2. RF QUALITY CONTROL AND CORRECTION DURING THE MANUFACTURING PROCESS OF THE SPL CAVITIES “DUMB-BELL TRIMMING” POA Meeting 11.03.15 Ercan Pilicer, Kai Papke, Sotirios Papadopoulos, Szabina Horvath-Mikulas

3. INTRODUCTION

4. DESIGN f π design Half-cell shape design: elliptical arc parameter optimization magnetic and electric boundaries L design |E| max i = |E| max j Magnetic Electric

5. DESIGN FREQUENCY f Pi half-cell (magnetic boundary at iris) f Pi dumb-bell f Pi cavity = = Sole resonator 1 frequency Doubly coupled resonator 2 frequencies Pi phase difference f 0, f Pi Fivefold coupled resonator 5 frequencies Pi/5 phase difference f 0, f Pi/5, f 2Pi/5, f 3Pi/5, f 4Pi/5, f Pi Monopole mode field distribution in each single component of the cavity sub-assemblies Simulation errors Predetermined ambient conditions: 20 degree Celsius Vacuum

6. MANUFACTURING PHASES TO CONTROL I.Half-cells II.Dumb-bells III.Final cavity @warm IV.Final cavity @cold

7. POSSIBLE CORRECTIONS I.Half-cells No possibility II.Dumb-bells Trimming III.Final cavity @warm Tuning machine IV.Final cavity @cold Cold tuner

8. REQUISITES I.Half-cells No possibility Acceptance II.Dumb-bells Trimming Cutting amount III.Final cavity @warm Tuning machine Amount for plastic deformation of the individual cells IV.Final cavity @cold Cold tuner Range for elastic deformation of the overall cavity

9. DUMB-BELL CORRECTION Length Frequency Initial state Target state

10. DUMB-BELL CORRECTION Length Frequency L measured f measured L target f target Initial state Target state

11. CORRECTION BY TRIMMING Length Frequency L measured f measured L target f target Initial state Target state Trimming Correction in 1 direction f↑ @ L↓ Trimming vector

12. TRIMMING OPTION 1 Length Frequency L measured f measured L target f target Initial state Target state Trim to the right length L trim Δf trim

13. TRIMMING OPTION 2 Length Frequency L measured f measured L target f target Initial state Target state L trim Trim to the right frequency Δf trim

14. Pushing vector CORRECTION BY TUNING Length Frequency L measured f measured L target f target Initial state Target state Tuning Correction in 2 directions Pulling: f↑ @ L↑ Pushing: f↓ @ L↓ Pulling vector

15. TRIMMING OPTION 3 Length Frequency L measured f measured L target f target Initial state Target state L trim Trim to an intermediate state Pre-tune by pulling L pull Δf trim Δf pull

16. TRIMMING OPTION 3 Length Frequency L measured f measured L target f target Initial state Target state L trim L pull Δf trim Δf pull

17. TRIMMING OPTION 3 Length L measured f measured L target f target Initial state Target state L trim Trim to an intermediate state Pre-tune by pushing L push Frequency Δf trim Δf push

18. TRIMMING OPTION 3 Length L measured f measured L target f target Initial state Target state L trim L push Frequency Δf trim Δf push

19. TRIMMING AND TUNING SENSITIVITIES Length Initial state Trimming sensitivity Tuning sensitivity Pulling Pushing Correction Lengths Calculation Frequency

20. TUNING MACHINE STATUS

21. TUNING MACHINE OVERVIEW

22. CAVITY SENSITIVITY FOR SHAPE OUTLINE IMPERFECTIONS -6 kHz/mm/mm 6 kHz/mm/mm0 kHz/mm/mm sensitivity in normal (out of the volume) direction sensitivity in longitudinal direction sensitivity in radial direction

23. REQUISITES I.Plastic Pi-mode frequency change OVER Plastic cell longitudinal displacement -> Tuning sensitivity for trimming (calculated for half-cells) II.System Limit -> Half-cell acceptance III.Elastic Pi-mode frequency change OVER Plastic Pi-mode frequency change (OR the correlation to the displacements) -> Tuning method (required Pi-mode frequency change per half-cell)

24. QUESTIONS I.Where to measure the displacement? -> Cell or cavity II.How does the field distribution influence the sensitivity? -> Field mapping III.Repeatability -> Cell dependence -> Cell initial state dependence -> Tuning cycle dependence IV.How equally the pressure is distributed along the cell circumference and how parallel the plates deform the cell?

25. PREVIOUS MECHANICAL SENSOR SYSTEM Pressure sensorDisplacement sensor

26. UPGRADED MECHANICAL SENSOR SYSTEM Strain gaugesDisplacement sensor

27. MECHANICAL TESTS

28. PREVIOUS MEASUREMENTS (OLD SYSTEM, BEFORE HEAT TREATMENT)

29. CERN SPL COPPER CAV2 CELL3&4 COMPRESSION AND TRACTION TEST

30. CERN SPL COPPER CAV2 CELL3 COMPRESSION AND TRACTION TEST Before and after heat treatment – released state

31. CERN SPL COPPER CAV2 CELL4 COMPRESSION AND TRACTION TEST Before and after heat treatment – released state

32. TO THE LIMIT FOR CELL4

33. TO THE LIMIT FOR CELL3

34. ELASTIC AND PLASTIC CORRELATION CELL3 AND CELL4

37. ELASTIC AND PLASTIC CORRELATION CELL3 AND CELL4 TO THE LIMITS

39. CELL3 STIFFNESS