Cryostat assembly, integration and commissioning procedures

1. Cryostat assembly, integration and commissioning procedures M.Olcese Version: 07 May 2008

2. Definitions • Flanges/plates (from innermost): • MC plate: mixing chamber plate • HEX plate: heat exchanger plate • STILL plate • 4K flange: Inner Vacuum Chamber (IVC) plate • 40K plate • 300K flange: Outer Vacuum Chamber (OVC) plate • Vessels/screens: • MC screen (upper and lower part) • HEX screen • 4K vessel: IVC vessel • 40K screen • 300K vessel: OVC vessel

3. Schematic: cryostat 300K, 4K flanges and 40K plate 300K, 4K vessels and 40K screen STILL top lead ring STILL plate Internal top lead shield HEX and MC plates Detector support plate Lateral STILL lead shield Detector Internal screens (STILL-HEX-MC) Lateral STILL lead shield support cradle Main external shielding

4. Schematic: building and platform 2° floor 1° floor Concrete walls Corridor side Parking Side of main shielding Main rail system Light platform Main platform (upper) Main platform (lower) Aux. rail system

5. Scenarios • Initial installation: 1.1 Installation of 300k-40k-4k plates 1.2 Dry fit of vessels and screens 1.3 Installation of STILL-HEX-MC plates • Cryostat commissioning • Detector installation • Access for maintenance

6. General issues • All the individual items (with few exceptions) can be brought on the main platform for the installation: • from the hut ground floor with the platform in the side position • Directly from the external corridor using an auxiliary rail system

7. 1 Initial installation1.1 installation of top plates/flanges • The plates are delivered clean and inside plastic bags • The plates are piled up on the main platform (a platform add-on may be required to reach the 1° floor level) • The main platform is raised • Eye bolts + radial extensions (if needed) will be fixed to the plates. • The plates are lifted by means of the hoist cable system and connected to the tie rods/suspensions • It may be convenient to install, along with the plates, some of the internal components like: sections of the source tube, wire feed-throughs, IVC pumping tube, …

8. Initial installation 1.1: setting of plates on platform at ground level Option 1 Stack of plates in reverse order (4K-40K-300K) Platform extension Main platform

9. Initial installation 1.1: setting of plates on platform at ground level Option 2 Plates set on auxiliary platform from the corridor side

10. Initial installation 1.1: platform with plates ready for lifting

11. Initial installation 1.1: platform reach the 1° floor level

12. Initial installation 1.1: 300K-4K flanges and 4K plate are installed in sequence

13. Initial installation 1.1: completed

14. 1 Initial installation1.2 dry-fit of 300K-4K vessels and 40K screen • Purpose: • check the handling procedure and sign-off of the cable hoist system • Check vacuum tightness and deformations of OVC and IVC Issues/comments: • The internal screens (still, HEX, MC) must be installed in clean conditions, so they will not be installed in this phase through the floor opening. They will be installed and removed from the clean room at the end of the dry fit • All the screens/vessels are delivered in upright position on a basement

15. Initial installation 1.2: 4K (40K, 300K) vessel set on platform Option1 Option2

16. Initial installation 1.2: 4K (40K, 300K) vessel ready for lifting Lifting cables Lifting ears and eye bolts are installed and hoist cables connected

17. Initial installation 1.2: 4K (40K, 300K) vessel lifted and fixed to the 4K flange

18. Initial installation 1.2: testing • Leak tightness • Vacuum • Deformations

19. 1 Initial installation1.3 Installation of STILL-HEX-MC plates

20. Initial installation 1.3: installation of temporary support structure The main platform is moved aside

21. Initial installation 1.3: 300K-40K-4K vessels lowered down

22. Initial installation 1.3: the floor is closed and sealed off From this moment on the area around the cryostat will have to be kept clean at all time

23. Initial installation 1.3: installation of the STILL plate

24. Initial installation 1.3: installation of the STILL plate

25. Initial installation 1.3: installation of the HEX and MC plates

26. Initial installation 1.3: installation of the HEX and MC plates

27. 2. Cryostat commissioning • 2.1 integration of all the internal components (DU, pulse tubes, wire inserts, source guiding tubes, suspensions) • Preliminary cooling tests and functional tests of all components • 2.2 installation of STILL lateral lead shield • 2.3 installation of the internal top lead shield and dummy detector (DD) • alignment and calibration of the detector suspension system • 2.4 Final tests • COMMENTS: • The 2.1 phase will last for quite some time and will require several openings and closings of the cryostat: it is recommended to use a temporary support structure on the main platform to store the screens/vessels. This would allow the assembly of the main external shielding in parallel and off-line • In phase 2.1 not all the screens/vessels may be needed for the tests: those internal are stored on the first floor and could be installed when needed independently from the external ones

28. 2. Cryostat commissioning 2.1 integration of all the internal components (DU, pulse tubes, wire inserts, source guiding tubes, suspensions)

29. Cryostat commissioning 2.1: installation of internal components In parallel: assembly of main shielding

30. Cryostat commissioning 2.1: installation of internal screens (1)

31. Cryostat commissioning 2.1: installation of internal screens (2)

32. Cryostat commissioning 2.1: installation of internal screens (3) Screens lifted by the cable hoist system or by hydraulic jacks

33. Cryostat commissioning 2.1: installation of external vessels (1)

34. Cryostat commissioning 2.1: installation of external vessels (2) main shielding completed

35. Cryostat commissioning 2.1: cold tests

36. Cryostat commissioning 2.1: cold tests • During testing: • The temporary support is removed

37. Cryostat commissioning 2.1: cold tests • During testing: • The platform with the main shielding is brought on-axis

38. 2. Cryostat commissioning 2.2 installation of STILL lateral lead shield

39. Cryostat commissioning 2.2: preparation for installation of STILL lateral lead shield (1) The floor is opened

40. Cryostat commissioning 2.2: preparation for installation of STILL lateral lead shield (2) The 4K-40K-300K vessels are lowered into the main shield

41. Cryostat commissioning 2.2: preparation for installation of STILL lateral lead shield (3) • Floor closed • External vessels sealed off

42. Cryostat commissioning 2.2: preparation for installation of STILL lateral lead shield (4) Removal of internal screens

43. Cryostat commissioning 2.2: preparation for installation of STILL lateral lead shield (5) Removal of internal screens

44. Cryostat commissioning 2.2: preparation for installation of STILL lateral lead shield (6) Main shielding moved aside

45. Cryostat commissioning 2.2: preparation for installation of STILL lateral lead shield (7) Temporary support added on main platform

46. Cryostat commissioning 2.2: preparation for installation of STILL lateral lead shield (8) Platform raised and sealed

47. Cryostat commissioning 2.2: preparation for installation of STILL lateral lead shield (9) • Floor opened • Temporary support raised to reach floor level

48. Cryostat commissioning 2.2: installation of STILL lateral lead shield (1) Still lead cradle set on support

49. Cryostat commissioning 2.2: installation of STILL lateral lead shield (2) Platform lowered

50. Cryostat commissioning 2.2: installation of STILL lateral lead shield (3) Bottom lead layer and first ring added