five cylindrical panel sub-assemblies bonded together. Each panel has inner and outer walls of carbon-fibre, separated by strips of Airex  foam or equivalent, and is filled with dry carbon dioxide gas to improve thermal insulation characteristics.
Each panel has inner and outer walls of carbon-fibre with hollow carbon-fibre inner-rail sections at the top and bottom edges and aluminium-alloy end-fixing brackets. The separation between the walls is filled with aerogel panels in evacuated plastic bags.
Each panel has inner and outer walls of carbon-fibre, separated by strips of Airex  foam or equivalent.
The separation between the walls is filled with aerogel panels in evacuated plastic bags. Each outer wall contains eight channels.
This is a carbon-fibre laminate cylinder, joined to the Annular End Panels by EPDM seals.

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The Outer TE cylinder will be connected to each Annular End Panel by a Bulkhead which will allow electrical, optical-fibre and cooling services to leave the silicon tracking detector through the TE. For the trial assembly of the TE, CCLRC will provide dummy bulkheads.
To give the TE its necessary functionality, it will have heater pads placed on the entire outer surface, and cooling circuits attached to the inner surface of the half cylinders. These will be attached to heatspreading foils which will act as a Faraday cage. The supply of these parts is not part of this tendering action. The heating/cooling power will be of the order of 300 W/m 2 , resulting in a total of 2600 W of heating over the whole of the TE’s outer surface.
As a first step to verify the design of the TE, a Test Sector Unit (TETSU) shall be manufactured. The
TETSU will consist of:
 A representation of the cylindrical part of the TE, comprising two cylindrical panels, identical to those in the final TE, albeit that one is slightly narrower.
 Two Flat Side Panels, identical to those in the final TE,
 Two end panels which will be of a simpler design than those in the final TE.
2.8.1
Environment
 Accessibility : once installed in the ATLAS Experiment, there will be very little chance for access, hence reliability is a key requirement.
 Radiation : materials are required to be radiation hard up to a fluence of 2  10 15 n/cm 2 (1MeV neutrons) or 3  10 7 Gray, representing 10 years of operational life inside ATLAS.
 Activation : materials should not become significantly activated as a result of the irradiation.
 Magnetic field: the SCT will sit in a 2 T magnetic field, therefore magnetic materials should be avoided wherever possible.
2.8.2
Requirements
 Internal temperature :  7 o C.
 External temperature : +20 o C.
 Pressure : tolerate internal pressures up to 4 mbar above local atmospheric pressure.
 Leak rate : must be less than 6 l/mbar/hour.
 Mass : should have a minimal mass (actually what is desired is a minimum number of radiation lengths).
 Envelope : the space between the silicon tracking detector and the inside of the TE, and surrounding detectors and the outside of the TE is critical. Therefore it is essential that the tolerances specified on drawing are achieved.
 CTE: must be  5  10  6 K  1 to ensure the TE remains within envelopes and avoids stresses.

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The design of the ATLAS SCT Barrel TE is contained in the following top-level assembly drawings (and the drawings to which they point):
TD-1020-164 General Assembly
TD-1020-120 Half Cylinders
TD-1020-400 Flat Side Panels
TD-1020-267 Annular End Panels
TD-1020-270 ITE Cylinder
TD-1034-170 Assembly of Test Sector Unit
TD-1034-240 Test Sector Unit End Panels
For the general tolerances listed in these drawings, ISO 2768 and ISO 8015 are applicable unless otherwise stated.
At the time of the Contract Placement, a complete set of approved drawings will be issued.
CCLRC reserves the right to make minor changes to the above mentioned drawings before manufacturing begins – “ TBC” appears adjacent to those dimensions which need To Be Confirmed.
CCLRC will consider any small modifications proposed by the Bidder for production reasons, provided they do not affect the general performance requirements. All “TBC”s and modifications shall be clarified by formal modifications notices. If there is any uncertainty, the Contractor must not go ahead and shall contact CCLRC immediately to obtain clarification.
For production , the final drawings shall be approved in writing by CCLRC. They will be denoted by
“ REL ” in the status box.
The face-sheets of the panels will be equipped by CCLRC or its collaborators with various fixtures. The surface finish and roughness for the composite parts are described in the drawings. Deviations from these specifications may be accepted by CCLRC after submission of a written request and inspection by
CCLRC. The written approval of CCLRC must be obtained before any work is undertaken by the
Contractor to rectify surface faults.
As bonding to the components will take place after Provisional Acceptance, any cleaning procedure shall be declared to CCLRC in writing for approval.
The 2D Drawings have been obtained from 3D Models created using Pro/ENGINEER software. The 2D drawings with their respective issue letters form the definitive drawings for this Contract. On request,
CCLRC may provide the 3D Models as IGES or STEP files; however, in this case, responsibility for the use of these files lies entirely with the Contractor. The Contractor shall be responsible for notifying
CCLRC immediately of any discrepancies he finds between the 2D Drawings and the 3D Models.
The Contractor shall be responsible for the design and manufacture of all tooling required for the programme. The Contractor shall procure sufficient of all the required materials. The Contractor shall procure materials to established materials specifications that have been reviewed by CCLRC.

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4.1.1
CFRP Material
The CFRP material specified on the drawings type T300/CX-920-820-47.5%. It has been chosen because of its:
 Stiffness: 105 GPa perpendicular to weave direction,
 Radiation resistance: <5% reduction in strength after 2  10 5 Gy,
 Low CTE: 5  10  6 K  1 .
For further information on this material and the processing procedures etc., contact the suppliers.
If requested, CCLRC can suggest possible suppliers of this material.
4.1.2
Epoxy
The epoxy adhesive specified on the drawings type Araldite 2011 (AW106/HV953U), 100/80 pbw.
Alternatively Araldite 138 or Hysol EA9396 may be used, in which case written agreement must be obtained from CCLRC for either of these epoxies.
For further information on this material and the processing procedures etc., contact the suppliers.
If requested, CCLRC can suggest possible suppliers of this material.
 Dummy bulkheads.
The materials proposed by CCLRC satisfy the CERN fire safety regulations and do not emit substances
(e.g. acetic acid) before or after irradiation which might damage the silicon detectors.
Should a Bidder wish to propose alternative materials, he must provide evidence that these materials satisfy the above requirements. Further details pertaining to these requirements may be obtained from the
CCLRC Contacts listed in Section 10.
If a Bidder proposes to use any materials, in particular metals, which are not specified on the supplied drawings, he must declare it in writing to CCLRC and must not use these materials until authorised by
CCLRC.
In addition to Conforming Bids, CCLRC welcomes Alternative Bids which provide improvements with respect to cost, production schedule, manufacturing processes or performance.
It is necessary that any alternative designs should satisfy the requirements set out in Section 2.8. Any
proposal for the use of alternative materials must provide evidence that they are of at least equivalent standard as those proposed by CCLRC.
For all tests identified in this section, the Contractor shall invite CCLRC representatives to attend, giving at least one week’s notice.
The Contractor shall ensure that material is procured to defined specifications, with appropriate material certification. The Contractor is responsible for validating the quality and performance of the material received and used at all times. No material shall be used after its specified shelf-life without written agreement from CCLRC.
The Contractor is responsible for leak-testing each cylindrical panel (including those in the TETSU). This test shall be performed at a pressure of 10 mbar above atmospheric pressure using dry nitrogen gas. The

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existence of leaks may be located using Rocol  Leak Detector Spray or similar, but only with prior permission from CCLRC in writing.
The requirement is that there should be no leaks in the panels. If leaks are found, then possible solutions for fixing the leaks shall be discussed with CCLRC before any action is taken.
The requirements are set out in Metrology of the ATLAS SCT Barrel Thermal Enclosure (ATL-IS-ER-
0050).
CCLRC will be responsible for the Metrology which will take place at the Contractor’s premises.
The Contractor will be responsible for performing a Fit-Check of all components of the TETSU and TE, including the dummy bulkheads for the TE.
The requirements are set out in Metrology of the ATLAS SCT Barrel Thermal Enclosure (ATL-IS-ER-
0050).
CCLRC will be responsible for leak-testing the complete carbon-fibre TE, with the inclusion of the
dummy bulkheads. This test will take place at the delivery destination indicated in Section 9.2. Contractor
representatives may attend these tests.
The requirements for the total leak rate are set out in Section 2.8.
The Programme shall be executed in five phases. These phases shall include but not be limited to:
Phase 0 – Tendering and Contract Placement
Invitation to Tender
Contractor Selection
Finalisation of Contract
Finalisation of Drawing List
Pre-Placement Contract Review
Award of Contract
Phase 1 – Preparation
Delivery of materials and components to Contractor
Fabrication of Tooling
Review of Manufacturing Work Instructions and Test Plan
Phase 2 – Construction of the TETSU
Manufacture of components of the TETSU
Testing of components of the TETSU
Assembly of the TETSU
Delivery of the TETSU
Provisional Acceptance of the TETSU by CCLRC
Review of the TE design

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Phase 3 – Construction of TE
Manufacture of components of the TE
Testing of components of the TE
Assembly of the TE subassemblies
Delivery of the TE subassemblies
Testing of the complete assembly by CCLRC
Provisional Acceptance of the TE by CCLRC
Phase 4 – Completion
Delivery of tooling and remaining materials to CCLRC
The schedule for the delivery of the hardware to the address given in Section 9 are as follows:
 TE Test Sector Unit
 Barrel TE
11 weeks
28 weeks
after the signing of the Contract.
after the signing of the Contract.
The schedule for the delivery of the Barrel TE includes the time taken for the Provisional Acceptance of the TETSU.
Delivery of the hardware must be preceded by successful verification of the metrology of the hardware and successful leak-tests of the cylindrical panels.
The selected Bidder shall work concurrently with CCLRC before Contract placement to finalise the design details to ensure that the manufactured product meets the performance requirements.
CCLRC reserves the right to hold a Pre-Contract Placement Review as a final check of Contract details.
This review will take place at the Contractor’s premises and include representatives of the Contractor and
CCLRC. During this review the following subjects will be discussed and reviewed:
 Any outstanding issues on heritage, experience, facilities, equipment and capability,
 Any alternative design proposals,
 Programme planning and programme team,
 Detailed Production Assurance and Quality Assurance (PA&QA) plan.
The Contractor shall appoint a Programme Manager , to be responsible for the Contract and its followup including all contacts with CCLRC throughout the duration of the Contract. The Programme Manager shall manage his resources to assure timely completion of the work specified herein. The Programme
Manager shall maintain close technical and managerial liaison with CCLRC.
CCLRC reserves the right to place a resident at the Contractor’s facility during the programme period.
CCLRC reserves the right to have free access during normal working hours to the manufacturing or assembly sites, including any subcontractor’s premises, during the Contract period.
The Contractor shall inform CCLRC immediately in writing of any changes with respect to the Contract incurred during production. CCLRC will then give its approval or refusal also in writing.
The language of all correspondence shall be English.

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The documentation to be delivered by the Contractor to CCLRC shall include but not be limited to:
Phase 0
The documentation listed in the Invitation to Tender
Phase 1
Master Schedule
Manufacturing, Inspection and End-item Test Plan
Final PA&QA Plan
Test Procedures
Phases 2-3
Deviations and Waivers – as necessary
Emergency Reports – as necessary
End-item Data Package
Phases 1-3
Regular Progress Reports
8.3.1
Manufacturing Method and Sequence
This (required in Phase 0) should include a complete description of the manufacturing method and sequence, including possible post-fabrication treatments.
8.3.2
Product Assurance and Quality Assurance Plan
This plan should be compliant with ISO9001 or an equivalent standard.
8.3.3
End-item Data Package
Each delivered piece of hardware (the subassemblies of the TETSU and the TE) shall have its own Enditem Data Package which shall include but not be limited to:
 Copies of all Certificates of Conformance of the procured materials,
 A list of all material and component batch numbers,
 Results of incoming receiving inspection and testing for materials used,
 Results of inspections and tests performed on the hardware supplied, as set out in the End-item
Test Plan ,
 Copies of all non-conformances, deviations, discrepancy reports, waivers including their approvals from CCLRC for the hardware supplied,
 Certificate of Conformance for the hardware supplied,
 Declared Materials and Processes list.
8.3.4
Progress Reports
A written progress report shall be sent by email to the CCLRC Technical Contact given in Section 10
every fortnight until completion of the Contract.
This progress report shall:
 Provide a description of accomplishments,
 Highlight issues requiring action and identify the required action,
 Show the current status vs. the Master Schedule,
 Show the status of long-lead items.
8.3.5
Deviations and Waivers
It is at the sole discretion of CCLRC to accept or reject hardware associated with a non-conformance unless an approved Deviation or Waiver has been received by the Contractor.

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8.3.6
Emergency Reports
The Contractor shall issue an Emergency Report in the event that any occurrence (including but not limited to mishaps, discrepancies, failures or other types of non-conformances occurring during manufacturing, testing or operations) which may delay or hinder the achievement of a key event. The
Contractor shall submit within 48 hours of the occurrence by fax or email a report which shall inform
CCLRC of the nature of the occurrence, possible impacts on the programme and suggested plan of action.
8.4.1
Review of Manufacturing Work Instructions and End-item Test Plan
Prior to giving go-ahead in writing for fabrication of the deliverable hardware, a Manufacturing Work
Instruction Review will be held at the Contractor facility. The purpose of the review is to demonstrate that all the requirements of this programme and technical specification can be met.
The review shall contain as a minimum all the detailed work instructions necessary for the fabrication and testing of the hardware. These instructions shall include but not be limited to:
 Detailed fabrication steps and reference to any established procedures or processes,
 Inspection steps, reference to inspection procedure, accept/reject criteria,
 Notifiable events,
 Tooling references and applicable drawings,
 Calibration control of all tooling,
 Product conditioning (as required).
In addition, the Contractor shall present the End-item Test Plan which he intends to follow. The End-item
Test Plan shall include:
 Tests to be performed on the deliverable hardware,
 Test procedure,
 Tooling and equipment description including their calibration control status,
 Accept and reject criteria.
8.4.2
Review of TE design
The purpose of the construction of the TETSU is to verify the design for the TE. CCLRC reserves the right to modify the design of the TE after the completion of the TETSU and before the construction of the
TE.
Following the manufacture and testing of the TETSU, a review will be held to consider possible modifications to the TE design.
The Contractor shall not start manufacture of the components of the TE until authorised in writing by
CCLRC. Any changes to the design requested by CCLRC will be subject to satisfactory contractual discussions between CCLRC and the Contractor.
8.4.3
Monthly Meetings
There will be monthly meetings between CCLRC and the Contractor to review the progress. The nature of these meetings will be determined by CCLRC and will either be by phone or at the Contractor’s premeses.
The Contractor shall notify CCLRC at least five working days in advance of the following events:
 Leak-testing of components of the TETSU or TE,
 Metrology of the TETSU or TE,
 Shipping of the TETSU or TE.

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The packaging and method of delivery shall be such that the physical integrity is maintained and not affected by the packaging and method of transport chosen. The packaging and method of transport shall prevent damage, theft and loss, contamination of any form, degradation, and exposure to any elements that may affect the performance of the hardware.
Each subassembly of the hardware (listed in Section 1.3) is to be packed separately in static-free plastic
bags. Each item inside its bag should be purged with dry nitrogen before the bag is sealed and a dry activated desiccant should be included in the bag. It is the responsibility of the Contractor to ensure that the hardware is protected during shipping and that the shipping container does not transfer loads, shock or other environments that may degrade the hardware.
The marking and labelling of the protective bag and shipping container shall include, but not be limited to, the following:

Shipping Address and Technical Contact (given in Section 9.2).
 Instruction to contact the Technical Contact at the point of delivery upon arrival.
 Contents description.
 Orientation for opening and storage “THIS SIDE UP”.
 Unpacking instructions (or their location).
 Location of travel documents.
 In addition the words “FRAGILE-HIGH-RELIABILITY COMPONENTS”.
The container should be supplied with equipment to record the temperature and humidity .
All deliverables shall be sent to
Mr. A. Jones
CCLRC
Rutherford Appleton Laboratory
Chilton
Didcot
OX11 0QX
United Kingdom

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Further information and clarification of the requirements in this document can be obtained from the RAL project team:
Primary Contact:
Mr. A. Jones
Tel. N o (44) 01235 446331
Fax. N o (44) 01235 446863
E-mail A.Jones@rl.ac.uk
Other Contacts:
Mr. A. Nichols
Tel. N o (44) 01235 445251
Fax. N o (44) 01235 446863
E-mail A.Nichols@rl.ac.uk
and
Mr. P. Ford
Tel. N o (44) 01235 445626
Fax. N o (44) 01235 446863
E-mail P.Ford@rl.ac.uk