1. 1ESAComp Users’ Meeting 2006 University of Applied Sciences of Northwestern Switzerland March 2–3, 2006 High-Precision Composite Support Structures for CERN Tracking Detectors Harri Katajisto Componeering Inc. / Helsinki Institute of Physics ESAComp Users’ Meeting 2006 University of Applied Sciences of Northwestern Switzerland March 2–3, 2006

2. 2 CERN OUTLINE LHC CMS TOB

3. 3ESAComp Users’ Meeting 2006 University of Applied Sciences of Northwestern Switzerland March 2–3, 2006 CERN = European Organization for Nuclear Research Founded in 1954, today 20 member states CERN The world’s largest particle physics centre with scientists from 500 universities and 80 countries

4. 4ESAComp Users’ Meeting 2006 University of Applied Sciences of Northwestern Switzerland March 2–3, 2006 Goal: Study what matter is made of and what forces hold it together CERN

5. 5ESAComp Users’ Meeting 2006 University of Applied Sciences of Northwestern Switzerland March 2–3, 2006 CERN provides tools for the scientists: Accelerators and Colliders that accelerate particles to almost the speed of light and make them collide and Detectors to make the particles visible CERN

6. 6ESAComp Users’ Meeting 2006 University of Applied Sciences of Northwestern Switzerland March 2–3, 2006 Large Hadron Collider, LHC, CERN’s present main project, due to start in year 2007 Will collide beams of protons at an energy of 14 TeV 1 TeV is about the energy of motion of a flying mosquito. LHC squeezes that energy into a space about a million million times smaller than a mosquito. LHC

7. 7ESAComp Users’ Meeting 2006 University of Applied Sciences of Northwestern Switzerland March 2–3, 2006 LHC

8. 8ESAComp Users’ Meeting 2006 University of Applied Sciences of Northwestern Switzerland March 2–3, 2006 CMS Experiment Diameter 15 m Length 21.5 m Mass 12500 tons

9. 9ESAComp Users’ Meeting 2006 University of Applied Sciences of Northwestern Switzerland March 2–3, 2006 CMS Experiment

10. 10ESAComp Users’ Meeting 2006 University of Applied Sciences of Northwestern Switzerland March 2–3, 2006 768 narrow strips side by side on the silicon substrate work as the tracker’s eyes High conductivity CFRP support frame (240 mm x 130 mm) Read-out electronics and cabling CMS Tracker

11. 11ESAComp Users’ Meeting 2006 University of Applied Sciences of Northwestern Switzerland March 2–3, 2006 This simple layout means: CMS Tracker Layout 15000 x + control electronics + optical links + cables = 50 kW, 25 kA, 1500 kg

12. 12ESAComp Users’ Meeting 2006 University of Applied Sciences of Northwestern Switzerland March 2–3, 2006 CMS Tracker Layout 2.4 m 5.4 m Tracker Outer Barrel, TOB Inner Barrel Inner Disks End Caps Pixel detector Beam pipe

13. 13ESAComp Users’ Meeting 2006 University of Applied Sciences of Northwestern Switzerland March 2–3, 2006 Measurement of particle tracks with 50  m precision in a volume of 5.4 m in length and 2.4 m in diameter High initial precision (strip positions known to ~ 0.3 mm) Large, dimensionally very stable structures (0.000050 m vs. 5.4 m !) Transparency to particles Minimize material Use transparent materials (low Z) High magnetic field (4 Tesla) Non-magnetic materials Tracker Requirements

14. 14ESAComp Users’ Meeting 2006 University of Applied Sciences of Northwestern Switzerland March 2–3, 2006 Favored materials CFRP Plastics Light metals Tracker Requirements

15. 15ESAComp Users’ Meeting 2006 University of Applied Sciences of Northwestern Switzerland March 2–3, 2006 Remove heat load, keep silicon at -10 °C High-performance cooling system Reach all heat sources, protect silicon from local hot spots Dimensional stability under changing temperature (+20 °C - -20°C) and change of humidity (normal room conditions to very dry) 10+ years of operation, but very little possibilities for maintenance and repair (almost impossible to access; radio activation) Satellite-level of reliability and high quality are a must Tracker Requirements

16. 16ESAComp Users’ Meeting 2006 University of Applied Sciences of Northwestern Switzerland March 2–3, 2006 Main responsible parties of the TOB construction: CERN Fermi National Accelerator Laboratory (USA) Helsinki Institute of Physics (FIN) University of California, Santa Barbara (USA) TOB Parties

17. 17ESAComp Users’ Meeting 2006 University of Applied Sciences of Northwestern Switzerland March 2–3, 2006 Wheel Barrel-like structure that supports 688 rods Rod Modular support structure that contains the detectors and services TOB Components

18. 18ESAComp Users’ Meeting 2006 University of Applied Sciences of Northwestern Switzerland March 2–3, 2006 CFRP profiles Rod support Al-inserts TOB Rod Detector support Al- inserts CuNi cooling pipes

19. 19ESAComp Users’ Meeting 2006 University of Applied Sciences of Northwestern Switzerland March 2–3, 2006 Pultrusion + 2000 m Wall thickness 0.9 mm Rod CFRP Profiles

20. 20ESAComp Users’ Meeting 2006 University of Applied Sciences of Northwestern Switzerland March 2–3, 2006 Water-jet cutting Economical Accurate Ready-to-use Rod CFRP Profiles

21. 21ESAComp Users’ Meeting 2006 University of Applied Sciences of Northwestern Switzerland March 2–3, 2006 Massive Al assembly jigs with machined contact surfaces and locator holes Rotator benches 2 technicians Rod Frame Assembly

22. 22ESAComp Users’ Meeting 2006 University of Applied Sciences of Northwestern Switzerland March 2–3, 2006 Al-inserts give the accuracy CFRP pieces work only as a skeleton Supported “freely” Clearances between Al-inserts and CFRP pieces were filled with low viscosity epoxy Low shrinkage, 20h curing at RT Assembly procedure fast Magnet counter parts on jigs and clamping units Rod Frame Assembly

23. 23ESAComp Users’ Meeting 2006 University of Applied Sciences of Northwestern Switzerland March 2–3, 2006 753 rod frames 688 + 65 spares 113 pieces / rod frame 85000 pieces in total ! Yield rate over 99% Rod Frame Assembly

24. 24ESAComp Users’ Meeting 2006 University of Applied Sciences of Northwestern Switzerland March 2–3, 2006 3D coordinate measurement In collaboration with Laboratory of Machine Design, Helsinki University of Technology Planning Tooling Measurement Data processing Qualifying Rod Frame Measurement

25. 25ESAComp Users’ Meeting 2006 University of Applied Sciences of Northwestern Switzerland March 2–3, 2006 3D coordinate measurement 168 measurement point / frame 126500 measurement points in total 10 minutes / frame Rod Frame Measurement

26. 26ESAComp Users’ Meeting 2006 University of Applied Sciences of Northwestern Switzerland March 2–3, 2006 Rod Frame Measurement

27. 27ESAComp Users’ Meeting 2006 University of Applied Sciences of Northwestern Switzerland March 2–3, 2006 Sandwich outer and inner cylinders 4 disks made of CFRP solid laminates CFRP support rails at the inner cylinder Support elements at the outer cylinder Al-inserts and attachment elements TOB Wheel

28. 28ESAComp Users’ Meeting 2006 University of Applied Sciences of Northwestern Switzerland March 2–3, 2006 T300 prepreg 2 mm thick quasi- isotropic skin laminates, qty 8 Level mould Autoclave curing Water-jet cutting TOB Skins

29. 29ESAComp Users’ Meeting 2006 University of Applied Sciences of Northwestern Switzerland March 2–3, 2006 Cast Al blank Machining allowances Planarity by lathe machining Locator hole drilling TOB Assembly Table

30. 30ESAComp Users’ Meeting 2006 University of Applied Sciences of Northwestern Switzerland March 2–3, 2006 A disk consists of 2 skins and vertical webs PEI inserts for holding rods Epoxy TOB Disk Assembly

31. 31ESAComp Users’ Meeting 2006 University of Applied Sciences of Northwestern Switzerland March 2–3, 2006 CFRP-Nomex sandwich 0.5 mm face sheets, quasi-isotropic lay-up Face sheets and core Post-bonded in autoclave TOB Cylinders

32. 32ESAComp Users’ Meeting 2006 University of Applied Sciences of Northwestern Switzerland March 2–3, 2006 Measurement with Theodolites Photogrammetry Slide calipers Rulers Correct shape Better than 0.2 mm TOB Wheel

33. 33ESAComp Users’ Meeting 2006 University of Applied Sciences of Northwestern Switzerland March 2–3, 2006 Geometry unchanged within 0.15 mm after rotation from the vertical to horizontal position and on the final supports TOB Wheel

34. 34ESAComp Users’ Meeting 2006 University of Applied Sciences of Northwestern Switzerland March 2–3, 2006 ESAComp ANSYS Analytical solutions ESA Insert Design Handbook TOB Analyses

35. 35ESAComp Users’ Meeting 2006 University of Applied Sciences of Northwestern Switzerland March 2–3, 2006 ESAComp 1.5 … Data Bank Laminate analysis FE export Bonded joints Mechanical joints TOB Analyses

36. 36ESAComp Users’ Meeting 2006 University of Applied Sciences of Northwestern Switzerland March 2–3, 2006 Special thanks are due to Mr. Antti Onnela from CERN Acknowledgements