超伝導加速空洞の製作技術と計測技術（講義1/3）
OHO06 (KEK)佐伯 学行

Cavity fabrication and preparation sequences
for the TESLA / TTF cavities at DESY
1st ILC workshop at KEK Tsukuba Japan
A.Matheisenfor DESY and the TESLA Collaboration

TESLA型 9セル空洞
アイリス径 70 mm

9-cell ICHIRO high-gradient
Low-Loss (LL) cavity
Hp/Eacc = 36 Oe/(MV/m)

Our goal is 51 MV/m !
(45 MV/m in operation)(Designed at KEK incollaboration with DESY.)

Most famous Japanese
baseball-player.

アイリス径 60 mm
Record breaker, 262 hits
in single season in 2004.

STF Phase 1Details of STF phase 1, 2=>Talk (ThA01) by Hayano

TESLA design cavities
Operation at 35 MV/m

Four 9-cell ICHIRO LL cavities

Operation at 45 MV/m

Already delivered to KEK !

イチロー9セル空洞 4本分のニオブ材料

ビームパイプ

セル部

高調波用アンテナ

Overview over cavity fabrication

Cavity(9 cell TESLA /TTF design)

Cavity(9 Zeller)

HantelEndhalbzellEndrohr- Einheit
kurz

Dumb-bellEndhalbzellEndrohr- Einheit
lang

End group 1

End group 2

Stützring

NormalhalbZelle

NormalhalbZelle

Endhalbzellekurz
Anbindung(end-kurz-lang)

Nb-BlechNormalhalelleHauptkopplerstutzen

Endrohrkurz

Flansch(Endflansch)

HOM-Koppler
kurze Seite

Flansch(HauptkopplerStutzen)

Rippe

Rippe

Flansch(end-kurz-lang)Bordscheibe
lange Seite

Flansch(Endflansch)

Endhalbzellelang

HOM-Koppler
lange Seite

Antennenstutzen
lang

Endrohrlang

Nb-BlechNormalhalbzelle
HOM-Koppler
DESY
End-kurz-langFormteil F

Antennenflansch
NW 12

Antennenflansch
NW 12

HOM-Koppler
DESY
End-kurz-langFormteil F
langOverview over cavity fabrication

Cavity(9 Zeller)

Hanteldumb bell

Stützring

NormalhalbZelle

Nb-BlechNormalhalelle

NormalhalbZelle

Nb-BlechNormalhalbzelle

Cavity(9 Zeller)

Fabrication of ICHIRO Cavity at KEK(1)Pressing Nb plate

56 half-cells were pressed in a few hours

21 February 2005

Fabrication of ICHIRO Cavity at KEK(2)TrimmingTrimming

After trimming

Elongation Measurement

Elongation

50%

+

周方向
半径方向
20%

--20%

Electron Beam Welding (EBW) MachineElectron Beam Welding (EBW) MachineElectron GunOperator

Electron Beam Welding (EBW) parameter search

Beam-parameter search with Nb test-pieces.
Oscillation of beam was applied.

150 kV, 30 mA, 10 mm/s
30mA
28mA

15 deg180 deg360+15+23 deg

Beam

35 degree

Inside, EBW depth = 40%(10% overlap)
150kV, 10mA, 10 mm/s
Cooling 5 min. => 45 C

Beam

EBW of Dumbbell
BeamDumbbell

Outside, EBW depth = 70%
150kV, 18 mA, 10 mm/s

Stiffener-ring
Jig

Stiffener
Ring

Jig

Dumbbell withstiffener-ringafter EBW.

Jig

Pull

Jig

3-Dimensional Measurement
MachineDumbbell-height measurement and tuning
Dumbbell heightafter EBW, without stiffener

1 mm8N=217

design value=115.864(included EBW shrinkage
eqator*2=0.24*2=0.48)

6Count5average
114.433+-0.156mm

43

Deviation = 1.4 mm

210114114.5115height [mm]115.5116

DesignValue

Dumbbell Before tuningTried to extend each dumbbells by ~1 mm.
Fix two plates by bolts.

Extension

Dumbbell-height measurement and tuning
Regular dumbbell
after tuning

design value=115.864(included EBW shrinkage
eqator*2=0.24*2=0.48)

1 mm

8

N=12average
115.783+-0.133mm

76Count5

Deviation = 0.08 mm

432

10Dumbbell After tuning
114114.5115height [mm]115.5116

DesignValueBeam Pipe
80 phi Nb Beam-pipe (input-coupler)

108 phi Nb Beam-pipe (pickup)

End-group80 phi Beam Pipe
(Nb model)

Nb tubefor HOM coupler

108 phi Beam Pipe
(Cu model)

HOM coupler(Cu model)

End-groupエンドプレートSUS Base-plate

HIP bonding
80 phiOuter Cap108 phi

Inner Cap

End-group EBW
Beam

108-phiBase-plate 108-phi beam-pipe+ Inner End-Cap

Beam

80-phiBase-plate 80-phi beam-pipe+ Outer End-Cap

End-group EBWBeam

EBW of SUS Base-plate

Beam

EBW of 108-phi beam-pipe

End-groupCavity welding: the general way
There are differences of welding processes in industry

11 pieces

27 pieces

31 pieceBeamGood inner surface(EBW with beam oscillation)

Bad EBW example

EBW of equator for 6 R-dumbbells
Beam

6 R-dumbbells

End-group EBWBeam

EBW of 80-phi beam-pipe + dumbbells

EBW completed

Fabrication of ICHIRO Cavity at KEK
EBW of dumbbells
Beam

EBW of end-beam-pipe

End-beam-pipes with
HOM and flanges

Beam

Beam

Four 9-cell ICHIRO high-gradient
LL Cavities were successfully
delivered to KEK ! (4 July 2005)

EBW of end-beam-pipes
and cell-part8

1st, 2nd, 3rd, 4th 9-cell ICHIRO cavities
without
HOM coupler

with
HOM coupler

with
HOM coupler

with
HOM coupler電子ビーム溶接の縮みの測定

EBW shrinkage
iris

0.148+-0.044 mm

equator

0.424+-0.125 mm

Dimensional measurements
Length of the cavities were measured by 3D-measurement machine.

Dimensional deviation of length (only 9-cell part: 1038.5 mm)-10 mm (1st 9-cell ICHIRO cavity)- 0.7 mm (2nd 9-cell ICHIRO cavity)
ダンベルのチューニング
- 0.1 mm (3rd 9-cell ICHIRO cavity)- 0.1 mm (4th 9-cell ICHIRO cavity)
ダンベルのチューニング
作業者の学習効果

形状測定
Side C

空洞の直線度の3次元形状測定器による測定。

Cell
Ｎｏ，9CellＮｏ，1Side B

Cross-section viewYX-0.5

0.5-0.5mm

Deviation fr om str aight lin e
[mm]

0.5

0.3
0.2
0.1
0-0.1
-0.2
-0.3
0123 4 5 6 7
Cell Number

89 10電場の平坦度のチューニング
Set-up for field profile measurements: a metallic needle is perturbing the rf
fields while it is pulled through the cavity along its axis; the stored energy ineach cell is recorded.

ビードプル法金属の数珠球プレチューニング前後の電場平坦度
π mode frequency 1298.774 MHz

π mode frequency 1298.547 MHz
ICHIRO 1st Cavity

ICHIRO 1st0-60-20-70
phase[degree]-80-40phase[degree]-90-60-100-80-110

-100
0

100

200

300
time[s]400

Field flatness = 0.1 %(as delivered to KEK)

500

0

100

200

300

400

500

time[s]Field flatness = 98 %(after pre-tuning)600プレチューニング
ステッピングモーター

ビード線

アンテナ付フランジ

アイリス部に挿入される爪アイリス部に挿入される爪プレチューニング
金属の数珠球アンテナ

爪で締め付けている様子