Transcript KEK Structure fabrication status

Flatness recovery technique
May 30, 2008
T. Higo and T. Takatomi
Flatness control
• We made T18_VG2.4_disk #1, #2 ( also #3 and #4) by outside company,
Morikawa.
• The machine, Seibu-denki, is precision lathe but the alignment of the axis
is intentionally slanted.
• A study was done to make the end surface to be adjusted by a NC
movement of making a cone shape with its minimum step of 0.1 micron.
• It seems we can control the surface well if we can accept the minimum
step of the NC control.
• How do you think this cure? If you accept it, we do not need to make the
final machining at KEK. If not, we do the final cut at KEK but it gives us
much work load.
• The cutting for the damping waveguide may simply makes us do the final
cut at KEK. It will be determined at the preparation stage of the fabrication.
I worry that some time is needed even for us because many years has
passed since we made a so-called butterfly cell for DDS3 etc.
• Please give us comments.
CLIC_vg1-A Flatness measurement
A-No.00 cupside
A-No.00 diskside
Distribution of Flatness
CLIC_vg1(A&B)
14
両面とも１μｍ程度中ベコになっている。
これは加工機の初期設定によるものと考えられる
ばらつきは±0.5 μｍ程度
12
Number
10
8
cup
disk
6
4
2
0
0.5
0.6
0.7
0.8
0.9
1
1.1
Flatness(μm)
1.2
1.3
1.4
1.5
１μｍ中高にすることで平面度±0.5 μｍが可能
Study condition in Japanese
•
試験、測定：株式会社森川製作所
•
試験内容：
加工プログラムにより中高に加工した場合の平面の評価
（0μｍ狙い、0.2 μｍ中高狙い、0.5 μｍ中高狙い）
•
加工条件：
– 加工機：西部電機旋盤ＳＮＣ－３５ＨＰ（最小設定単位：０．１μｍ）
– ワーク：無酸素銅（アニール無し）φ55×20
– 加工条件：
• 工具：単結晶ダイヤモンドバイト
• 加工液：トナオイルＳ(昭和シェル石油)
• チャック：三爪チャック（チャック圧0.07MPa)
• 回転数：500min-1
• 切削速度：0.015mm/rev
• 切り込み量:0.005mm
平面 ０μｍ狙い
平面 ０.2μｍ中高狙い
平面 ０.5μｍ中高狙い
0.5μｍ狙い平面写真
目視では段差は見られない
Result and discussion
• The shape due to three nails for chucking were found. We assume that
this is due to the rough machining, though we should confirm.
• Concave shape was confirmed without NC correction. The better flatness
this time is due to using a different machine, though of the same series.
– 0.5 micron: CLIC_VG1=SNC-20HP (Seibu-denki)
– 0.2 micron: Present test=SNC-35HP (Seibu-denki)
• The case of 0.5 micron target becomes 0.5 micron convex, as designed.
• The step of NC correction is 0.1 micron.
• I think the 0.1 micron step is tolerable.
• KEK or SLAC should check this conclusion experimentally. If no voids
remains after diffusion bonding, it should be OK.
• If OK, do we apply convex correction by say 0.2 microns?