Summary of the meeting at the Soltan Institute, 26-27 February 2008

place: Soltan Institute for Nuclear Physics (IPJ), Swierk, Poland

present: F. Gerigk, T. Kurtyka, T. Tardy, M. Vretenar (CERN), R. Kisiel, J. Kopec, J. Pracz, S. Wronka (IPJ)

Conclusions of the meeting (agreed by both sides)

Organisational structure of the manufacturing department within the Soltan Institute (IPJ):

The manufacturing department of the institute is financially independent and has to pay for its staff out of its own budget. It is also authorised to engage in manufacturing and selling of goods, which are not necessarily linked to the research in the institute. All machines, the workshop equipment, etc that is used by the manufacturing department is property of the Soltan Institute. For orders from hospitals or commercial institutions the name “HITEC” is used to represent the manufacturing department. Any surplus that is achieved will partly go into the budget of the Soltan institute, which will also carry possible financial losses.

Machining capabilities:

Presently IPJ is not equipped to do the machining (milling, turning, e-beam welding, metrology) in house. For a prototype these activities can be subcontracted to companies within Poland. For the series production it is expected that IPJ will upgrade its workshop with adequate equipment for milling, turning and measuring (metrology).

Electron-beam-welding:

It is proposed to subcontract the e-beam welding activities to the Institute for Vacuum Technology in Warsaw. The e-beam welding facilities in this institute comprise a 12 kW welding machine and a vacuum chamber with 70 x 84 x 160 cm. A larger chamber will be necessary for the welding of the PIMS, which can be obtained at a price of ~40 k¤ and a delivery time of ~3 months. This chamber would be ordered in case the contract for the PIMS is placed with IPJ. It was pointed out that the new chamber must be able to support the weight of a full cavity (~1 ton) plus the weight of the tooling. It was agreed that the machine needs to be tested to see if it is suitable. It was suggested by CERN to foresee cooling of the pieces during the welding operation to avoid excessive heating and a change of the welding parameters during the operation. This can be achieved by clamping aluminum cooling channels onto the structure. This technology can be developed together with CERN and it should avoid long cool-down periods, thus speeding up the production process. The vacuum tightness of the welds will be tested ideally after each welding process, or if sufficient after 2 or 3 subsequent welding operations.

Copper procurement:

2 options will be explored: i) IPJ will ask for an copper offer based on the size of the pre-machined pieces, which was used by CERN to obtain an offer from industry. IPJ will ask for pieces, which are not pre-machined, so that the first machining will be done at IPJ. The margins of the necessary excess material needed for the machining will be defined by IPJ. ii) CERN buys the copper based on a call for tender that was already launched.

Tuning:

it is foreseen to do the RF tuning of the structure at the Soltan institute (low-level RF measurements, cutting of fixed tuners). After the testing of a first prototype it will be decided if it is necessary to foresee a re-machining stage after the measurement of the clamped structure.

Technology transfer from CERN and Follow-up:

During all stages of finalising the mechanical design, machining and e-beam welding, and RF testing and tuning CERN will support IPJ. In practise this means that CERN experts will visit IPJ and vice versa.

Quality control:

vacuum tests and the leak tightness of the cooling channels will be done by IPJ, as well as a check of the geometric dimensions after machining. The results of these tests together with the results from low-level RF measurements after tuning of the structure will be made available to CERN in form of a certificate.

The next steps:

• IPJ will ask for an offer of OFE copper in the appropriate size, a document detailing the size of the necessary pre-machined pieces together with their number is attached,
• The linear welding test will be completed as soon as the welding machine is operational. The test piece will be brought to CERN at the beginning of April.
• A circular welding test will be prepared. IPJ will transmit the maximum size of the circular pieces to CERN and then CERN will provide a sketch for the welding to IPJ. IPJ will try to procure suitable rolled copper pieces for this test. In case there is problem CERN will be contacted and then CERN will provide the circular pieces and send them to Warsaw. The costs of the linear and circular tests will be covered by IPJ.
• CERN will work on the drawings for the hot prototype. It is expected that they are ready in May and they will then be discussed with IPJ. During the preparation of the drawings it may be useful for a mechanical expert from IPJ to come to CERN. Together with the drawings CERN will also make a cost estimate for production at CERN.
• After the circular welding test, a machining test is foreseen using the geometry of one to three actual accelerating cells. This is foreseen for May.
• At present it is foreseen to produce one prototype at CERN, and then a 2nd one at IPJ. They dimensions will be such that these prototypes can be used in Linac4 if they work as expected.
• Approximately 2 weeks before CERN starts measuring the cold model, it will contact IPJ, so that someone from IPJ can come to CERN for the measurements.

Finance & planning

• T. Kurtyka will start to draft a collaboration agreement,
• director of Soltan agrees that there is some preliminary money for people to visit CERN and to do some test pieces,
• CERN will prepare a price estimate. If IPJ is cheaper than that (by a certain margin), then it can be justified that the PIMS comes from Poland as an “in-kind” contribution, this way a call for tender will not be necessary,
• Depending on the results of the welding and machining tests and on further discussions with IPJ, CERN will decide on the possible construction of the PIMS at IPJ

Size of pre-machined copper pieces for the PIMS

Quantity	Dimensions (see drawings)						Description
	Length	A	B	C	D	inner/outer diameter
79	170	120	570	95	na	na	plates
27	160	120	570	na	120	na	end plates
46	320	na	na	na	na	475/570	body

-- FrankGerigk - 06 Mar 2008