1. ILC Main Linac Superconducting Quadrupole V. Kashikhin for Superconducting Magnet Team

2. TILC09, Tsukuba April 16-21, 2009 2 Outline Split quadrupole issues Quadrupole concept Conductive cooling Magnetic design Installation and disassembly Summary

3. TILC09, Tsukuba April 16-21, 2009 3 Split Quadrupole Concept Design Team Miao Yu- Cooling down analysis Mauricio Lopes- Magnetic center shift Yuri Orlov- 3D design and integration Vladimir Kashikhin- Magnet concept The Quadrupole concept was designed in short period of time by:

4. TILC09, Tsukuba April 16-21, 2009 4 Splittable Quadrupole Issues Task from ILC Project Management: Look at the Split Quadrupole conceptual design to provide the quadrupole package installation and replacement outside of a very clean room. Main issues: Stable magnetic and mechanical design; Effective conductive cooling; Easy installation and disassembly; Quadrupole+BPM rigid connection; Magnetic axis stability; Quench protection.

5. TILC09, Tsukuba April 16-21, 2009 5 ILC Quadrupole Specification

6. TILC09, Tsukuba April 16-21, 2009 6 Quadrupole Mechanical Concept It was chosen the quadrupole design with racetrack coils which easy to split in vertical or horizontal direction.

7. TILC09, Tsukuba April 16-21, 2009 7 Quadrupole Fabrication Qudrupole laminated yoke consists of two halfes; Laminations stamped with accuracy 20 microns; Long calibrated rods connect two thick side plates and laminations in the solid unit; Two coils mounted in each half core. There is an easy assess to provide accurate coil mounting relatively pole and provide the coil frame prestress; The half units identical and exchangable; All current leads should be heavily stabilized with extra copper material. Split plane Built and Tested Quadrupole Model 1

8. TILC09, Tsukuba April 16-21, 2009 8 Quadrupole Wiring Scheme Quadrupole consists of 4 coils. Each coil has 3 sections of NbTi superconductor: one is for quadrupole and two for vertical and horizontal dipoles. There is also heaters in each coil wound from a stainless steel wire. Quadrupole and dipole sections connected in quadrupole and dipole configuration as shown in figure. The connections easy to rearrange for split configuration Split line

9. TILC09, Tsukuba April 16-21, 2009 9 Quadrupole Cooling-Down The quadrupole will be cooled using conductive cooling; Five heat transfer leads will thermally connect quadrupole core and LHe supply line; The cross-section of leads 50 mm x 10 mm; Cooling down time for the cryomodule is 30 hours; During cooling initially the cold He gas goes through supply line and temperature changes from 300 K to 2 K. In such regime the enthalpy of the cold gas between 4.2 K and 300 K is utilized as well; To cool down 1 kg steel from 300 K to 2 K is needed to evaporate 0.8 liters of LHe; The quadrupole mass is ~ 280 kg.

10. TILC09, Tsukuba April 16-21, 2009 10 Conductive Cooling Animation Quadrupole cooled down from 300K to 3.5K in 38 hours.

11. TILC09, Tsukuba April 16-21, 2009 11 Magnet Assembly Tolerances Case #Description 0Standard ML quadrupole. Gradient 54 T/m. No correction coils. 1Right half of the magnet displaced 40 microns up. 21st Quadrant displaced 40 microns up. 31st Quadrant displaced 40 microns right and 40 microns up. 4Coil displaced 100 microns up. 5Coil displaced 100 microns up and 100 microns right. N1 40um up N2 40um up N3 57um up N4 100um up N5 140um 1 unit = 1 Gauss= 1um Magnetic center shift in microns

12. TILC09, Tsukuba April 16-21, 2009 12 Quadrupole Blocks Half QuadrupoleQuadrupole AssemblyQuadrupole with Cooling Leads

13. TILC09, Tsukuba April 16-21, 2009 13 Half Quadrupole with Beam Pipe View Half Quadrupole Yoke Beam Pipe Quadrupole-BPM Connection Flange Quadrupole Supports

14. TILC09, Tsukuba April 16-21, 2009 14 Quadrupole with Beam Pipe View

15. TILC09, Tsukuba April 16-21, 2009 15 Quadrupole with BPM

16. TILC09, Tsukuba April 16-21, 2009 16 Cryomodule Cross-Section Quadrupole Package 2 Phase He Supply Pipe

17. TILC09, Tsukuba April 16-21, 2009 17 Quadrupole with BPM Cross-Section QuadrupoleBPM

18. TILC09, Tsukuba April 16-21, 2009 18 Cryomodule Cross-Section

19. TILC09, Tsukuba April 16-21, 2009 19 Quadrupole Side View

20. TILC09, Tsukuba April 16-21, 2009 20 Cryomodule Cross-Section

21. TILC09, Tsukuba April 16-21, 2009 21 Cryomodule Cross-Section 3D View (1)

22. TILC09, Tsukuba April 16-21, 2009 22 Cryomodule Cross-Section 3D View(2)

23. TILC09, Tsukuba April 16-21, 2009 23 Quadrupole Final Assembly View QuadrupoleCooling LeadsBPMCurrent Leads

24. TILC09, Tsukuba April 16-21, 2009 24 Summary The first look at the splittable quadrupole showed this approach visibility; Proposed the quadrupole concept with vertical split; Quadrupole has a conduction cooling from LHe supply pipe; Quadrupole mounted around beam pipe outside of the clean room; BPM has tight connection with quadrupole; Quadrupole bolted to the strong 300 mm diameter He gas return pipe; Special attention paid on the magnet assembly and mounting tolerances; Current leads also conductively cooled; Magnet cooling down time ~ 38 Hours; The Quadrupole model with split should be built and tested to verify the design.