1. 24 September 2012 Immanuel Gfall (HEPHY Vienna) Annekathrin Frankenberger (HEPHY Vienna) SVD Status of Mechanics PXD-SVD Meeting Göttingen

2. SVD Status of Mechanics and Cooling Frozen Layout Layout requires fewer ladders which leads to a significant cost reduction Interference free layers 4,5,6 Acceptance is completely covered Ladder assembly and electrical wiring is compatible with this design Immanuel Gfall (HEPHY Vienna)24 September 2012 LayerRadius [mm]Ladder #Windmill °Overlap % 613516715.2 51051267.2 48010621.6 3387612.2 2

3. SVD Status of Mechanics and Cooling Layer 3 Design History Layer 3 had severe interference issues with layer 4 Even worse interferences with the support cones No space for connectors in layer 3 Solution required a new layer 3 approach Removal of support cones from layer 3 volume Cables can be soldered directly onto the hybrid boards This opens up the possibility to design a feasible layer 3 Immanuel Gfall (HEPHY Vienna)24 September 20123

4. SVD Status of Mechanics and Cooling Immanuel Gfall (HEPHY Vienna)24 September 2012 Layer 3 Design Idea The space for the layer 3 is defined by a tight envelope Layer 3 cables do not have to be routed inside of the SVD volume Support cones can become shorter to widen the space for PXD/SVD services Most feasible solution: Bridges Those bridges serve as a mechanical support and will need to provide sufficient thermal conductivity to cool the APV chips that are thermally coupled to the bridge Challenge: fit a fairly large object into a rather small volume 4

5. SVD Status of Mechanics and Cooling Layer 3 Immanuel Gfall (HEPHY Vienna)24 September 2012 Position pin Screw Rib contact surface 5 Layer 3 end ring is directly attached to the layer 4 ring

6. SVD Status of Mechanics and Cooling Ladder 3 Immanuel Gfall (HEPHY Vienna)24 September 2012 Backward bridge: longer than the forward bridge, has a fixed position and heat pipes Forward bridge: Trimmed to fit into the envelope, CTE compensation implemented with slots CFRP Ribs with Airex core 6 Cables are glued and soldered directly onto the hybrid boards

7. SVD Status of Mechanics and Cooling Bridges Immanuel Gfall (HEPHY Vienna)24 September 2012 Hybrid board connection points Precision hole Screw bore Precision slot Rib slots Cooling contact surface 7 Heat Pipe

8. SVD Status of Mechanics and Cooling Thermal Simulations Longest bridge: very bad heat conductivity Cooling is applied at the end ring -> heat transfer? Heat pipes are a possible answer Boundary Conditions: –Cold side: -20°C –Heat load: 4.8 W Simulation shows the blocks performance without improvements 8Immanuel Gfall (HEPHY Vienna)24 September 2012 11.4 °C Al 6061

9. SVD Status of Mechanics and Cooling Thermal Simulations 2 Cu only Max. temp: 8.2 °C Thermal conductivity: 401 W/ms 9Immanuel Gfall (HEPHY Vienna)24 September 2012 Heat pipes x10 Max. temp: -1.5 °C Thermal conductivity assumed: 4010 W/ms Heat pipes x100 Max. temp: -6.8 °C Thermal conductivity assumed: 40100 W/ms

10. SVD Status of Mechanics and Cooling Optimizations Design/ selection of a suitable heat pipe with 2 mm diameter Cooling surface and block should be milled from one piece Heat pipes should be in direct contact with the cooling surface All the above will be implemented in the FWD cooling block as well 10Immanuel Gfall (HEPHY Vienna)24 September 2012

11. SVD Status of Mechanics and Cooling Layer 3 Ribs Sensors are small and light enough to be self supporting A necessary glue bond between the sensors is not welcome Therefore self support is not reasonable Light support structure needed Low mass/small material budget is required Creep of Airex is not well known, thus the rib will be sandwiched with CFRP similar to the other SVD ribs Immanuel Gfall (HEPHY Vienna)24 September 2012 Airex rib sandwiched with CFRP Cut outs for the bond wire area 11

12. SVD Status of Mechanics and Cooling Layer 3 Endring Endring is directly attached to the layer 4 endring Connection screw holes need to be arranged asymmetric Support faces contain holes for precision pins and screw holes Cut outs in the inner radius of the ring provide larger service space Endring is designed so the base features can be machined in one step Holes need to be drilled after machining the base features Immanuel Gfall (HEPHY Vienna)24 September 201212

13. SVD Status of Mechanics and Cooling Improved Size Geometry of inner radius has been improved to increase service space 13Immanuel Gfall (HEPHY Vienna)24 September 2012

14. SVD Status of Mechanics and Cooling Interference check Immanuel Gfall (HEPHY Vienna)24 September 201214 Layer 4 mount structure Layer 3 mount structure

15. SVD Status of Mechanics and Cooling Layer 3 interference free with layer 4 Immanuel Gfall (HEPHY Vienna)24 September 2012 Outline free of interferences 15

16. SVD Status of Mechanics and Cooling Conclusion Layer 3 New layout includes Layer 3 Layer 3 fits all constraints Final touches on Layer 3 are a manageable task Immanuel Gfall (HEPHY Vienna)24 September 201216

17. SVD Status of Mechanics and Cooling Ladder Mount: SLM Updates SLM1 is a “Key-Lock” system Poor manufacturing makes this mechanism impractical SLM replacement was designed Immanuel Gfall (HEPHY Vienna)24 September 2012 SLM 17

18. SVD Status of Mechanics and Cooling SLM2 + 3 Backward mount of SVD needs to be locked and define the Ladders position Due to the Origami stack in this region limits the options for fastener positions to the front face of the endring Operation principle is shown in the drawings below Immanuel Gfall (HEPHY Vienna)24 September 201218 Locking screw Position Pin Tapered locking pins Position pin with fastening slot Tapered set screw

19. SVD Status of Mechanics and Cooling Most Likely Part A variation of SLM3 Single positioning pin with a conical locking bore 19Immanuel Gfall (HEPHY Vienna)24 September 2012 Position pin with positioning hole Precision hole Setscrew hole Cooling channel

20. SVD Status of Mechanics and Cooling SLM FWD Ladder Option Base on a suggestion from KEK Needs to be investigated if the mechanism is compatible with the Origami Scheme in Layer 6 20Immanuel Gfall (HEPHY Vienna)24 September 2012

21. SVD Status of Mechanics and Cooling Immediate Outlook Finalizing layer 3 + end ring End ring positioning elements will be added End ring locking mechanism will be included New design study of a hybrid support cone Prototype production of SLM studies Glue radiation hardness test run Assembly of Krakow mockup Finalizing end flange requirement document 21Immanuel Gfall (HEPHY Vienna)24 September 2012

22. SVD Status of Mechanics and Cooling 22Immanuel Gfall (HEPHY Vienna)24 September 2012 COOLING

23. SVD Status of Mechanics and Cooling 23namedate Tube diameter 1.6mm Hex head wrench size 5mm solder joint 18mm 31mm Miniature tube fitting Stainless steel Consisting of 3 parts Without seal Brazed at tube Screw together without twisting the tube Much smaller than conventional fittings

24. SVD Status of Mechanics and Cooling 24namedate Pressure Test Successfully pressure tests up to 200 bar –Miniature fitting –Cooling tube with 50µm wall thickness (1.6mm outer diameter)  No expansion in diameter  Small bending of tube visible (compensated by small tube holder clamps) Evaporator Coil Miniature Fitting

25. SVD Status of Mechanics and Cooling 25namedate Pressure test Tube diameter measurement Pressure [bar] D1 [mm] D2 [mm] D3 [mm] D4 [mm] D5 [mm] 11,591,581,561,611,58 1501,611,58 1,611,60 2001,59 1,571,601,59 D1 D2 D3 D4 D5