Results of short module and qualification strategy PIMS production meeting 26-27 February 2013 Rolf Wegner

Production qualification, April 2012 Status of machining qualification, 19.04.2012: Step std + central disc end disc (cooling ch.) ring by milling ring by turning WG-ring 1st rough (+2mm) ok (10.01.2012) ok (19.04.2012) brazing test => horizontal or vertical brazing ? 2nd rough (+1mm) ok (30.03.2012) Ring G_13-14: serious non-conformities => repair of EB-weld Ring G_1-2: serious non-conformities => machining tests 3rd rough (+0.2mm), final Full Quality Assurance Report + check at CERN 26.02.2013 PIMS production meeting 26-27 February 2013 Rolf Wegner

Review of steps towards qualification Meeting at CERN in March 2012: * machining procedures optimised (=> clamping) [parts seen 5 to 10 times out of tolerance] * specifications very tight; small performance degradation <=> accepting certain deviations from specifications (EDMS 1209460) * recommendation: final machining on a lathe Meeting at NCBJ in April 2012: * green light for rough machining of discs for series * Quality Assurance Report form defined Mai 2012: * new weld qualification with cosmetic pass + repair of weld for ring G_13-14 * preliminary metrology end disc M_1 => green light to finish end disc M_14 and disc M_6-7 June 2012: * brazing test finished 26.02.2013 PIMS production meeting 26-27 February 2013 Rolf Wegner

Review of steps towards qualification July 2012: * QA report disc G_2-3 ok, end disc M_1 ok, shipment to CERN * QA report disc M_6-7, re-machining of assembly ø524 requested * QA report end disc M_14, agreed on adaptation of ring M_13-14 - side 14 for assembly ø524 September 2012: * welding of ring M_13-14 ok, defect on ring M_1-2 => sent for repair to Julich => using ring G_13-14 as 2nd ring for short module * brazing test evaluated at CERN (visual inspection, ultrasound & vacuum tests), very good result, => green light to produce waveguide ring cavity M * disc G_2-3, end disc M_1 inspected at CERN => green light for finishing all discs cavity M November 2012: * QA report ring M_13-14 26.02.2013 PIMS production meeting 26-27 February 2013 Rolf Wegner

Review of steps towards qualification December 2012: * QA report re-machined ring G_13-14 => green light for finishing all rings cavity M * end disc M_14, disc M_6-7, ring M_13-14 and ring G_13-14 arrived at CERN January 2013: * QA report discs M_2-3, M_12-13 February 2013: * QA report discs M_4-5, M_10-11 26.02.2013 PIMS production meeting 26-27 February 2013 Rolf Wegner

Quality Assurance Reports => "Disc G_2-3 - Analysis & Comparison CERN.xlsx" * report form from NCBJ exactly as desired * analysis to specifications * analysis to acceptable dimensions * comparison to CERN measurements metrology machine accuracy: ± 6 μm => comparison precision: ± 12 μm => specifications 500 mm ± 10 μm difficult to machine and difficult to measure !!! results quite similar (a few small points to discuss tomorrow) 26.02.2013 PIMS production meeting 26-27 February 2013 Rolf Wegner

PIMS production meeting 26-27 February 2013 Rolf Wegner Vacuum tests at CERN end discs M_1, M_14; disc G_2-3; ring M_13-14 all leak rate < 2*10-11 mbar*l/s 26.02.2013 PIMS production meeting 26-27 February 2013 Rolf Wegner

PIMS production meeting 26-27 February 2013 Rolf Wegner Brazing test at NCBJ good visual impression vacuum tight (leak rate <1*10^-10 mbar l/sec) good ultrasound analyse results Agostino: ”It is hard to do it better” => Green light for brazing of WG ring of 1st cavity (25.09.12) 26.02.2013 PIMS production meeting 26-27 February 2013 Rolf Wegner

Machined parts, end discs M_1 and M_14 element EDMS remarks slight deviations* serious deviations* where leak tight cavity suited end disc M_1 1243403 surf. roughness <0.8 Ø524: gap +16 μm cooling channels (wall >5.0mm) survey hole 1 8H7 8.37 mm but NCBJ and CERN metrology deviate ≤ 54 μm none CERN yes yes, ready end disc M_14 1253682 scratches, craters ⌾Ø518: +33 μm nose position: +10 μm Ø524: gap -31 μm => adjacent ring opened by 30 μm some holes too short (1.. 2 mm) ⌾Ø524: +74 μm tbd, * to acceptable dimensions 26.02.2013 PIMS production meeting 26-27 February 2013 Rolf Wegner

Machined parts, disc M_6-7 element EDMS remarks slight deviations* serious deviations* where leak tight cavity suited disc M_6-7 1253702 scratches, craters ⌾Ø518: +43 μm / +16 μm Ø524: gap -5 μm / 57 μm ⌾Ø524: +20 μm / 26 μm Ø538: +25 μm / + 23 μm nose length: -5 μm / +12 μm nose position: +19 μm / 35 μm coupling slot symmetry & R15 cooling channels (wall >5.0mm) surf. roughness nose cone 1.0 to 2.8 μm side 7 burrs on all cooling channels => to be re- machined CERN * to acceptable dimensions 26.02.2013 PIMS production meeting 26-27 February 2013 Rolf Wegner

Machined parts, ring M_13-14 element EDMS remarks slight deviations* serious deviations* where leak tight cavity suited ring M_13- 14 1252346 side 14 well opened for end disc M_14 circularity 0.04 / 0.08 with 2 max/min ⌾Ø538: +2 μm / +19 μm surf. roughness inside 1.4 μm => 1.2% more RF losses ⌾Ø524: +51 μm / +104 μm CERN YES tbd, ready * to acceptable dimensions 26.02.2013 PIMS production meeting 26-27 February 2013 Rolf Wegner

Machined parts, disc G_2-3 element EDMS remarks slight deviations* serious deviations* where leak tight cavity suited disc G_2-3 1243398 surf. roughness <0.8 Ø538: +23 μm / + 19 μm nose length: +18 μm flatness nose tip: 47 μm CERN YES YES, ready * to acceptable dimensions 26.02.2013 PIMS production meeting 26-27 February 2013 Rolf Wegner

Machined parts, ring G_13-14 element EDMS remarks slight deviations* serious deviations* where leak tight cavity suited ring G_13-14 1252344 machining tests many flatness @ welds: 87 μm / 75 μm B⊥A: 0.114 (0.3 all cavity) NCBJ no but ok for short module * to acceptable dimensions Ring G_13-14 was intended for machining tests to validate milling technology (spare material of CERN prototype) port welding defect, weld was repaired, further machining tests port welding defect of ring M_1-2, ring G_13-14 is used for assembly check of short module 26.02.2013 PIMS production meeting 26-27 February 2013 Rolf Wegner

Machined parts, summary discs analysed are close to acceptable dimensions => remarkable progress made since last year (improvement of factor 5 to 10 on most tolerances) assembly diameter 524.720-0.025+0 seem to be well under control (QA reports discs M_2-3, M_4-5, M_10-11, M_12-13) however, deviations on * coaxiality axis/524/538mm (=> inter-cavity alignment – aperture reduction) * perpendicularity axis/faces (=> inter-cavity alignment – aperture reduction) * cooling channel finishing => we need to analyse remaining discs of cavity M at CERN for qualification ring M_13-14 is close to acceptable dimensions => remarkable progress made since last year (machining procedures were developed [weld deformation] and most acceptable tolerances reached) assembly diameter 524.720+0.050+0.075 seem to be well under control (also ring G_13-14) however, deviations on * coaxiality 538/524mm (=> inter-cavity alignment – aperture reduction) * perpendicularity axis/faces (=> inter-cavity alignment – aperture reduction) * only 1 ring as sample => we need to analyse remaining rings of cavity M at CERN for qualification 26.02.2013 PIMS production meeting 26-27 February 2013 Rolf Wegner

Short module: assembly test end disc M_1 ring G_13-14 disc G_2-3 ring M_13-14 end disc M_14 assembly was very smooth only end disc M_14 was slightly difficult to place correctly, small gap remains => Thierry will use dense point weldings before final weld 26.02.2013 PIMS production meeting 26-27 February 2013 Rolf Wegner

Short module: RF check, preliminary results measured simulated freq. difference [kHz] ratio meas/sim [%] f_mode_1 [MHz] 349.756 350.500 -744 Q_mode_1 21'500 26'560 80.9 f_mode_2 [MHz] 363.308 363.970 -662 Q_mode_2 27'730 30'200 91.8 z-axis: assembly order z=0 end disc M_1 - ring G_13-14 - disc G_2-3 - ring M_13-14 - end disc M_14 … to z=max 26.02.2013 PIMS production meeting 26-27 February 2013 Rolf Wegner

Short module: RF check, preliminary results measured simulated freq. difference [kHz] ratio meas/sim [%] f_mode_1 [MHz] 349.756 350.500 -744 Q_mode_1 21'500 26'560 80.9 f_mode_2 [MHz] 363.308 363.970 -662 Q_mode_2 27'730 30'200 91.8 assembly had to be clamped, otherwise Q ~ 1'000, f_mode_1 ~ 349.200 MHz Q-values reasonable, will improve with welding (~ 10% seen for prototype) field profiles look very similar, slight deviations for mode 2 ~ 700 kHz frequency difference between measurement and simulations simulation uncertainty ~ ± 500 kHz (mesh limit, 2 cells, different geometry) tuning range (island + plunger) for mechanical tolerances + simulation uncertainties: ± 600 kHz => further analysis needed to understand difference in frequency simulations/measurement => simulation model needs to be checked carefully (systematic difference 700 kHz) 26.02.2013 PIMS production meeting 26-27 February 2013 Rolf Wegner

PIMS production meeting 26-27 February 2013 Rolf Wegner Next steps qualification of vacuum check * visit of NCBJ experts to CERN, March 25-26th, tests of end disc, disc, ring * shipment of equipment to NCBJ (~ 100 kg, ~ 200 pieces, ~ 25'000 CHF) * visit to NCBJ with CERN experts, intended before April 19th (material !) tests of end disc, disc, ring vacuum check of discs and rings cavity M at NCBJ production and checks of waveguide ring cavity M at NCBJ check of discs and rings cavity M at CERN => qualification for series production check of waveguide ring cavity M at CERN => qualification for series production in order to advance production, maybe intermediate green light for finishing cavity 2 26.02.2013 PIMS production meeting 26-27 February 2013 Rolf Wegner

Production qualification, February 2013 Status of qualifications, 25.02.2013: Step std + central discs end discs rings WG-rings 1st rough (+2mm) ok (10.01.2012) ok (19.04.2012) ok (25.09.2012) 2nd rough (+1mm) ok (30.03.2012) ok (18.12.2012) final for cavity 1 (M) (27.09.2012) (10.05.2012) final for cavity 2 vacuum check at NCBJ final for series check discs cavity 1 (M) at CERN check rings cavity 1 (M) at CERN check WG-ring cavity 1 (M) at CERN 26.02.2013 PIMS production meeting 26-27 February 2013 Rolf Wegner