Cavity Fabrication in Pilot Plant at KEK Y. Ajima, K. Enami, H. Hayano, H. Inoue, E. Kako, S. Noguchi, T. Saeki, S. Satoh, T. Shishido, A. Terashima, N. Toge, K. Ueno, K. Watanabe, Y. Watanabe, S. Yamaguchi, A. Yamamoto, Y. Yamamoto, K. Yokoya (KEK) N. Kawabata, H. Nakamura, K. Nohara, M. Shinohara (Shinohara Press Service Co. Ltd.) 28 Feb. – 3 Mar TTC Milano

ILC Test Facilities at KEK KEK つくばキャンパス（北側上空より） STF ATF/ATF2 Pilot plant for industrialization

Drawing of the pilot plant for industrialization at KEK EBW machine will be delivered at the end of FY2010 (March 2011). Deep-drawing machine was delivered in march Chemical Pilish (CP) room will be installed in march 2011 Trimming machine was delivered in march 2010.

Activities / schedule at Pilot Plant STF-Baseline 9-cell cavity with HOM Items 2010 Jan- 11 Feb- 11 Mar-11Apr-11 May- 11 Jun- 11 Jul- 11 Aug- 11 Sep- 11 Oct-11 Fabrication of KEK cell cavity w/o HOM Deep-drawing Trimming Center-cell half-cup Dumb-bells EBW Equato r EBW End-group Fabrication Complet e EBW machine in Pilot Plant Acceptance test at SST Deliver y to KEK Install ation Commisionin g EBW for end-group EBW for cavity fabrication Fabrication of KEK cell cavity w/ HOM Study on end-group fabrication method Collaboration with Shinohara Press Service Co. Ltd. Center- cell Deep- drawing Trimming End-group Fabrication with HOM

Fabrication of 9-cell cavity w/o HOM (KEK-01) Items 2010 Jan- 11 Feb- 11 Mar-11Apr-11 May- 11 Jun- 11 Jul- 11 Aug- 11 Sep- 11 Oct- 11 Fabrication of KEK cell cavity w/o HOM Deep-drawing Trimming Center-cell half-cup Dumb-bells EBW Equato r EBW End-group Fabrication Complete EBW machine in Pilot Plant Acceptance test at SST Deliver y to KEK Install ation Commisioni ng EBW for end- group EBW for cavity fabrication Fabrication of KEK cell cavity w/ HOM Study on end-group fabrication method Collaboration with Shinohara Press Service Co. Ltd. Center- cell Deep- drawing Trimming End-group Fabrication with HOM 1) Started the fabrication of 9-cell cavity w/o HOM (KEK-01, in STF-Baseline design) from last summer (2010). 2) EBW in a job shop (Tosei Electrobeam Co. Ltd.). 3) The 1 st 9-cell cavity (KEK-01) w/o HOM will be finished in summer 2011.

Deep-drawing of center-cell half-cups at Pilot Plant (September – November 2010) 26 center-cell half-cups had been deep-drawn and been trimmed. Trimming shape: Iris: butt-joint shape, Equator: step-joint shape Press machine with servo-motor controller at Pilot Plant

EBW of Dumb-bell at Tosei Electronbeam Co. Ltd. (December 2010 – February 2011) 13 dumb-bells had been made. 5 of them will be used for the test EBW of equator. 8 of them will be used for the fabrication of 9-cell cavity w/o HOM (KEK-01). EBW at the iris of dumb-bell at a job shop (Tosei Electronbeam Co. Ltd.)

Welding speed: 10mm/sec Parameter for EBW at iris Beam Current (mA) Rotation angle (degree) Both slope-in and slope-out have 2 steps to soften the slopes. Parameter used for EBW at iris: V = 120 kV, IB = 39 – 37.5 mA, Oscillation with dia. = 3.0 mm at 1 kHz Slope-out area is smooth for all dumb-bells. But we had small bump at the slope-in area in two dumb-bells. We need more study on the slope-in parameter.

Status of EBW machine for Pilot Plant Items 2010 Jan- 11 Feb- 11 Mar-11Apr-11 May- 11 Jun- 11 Jul-11 Aug- 11 Sep- 11 Oct- 11 Fabrication of KEK cell cavity w/o HOM Deep-drawing Trimming Center-cell half-cup Dumb-bells EBW Equato r EBW End-group Fabrication Complete EBW machine in Pilot Plant Acceptance test at SST Deliver y to KEK Install ation Commisioni ng EBW for end- group EBW for cavity fabrication Fabrication of KEK cell cavity w/ HOM Study on end-group fabrication method Collaboration with Shinohara Press Service Co. Ltd. Center- cell Deep- drawing Trimming End-group Fabrication with HOM 1) Acceptance test of EBW machine was done at SST factory (24 Jan – 4 Feb 2011). 2) EBW machine will be delivered at KEK on 31 st March ) Installation from beginning of April to end of April ) Commissioning in May – June Start using EBW machine for the fabrication of EBW.

Steigerwald Strahltechnik GmbH (SST) Factory Munich, Germany, 24 th Jan – 4 th Feb 2011 Acceptance test of EBW machine was successfully done at SST factory

Vacuum chamber Gun in vertical position Operator Steigerwald Strahltechnik GmbH (SST) Factory Munich, Germany, 24 th Jan – 4 th Feb 2011

Vacuum chamber, detachable wall panels (stainless steel) on inside wall 3.2m (length) x 1.5m (width) x 2.2m (height) Movable table Movable range: 1.5m (X) x 0.8m (Y) Position repeatability: mm Speed range: 0.3 – 100 mm/s A hole for electron beam Steigerwald Strahltechnik GmbH (SST) Factory Munich, Germany, 24 th Jan – 4 th Feb 2011

Cryo-pump PolyCold Screw Pump Steigerwald Strahltechnik GmbH (SST) Factory Munich, Germany, 24 th Jan – 4 th Feb 2011

Poly Cold ＋ Cryo-pump Poly Cold Steigerwald Strahltechnik GmbH (SST) Factory Munich, Germany, 2 nd Feb 2011 Acceptance test of vacuum chamber and pumping system

Beam operation and Z-movement of Gun were OK in horizontal position. Gun is movable on Z axis Movable range: 1.0m (Z) Position repeatability: mm Speed range: 1.0 – 30 mm/s Steigerwald Strahltechnik GmbH (SST) Factory Munich, Germany, 4 th Feb 2011 Acceptance test for the replacement of gun position (vertical to horizontal).

Fabrication of 9-cell cavity w/ HOM (KEK-02) Items 2010 Jan- 11 Feb- 11 Mar-11Apr-11 May- 11 Jun- 11 Jul-11 Aug- 11 Sep- 11 Oct- 11 Fabrication of KEK cell cavity w/o HOM Deep-drawing Trimming Center-cell half-cup Dumb-bells EBW Equato r EBW End-group Fabrication Complet e EBW machine Delivery and installation Acceptance test Deliver y to KEK Install ation Commisioni ng EBW for end- group EBW for cavity fabrication Fabrication of KEK cell cavity w/ HOM Study on end-group fabrication method Collaboration with Shinohara Press Service Co. Ltd. Center- cell Deep- drawing Trimming End-group Fabrication with HOM 1) Started end-group fabrication study from summer 2010 in collaboration with Shinohara Press Service Co. Ltd. 2) Plan is to start the fabrication of 9-cell cavity with HOM (KEK-02, in STF- Baseline design) from summer 2011 with EBW machine in the Pilot Plant.

Subject ： Plane anisotropy is unexpectedly enormous which causes the large difference of lower and upper ear heights. This might be improved in the future, otherwise it might cause a problem in yield rate of valued Nb material in deep-drawing as well. This collaboration started in September mm thick Nb material sheet is used to investigate the advanced deep-drawing technology for the mass production of HOM-can. The required drawing ratio (blank diameter / punch diameter) and drawing height are tentatively attained with above Nb sheet. Innovative deep-drawing research work in collaboration with Shinohara Press Service Co. Ltd. Lower ear height Upper ear height Nb (thickness of 1.5 mm) Inside of deep-drawn cup Punch diameter = 40 mm Deep-drawing by single press- forming process

HOM 管目標 域 ビームパイプ目標域 真円ブランク 異形ブランク Innovative ultra-deep-drawing technology with Nb material Figure shows “Deep-drawing height vs. Nb-blank diameter”. Average thickness reduction ratio ｜ τ ｜ =0.1, Punch diameter D p =40mm, (with rolled material; material thickness = 1.5 mm) Advanced press forming + die + Non-circle Nb blank Advanced press forming + advanced die + non-circle shaped Nb blank Conventional press forming Enough deep-drawing height was successfully achieved for HOM- can by single press-process. Future plan: ① Because there is the large anisotropy of supplied material in plane/normal direction, the development of method to apply uniform press-forming force to material is necessary. ② Searching of optimum and more stable parameter sets, and resultant deeper drawing height. Upper ear height Lower ear height H ＝ D p {(D 0 /D p )^2/(1-|τ|)-1}/4 Calculation of drawing height, H Circle-shaped Nb-blank Non-Circle shaped Nb-blank Nb-Blank diameter (mm) Deep-drawing height (mm) Deep-drawing by single press-process It is quite impossible to produce HOM- can and beam-pipe by single press- process if conventional press forming method is applied. Beam-pipe target area HOM-can target area

HOM-can: Protrusion Press forming Study was conducted on the protrusion press forming with 2.8mm thick Nb disk. Possibility of appropriate die structure and press forming process is obtained. Protrusion dimension: Diameter 10 mm x height 6 mm. Using a deep-drawn Nb HOM-can (thickness of 1.5 mm), the test of protrusion press forming was done. The picture shows the HOM-cans before and after the protrusion press forming. A protrusion was formed on the flat-bottomed surface. Future plan ： Study on the effect of work-hardening during the ultra deep-drawing of HOM-can on protrusion forming and also the achievement of more flatness accuracy and tolerance on both protrusion and flat-bottomed surface of HOM-can.

Simulation on production of HOM- antenna by press forming Future plan ： ① Production of a trial die and selection of appropriate press- machine. ② Study on blanking process of pre-product for forging. ③ Study on forging lubricant Simulation work is done for the“Cold Forging”of HOM antenna. Formability, optimum pre-product shape/size, die structure, forging force, etc. are studied using simulation software associated with plastic deformation. As a result, proper parameters are approximately fixed. Non-contact area with die Contact area with die Clamp in Z-direction Sideways drawingUnderways drawing Die Distribution of die-contact area at lower dead point 1 st step : Blanking of Nb plate + 2 nd step: Cold forging This simulation study is for 2 nd step.

Summary Fabrication of 9-cell cavity without HOM (KEK-01, STF-Baseline design) is ongoing. 13 dumb-bells for KEK-01 was fabricated with a press machine in the pilot plant and an EBW machine in the job shop (Tosei Electrobeam). Acceptance test of EBW machine for the pilot plant had been done in SST factory in Jan – Feb EBW machine will be delivered in KEK on 31 st March Plan is installation in April 2011 and commissioning in June – July Studies of end-group fabrication with HOM are ongoing in collaboration with Shinohara Press Service Co. Ltd. Fabrication of 9-cell cavity with HOM (KEK-02, STF-Baseline design) will start in summer 2011 with new EBW machine in the pilot plant.

Backup

Machines for cavity fabrication will be installed into one building. Clean environment, inspection machines, CP room will be provided. EBW machine will be delivered in march 2011, and all other machine will be delivered in march cavities on the plat-form Electron gun Plan of the pilot plant (KEK) for industrialization Example picture: EBW machine used for LL-cavity fabrication (Kuroki corp.) An image of the cavity industrialization Commissioning plan : Commissioning of machines except EBW to fabricate one cavity Commissioning of EBW machine to fabrication a few cavities R&D of cavity industrialization Example picture: LL cavity fabrication (Kuroki corp.)