Stave - Electrical Break

Richard FrenchThe University of Sheffield

Material from the ATLAS SCT/IBL/PIXEL community

ID gas barrier

Pixel detector EC SCT Barrel SCT

PP0

PPF1

PP1b

PP1a

PPB1

PPF0

PPB0

Distribution racks (PP3)

PP2b

PP2a at cryostat flange

Z = 0

Along Tile Calorimeter Barrel

Platform #7 or #1 level

R=1300 mm Z=3330 mm

R=2000 mm Z=3550 mm

R=2775 mm Z=3450 mm

R=4240 mm Z=2900 mm

Distance from PPF1 to PP2b – 220+700+100+775+550+1465=3810 mm=3.8 m

Heat exchanger

Heater

ID gas barrier

Pixel detector EC SCT Barrel SCT

PP0

PPF1

PP1b

PP1a

PPB1

PPF0

PPB0

Z = 0 Heat exchanger

Heater

Figure 1: Location of cooling components and external pipe destinations in ATLAS [Error! Bookmark not defined.,1]. [1] Pierre Bonneau, Technical Specification, Evaporative Cooling System for ATLAS Inner Detector

Silicon Trackers (Pixel and SCT): external part, WORK UNIT 1 . ATC-TL-EP-0001, EDMS N°391168

Location of cooling components and pipe destinations in ATLAS

Services routing of current ID from PP2

• How much of the wheel needs reinventing?

• Can we tweak an existing design?

• For reference – is the positional terminology the same?

Existing ATLAS layout and terminology to jog memory

• Electrical break on barrel was done with Beryllia. • Cooling pipe was copper-nickel.

• Upgrade uses Titanium as a baseline for Stave core.• CuNi was used for on detector pipework

• Do we have a baseline (CP2 Ti)?• Stainless steel (austenitic) was used for off detector

• What is our baseline? 316L?• C106 soft annealed copper was also used in small

amounts for manufacture of Heat Exchangers (HEX), S bends and other short lengths of tube both on and off detector• Not ideal.

• Unfilled PEEK tube (specially made 12mm ID 13mm OD) was used for gas ‘guidance’ of N2 dry gas around the detector.• Not thought about yet for N2 delivery.

Existing materials used in ATLAS SCT cooling system

Items to consider before addressing design of electrical break connectorGALVANIC STABILITY OF THE SYSTEM

ITE

Disc 1

Cu-Kapton (or Al-Kapton) Aluminsed Kapton Carbon fibre Foam Services Cu-Kapton (or Al-Kapton) tab or Litz wire

Disc 9

Module

Module

Shunt Shield

Shunt Shield

Thermal Pad

Support Pad

Wiggly Tape

PPF0/e

Support Cylinder

OTE

Front Support

Rear Membrane

Front Membrane

Cooling Pipe

LMT Insulating Break Ground

Sheet

STFT

PPF0/c

Grounding Foil

Cooling Interconnect

Rear Support

physical contact

connect to RCT

End-cap G&S Version 1.6 5/9/06

Rail

Disc Fixation

EC-A See Note Error! Reference source not found.

EC-C See Note Error! Reference source not found.

Endcap disks have ground referencing tapes that bond together the complex cooling tube paths.

SCT Endcap Grounding and Shielding Scheme

https://indico.cern.ch/getFile.py/access?contribId=5&resId=0&materialId=slides&confId=206624

Life gets much simpler with the current proposal from Ned.

• Location of electrical break does not matter so either at • PPB0

Or• PPB???? 1ish.

• Decided at RAL meeting to concentrate at end of Stave option.• Mass implication?• Materials choice• CRITICAL JOINT• Encapsulate connector

at end of Stave• OD???• Diameter

transition

Quick peek at IBL progress

• 3 connector types• Brazed union• De-mountable connector with swaged tube• Electrical break (brazed ceramic)• OD crucial to encapsulation in Stave.• Conductivity with carbon fibre skins

IBL Electrical Break and Connectors

2.5 to 1.7 OD 1.7 to 2.2 OD1.7 and 2.2 OD

• 316L tube – ceramic – titanium tube isolator

• Diameter transition of tube• OD can be reduced• Length ok• Can be encapsulated• Need to better understand

purpose of covers.

• Attempt to make simplified, similar item using brazed ceramic • Material type?• Reduce size

• Ti to Ti joining preferred as simpler

• OD/ID v working pressure• Volume / Quantity required to

fit with new programme?• Services mock up?• Introduce to prototype

staves.

2.5 1.7