Meeting summary on PIMS construction, CERN, 3d December 2009

present: W. Behr (FZJ), P. Bourquin, G. Favre, J-M. Geisser, L. Gentini, F. Gerigk, J. Kopec (IPJ), S. Mathot, M. Pap (FZJ), M. Polini, T. Tardy, M. Vretenar

agenda:

1. Logistics and planning (presentation F. Gerigk)
2. Central Department of Technology at Jülich (presentation M. Pap)
3. The Soltan Institute for Nuclear Physics (presentation J. Kopec)
4. Technical discussion
5. Action List

Technical Discussion

Questions & answers:

• IPJ asked why the outer tolerances of the rings are so tight and how this can be achieved. Answer: The outer diameter is used as reference surface for the clamping of the structure, but it is clear that once the piece is machined and taken out of the machine it will longer be within the -+ 10 um tolerance. The idea is to achieve on the machine a tolerance of -+ 10 um and it is only required on 2 "stripes" which make the connection to the neighbouring pieces. When the rings are assembled with the discs a clamping ring is used to put the rings into their correct shape. Once the ring is between 2 discs, the clamping ring can be removed and the next ring can be added. An open question is how to define an acceptance criteria for the delivery to CERN (see action list).
• FZJ asked whether a welding/welder qualification is necessary. Answer: FZJ is already qualified according to ISO standards. For the construction of the PIMS, CERN will put together a list of preparatory welding tests, which should be done before the series production. If the analysis of these tests is satisfactory, no further qualification will be needed.
• FZJ asked if the welds need to X-ray tested. Answer: the first weldings and then between 5 and 10% of the port weldings should be x-rayed. In case the FZJ X-ray machine is not powerful enough, IPJ can do the tests.
• How will the contracts be made: If we can show to the CERN management that it is financially advantageous to work with IPJ and FZJ on the construction of the PIMS, CERN can make a collaboration agreement with IPJ and FZJ. This will come as a general MoU with addenda specifying the contributions, payment, and planning details. The paperwork for this agreement can start once we have the complete cost numbers.

Statements:

• CERN: The final machining of all pieces is only done after the welding of ports and plugs. After joining the discs and rings via EBW, no further machinin operation is foreseen.
• IPJ: The metrology lab at IPJ should be operational by mid-2010.
• FZJ: FZJ has a metrology lab, which could be used for measurements, if the IPJ metrology is not ready (availability would have to be discussed),
• all brazing joints must be leak tested separately,
• 2 sets of tools are needed for leak testing of the port weldings: one at FZJ directly after the welding (this tool should be made at IPJ), one to be used at IPJ after the machining of the welding (to be given to IPJ by CERN),
• the tools for the port weldings can be made available to FZJ in February 2010,
• IPJ: in case there is a time problem for the machining of the pieces at IPJ, IPJ will be responsible to look for subcontractors,
• When the ports are welded, the rings are only rough machined. The fine machining is done after the welding of the ports.
• FZJ: the total number of weldings foreseen (per cavity) is: 24 plugs (4 x 6 discs), 6 tuner ports, 2 pick-up ports,
• the total number of cavities to be constructed is 12. Each cavity will increase in length but the dimensions of the plugs, beam pipe ports, tuner and RF pick-up ports will remain constant. Most likely also the shape of the discs will remain constant with the exception of the noses in the central cell.
• FZJ: in case the central disc cannot be brazed at IPJ, FZJ has a brazing oven that is large enough.
• FZJ: is working closely with Aachen University and in case of illness of a welder, replacements could be hired from Aachen,

Action List

-- FrankGerigk - 03-Dec-2009