1. PASI OsC meeting 12th July 2012
RFQ Manufacturing by
Peter Savage
PASI OsC meeting 12th July 2012

2. The FETS RFQ
3MeV
65keV
The FETS RFQ Physics simulations (frequency modelling and particle tracking) were complete in September 2011.
The Engineering Design was complete at the same time due to our design method used – splitting particle tracking from the bulk structure.
Then entered into the design for manufacturing phase and started the search for a suitable manufacturer.

3. Design for manufacture
What does this mean?
The 3D RFQ design was complete and the simulations showed the performance to be on specification.
Now the design had to incorporate features that would assist the following processes:
Manufacturing
Inspection
Lifting / Transportation
Assembly
Alignment
To achieve this we took feedback from the manufacturing and metrology functions and modified the design accordingly.
Design
Manufacture
Metrology

4. Manufacturer selection
With our complete design we visited manufacturers to describe the job and to see whether they were capable of producing the RFQ.
We needed a manufacturer with:
Experience – R&D
Equipment – scale, precision, axes and handling.
Reputation – to maintain.
Culture – work with the customer.
The current FETS team (excluding Alan) had not built an RFQ before and neither had the manufacturer so it was important to find a manufacturer with whom we could build a relationship to develop the production technique together.

5. Tolerancing and Datums
Defining the tolerances and datum system was a big challenge.
Balance between achieving the designed performance and being practical to manufacture.
Important to identify where tight tolerances were required and where we could be more relaxed. Again, the design system helped here where machining and assembly misalignments could be simulated.
Several iterations were required to discover ‘the’ datum system. It needed to be one simple elegant system that would be used during the four processes of:
Manufacture
Inspection
Assembly
Alignment
Degrees of freedom during assembly

6. What stage are we at now?
All 16 RFQ pieces have been machined to within 2.5mm of their final form (including all features).
The 4 pieces that make section 1 have are being finished on their outer faces now.
Once completed the datum dowel holes will be added before moving on to the vane side milling.
The trials are complete to perform the vane side milling operation and the surface finish has been approved..
The thread milling trials are complete.
CMM refurbishment at the manufacturer is underway.
The vane side milling is scheduled to begin on the week starting 23rd July.
Four vanes will be machined and inspected.
Delivery to RAL for stage 1 alignment following inspection approval.

7. Manufacturing Progress
JAN 2012
MARCH 2012
JULY 2012
MAY 2012

8. Bead pull / RF tests
We are preparing for bead pull and low power RF tests on the assembled RFQ section 1.
Goal is to measure the electric field to check for manufacturing and assembly symmetry and to aid tuning to achieve a flat longitudinal electric field.
Modification to existing bead-pull apparatus required.
Design of dedicated end flanges and coupling loops required.
RF Coupler
Bead pull / RF test end flange
Multi-axis bead-pull rig at RHUL

9. RFQ will be plumbed in to cooling manifold.
Ancillary components
The RFQ is often shown ‘naked’ for clarity but in reality it will be populated with dozens of assemblies for vacuum, tuning and cooling that will largely bury the copper structure.
The RFQ cooling manifold has been designed and is being assembled now. The cooling water supply will be installed in R8 immediately following the completion of the cladding work.
RFQ will be plumbed in to cooling manifold.
10 cooling circuits

10. Ancillary components
The completed assembly will then be vacuum tested before being approved ready for use.
Other ancillary components include:
Tuners assemblies
Cooling baffles
Pick-ups
End flange
End flange insert
The photo shows the current status of the production of the RFQ end flange assemblies. The next stage is to produce the stainless steel toroid covers before moving to vacuum brazing for the cooling channels.
Toroid cover

11. The FETS Supporting Infrastructure
The FETS CAD model shows the FETS beam-line sitting alone in R8 alone:
In reality the FETS will require supporting infrastructure that includes:
Concrete shielding for radiation safety including a personnel interlock system.
Waveguide and couplers to carry power from the Klystron to the RFQ and beyond to the MEBT.
Cooling systems – development work has started on the RFQ manifolds though cooling is required beyond the RFQ.
Power systems and control systems for diagnostics.
Vacuum systems with control.

12. Looking ahead
By the year end we hope to have one RFQ section assembled, commissioned and aligned on the FETS rail system.
In addition the remaining three RFQ sections will be manufactured and will be treated to the same commissioning processes as used for section 1.
In parallel to the RFQ work the MEBT design process is gathering momentum as you will hear next
Thank you.
any questions?