1. Hao Guo LINAC Department Institute of Modern Physics

2. 2 Introduction 1 Preparation 2 Assembly sequence 3 The problem in assembly process 4

3. 3  The demo of superconducting linac

4. 4  TCM1 The online test of TCM1The inner structure of TCM1

5. 5 The parts need assembly in clean room

6. 6 The parts need assembly in clean room include: HWR cavity Two SolenoidsBPM Coupler Two Valve and plate

7. 7 Changing room I ISO7 for ultrasonic clean ISO6 ISO5 for HPR control ISO5 for assembly and drying Air shower Changing room II ISO5 for strings assembly ISO6 for assembly and transition ISO7 for transition and vacuum leak check Outside The plan for clean room ISO5 for HPR ISO4 for parts drying

8. 8 Class 100 clean room Length: 6m Width: 3m Width of the door: 2m Approximate size of strings

9. 9 Assembly fixture

10. 10 Changing room I ISO7 ISO6 ISO5 Air shower Changing room II ISO5 for strings assembly ISO6 ISO7 ISO5 ISO4 Outside Entering route for fixture Cleaning outside surface by alcohol and non-woven fabrics first time Cleaning outside surface by alcohol and non-woven fabrics second time

11. 11 Changing room I ISO7 ISO6 ISO5 Air shower Changing room II ISO5 for strings assembly ISO6 ISO7 ISO5 ISO4 Outside Entering route for cavity Ultrasonic cleaning for 1h HPR Drying for 24h then sealing ports by plastic film Light BCP for 20~30min

12. 12 Changing room I ISO7 ISO6 ISO5 Air shower Changing room II ISO5 for strings assembly ISO6 ISO7 ISO5 ISO4 Outside Entering route for parts Drying for 24h then sealing ports by plastic film Solenoids, BPM, bellows, plates Ultrasonic cleaning for 1h with cleaning agent at 60 ℃ and rinsing by ultra-pure water (UPW)

13. 13 Changing room I ISO7 ISO6 ISO5 Air shower Changing room II ISO5 for strings assembly ISO6 ISO7 ISO5 ISO4 Outside Entering route for parts Drying for 24h screws, bolts, nuts, washers and gaskets Ultrasonic cleaning for 1h with cleaning agent at 60 ℃ and rinsing by ultra-pure water (gaskets was cleaned by acetone) Blowing them by high purity nitrogen and monitored by particle counter

14. 14 Changing room I ISO7 ISO6 ISO5 Air shower Changing room II ISO5 for strings assembly ISO6 ISO7 ISO5 ISO4 Outside Entering route for coupler Cleaning outside surface of couplers and test platform Coating bellow by plastic film then disassembling the coupler from test platform Cleaning the second time and coating bellow by plastic film again Bellow on coupler Test platform Disassembling inner and outer conductor Blowing inner and outer conductor by high purity nitrogen and monitored by particle counter

15. 15 Put parts on assembly fixture Remove plastic film on port Blow screws, bolts, nuts, washer, gasket or flange with high purity nitrogen Connect parts with bellow or directly Tight all screws to 30Nm The cleanliness maintenance of parts during assembly procedure: Every port of parts has been sealed by plastic film and the film will be removed when the port need assembly.

16. 16  The assembly sequence was from tow side to middle. The assembly sequence

17. 17  1 valves and plates to solenoids Valve plate Bellow Solenoid

18. 18  2 solenoid to BPM BPM solenoid

19. 19  3 blind flanges to cleaning ports and coupler port of cavity Four cleaning ports and one coupler port will be sealed by flanges

20. 20  4 coupler to coupler port of cavity The position of coupler The position of cavity

21. 21 The assembled strings

22. 22 Valve of strings Out side of clean room Class ISO7 clean room Class ISO5 clean room The schematic of leak check system Diaphragm valve Helium leak detectors Diaphragm valve dry vacuum pump Vacuum gauge Quadrupole mass spectrometer Molecular pump computer Fixture

23. 23

24. 24 Leak point at coupler flange Filled high purity nitrogen into strings Disassembled coupler from cavity Disassembled antenna form conductor Damaged the antenna on inner conductor Damaged the thread on inner conductor Tapping inner conductor again Cleaning the head of inner conductor by acetone

25. 25 1.The frequent failures of vacuum seal on cavity flanges Reason: a) The hardness of gaskets was higher than flanges. b) The nuts and bolts were made by the same material. 2. The failure of vacuum seal of coupler flange Reason: a) The nuts and bolt were made by the same material.

26. 26 Blind flange Aluminium-magnesium alloy gasket NbTi flange on cavity Vacuum sealing surface

27. 27 Flange Bolt size Number of bolts MaterialTreatment Tightening torque Scuffing torque DN40M88 304 stainless steel annealed25Nm DN25M66 304 stainless steel annealed20Nm15Nm The indentation of vacuum sealing surface after vacuum sealing indentation

28. 28 NameMaterialTreatmentBatchHardness (HBW) NbTi flange Niobium-Titanium Alloy 650 ℃ for 10h 182.8 Alloy Aluminium- Magnesium alloy- 5052 none57.1 gasket Aluminium- Magnesium alloy- 5052 none 1268.4 2179.2 3194.4 4241.2 Annealed57.35 (HV) Annealing process: The gaskets are annealed in vacuum annealing furnace. The temperature is up to 270 ℃ in 1h; keep warm for 90min; then cooling in furnace.

29. 29  The assembly process of TCM1 has been thought mainly reasonable.  Two reason may cause the field emission onset forward horizontal test compared with vertical test.  1. non-standard air-bleed process after the coupler leak at first time.  2. the phosphoric acid sticking on inner surface and dried after light BCP, meanwhile HPR was not able to clean them.

30. 30

31. 31  CM6 The design drawing of crymodule 6  CM6 will be assembled at the end of the year.

32. 32 The design drawing of CM6 strings

33. 33 Direction of strings assembly The brackets of solenoids are detachable. The brackets of coupler could be lift for 60mm.