1. ESS MEBT Quadrupole magnets
J.L. Muñoz
Bilbao, 27 March 2019

2. ESS MEBT Quads – Bilbao, 27 March 2019
Contents
Quads requirements and specifications
Tender/fabrication process review
Design details
Magnets characterization
Box Incident
Power supplies
Some simulations
Conclusions
ESS MEBT Quads – Bilbao, 27 March 2019

3. MEBT line includes 11 quadrupole magnets, with integrated dipolar correctors
All magnets share the same design and are identical, although operating gradients and F/D characteristics depend on position in line

4. Quadrupole magnets requirements
Relevant documents in CHESS:
MEBT Quadrupole magnet TDR
Quad main drawing
Quads DOORS L4 check
Characterization of pre-series magnet

5. Tender and contract timeline
24Feb2016: PDR at Bilbao.
Preliminar design presented
Comments and improvements noted
19Sep2016: Tender process launched
Based on PDR design + L4 + improvements
1+10, pre-series thorough characterization
13Feb2017: Contract awarded to Danfysik
25Apr2017: Kick-off meeting (admn. delays)
01Jun2017: PDR #1 (based on 3D model)
14Jun2017: PDR #2 (based on 3D model). PASSED.

6. Tender and contract timeline
01Ago2017: First set of documentation for FDR (drawings, assembly prodecures, cable sketches)
06Oct2017: Final set of documentaion for FDR
17Oct2017: FDR PASSED, with actions open
08Feb2018: First measurements of pre-series magnet
Concerns on: Center-height of magnet (corrected)
Mechanical-magnetic axis offset
16Apr2018: All measurements of pre-series magnet accepted, magnet sent to ESS-Bilbao premises.
02May2018: Pre-series magnet arrives at ESS-Bilbao (magnet 1/11)

7. Tender and contract timeline
11May2018: Local tests ran, report issued
Visual inspection issues (labels, weldings)
IP2X cover
Magnet accepted with minor corrections for series
03Oct2018: Fabrication and tests for next set of 4 magnets, delivery after data package is accepted.
11Oct2018: Reception of 4 magnets (2-5/11)
08Nov2018: Incident with transport of remaining magnets. New assembly, tests and correction actions
14Dec2018: Final data package for incident magnets
21Dec2018: Magnets arrive to ESS-Bilbao (6-11/11)

8. Tender and contract timeline
(Data package)

9. Design details

10. Design details
Pole tip design

11. Design details
Coils

12. Design details
Coils

13. Design details
Mechanical

14. Design details
Mechanical
(Industeel XC-06)

15. Design details
Mechanical

16. Design details
Mechanical

17. Characterization Documentation available for all magnets
More than 600 files and 600 Mb of data

18. Pre-series magnet
Tests done at Danfysik

19. Pre-series magnet
Dimensional check

20. Pre-series magnet Thermo-switches tests (2 per coil) All coils tested:
Dimensional control, resistance, insulation
Before and after impregnation
Pdf docs of all tests documents sent

21. Pre-series magnet
After opening+assembly (3 times)

22. Pre-series magnet Complete magnet test document
Visual inspection (paint, brazing, screws,photo)
Dimensions
Coil numbering
Dissasembly/assembly test
Resistance, insulation, hydraulic leak
Full power test (250A+steerers 6.6A, during 1 hour)

23. Pre-series magnet
Complete magnet test document

24. Pre-series magnet
Target position and mech-mag offset doc

25. Pre-series magnet Target position and mech-mag offset doc
“Resistance based” measurements:
Offset is measured in the SW bench
First, magnetic center is found
Then wire is moved in X and Y steps until electric contact is detected
This measures mechanical aperture
Process is repeated for all poles, and overall offset computed

26. Pre-series magnet
Excitation curve measured with Hall probe

27. Magnetic measurements
Integrated gradient and hamonics
Measured with SSW device, rotating a wire in a 19.5 mm radius circle, evaluating at 15.0 mm radius
Higher order harmonics are measured for different quadrupolar and dipolar coils excitation
Excel files of all measurements provided

28. Magnetic measurements
Summary of results, extracted from raw data

29. Magnetic measurements
Summary of harmonics measured at I=10A (L4<1 %)

30. Magnetic measurements
Summary of harmonics at I=250A (L4 < 1%)

31. Additional tests
Local tests: one of the magnets was measured in CFAA (UPV/EHU) facility
(Model built with poles interpolated from metrology)

32. Box incident
On 1/11/18 Danfysik reported an incident with the box containing the last batch of six magnets

33. Box incident
The box contained magnets numbered 17034, 17035, 17036, 17040, and
A comparison of measurements (pole gap and shoulder) after reassembly was done.
Problems (values worse than previous ones) found in three magnets (17035, and ). In particular, magnet presented values which are outside the required tolerances according to magnet specification.
Magnet stands were also slightly bent from the laterals. Danfysik pointed out that this could be corrected when bolting the stand to the magnet support, straightening the stand this way.

34. Box incident The strategy that was devised to cope with this was to:
1. Start with the operation of opening/closing of the magnet.
2. Repeat all complete measurements of the magnets.
3. Deliver an updated complete data package for each magnet.
ESS (JS) was informed and participated in all Skype meetings between ESS-Bilbao and Danfysik

35. Box incident
17034
17035
17036
17040
17043
17044
Just after box incident
Before opening
After opening
After 1st opening
After 2nd opening
time

36. Box incident
Some correction was needed for magnet # The foot was re-machined and this has corrected the mechanical problems.
After receiving all mechanical and magnetic measurements, we have found that all magnets are within specifications and that there is no significant difference between magnets before and after the incident.
Anyway, this delayed quite a bit the magnets delivery to Bilbao

37. Simulations
Extensive simulations activities have also been done

38. Power Supplies

39. Conclusions 11 magnets were build and tested
All magnets are within L4 requirements
All mechanical restrictions (BPM, length, etc) are also met
Fabrication has suffered several delays and incidents
All the documentation has been collected and sent