Transcript BFW Fiducialization Procedure

Beam Finder Wire (BFW)
Fiducialization
Zack Wolf,
Dean Walters, James Bailey,
Eric Lundahl
October 20, 2005
BFW Fiducialization Procedure
Zack Wolf
1
[email protected]
Need For A BFW
The undulator will not steer the beam.
It will just radiate at the wrong wavelength.
The BFW allows this to be detected.
October 20, 2005
BFW Fiducialization Procedure
Zack Wolf
2
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BFW Specifications
LCLS PRD 1.4-004
October 20, 2005
BFW Fiducialization Procedure
Zack Wolf
3
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BFW Operation
Out:
The beam goes through a small
beampipe making a smooth transition
to external beampipes
In:
Wires are inserted into the beamline.
The whole girder is moved to scan the
wires across the beam.
October 20, 2005
BFW Fiducialization Procedure
Zack Wolf
4
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BFW Use
Either turn quad off,
or use wire system
to re-center on beam
October 20, 2005
BFW Fiducialization Procedure
Zack Wolf
5
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Fiducialization Accuracy Requirements
Rough Error budget:
1) Locate wire relative to local fiducials
(optically): 25 um
2) Locate local fiducials relative to
outside tooling balls (CMM): 15 um
3) Repeatability of positioning wires:
80 um in X, 30 um in Y
LCLS PRD 1.4-004
October 20, 2005
BFW Fiducialization Procedure
Zack Wolf
6
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Fiducializing
the
Beam Finder Wire
Dean Walters, James Bailey,
October 20, 2005
BFW Fiducialization Procedure
Zack Wolf
7
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Cases to Consider Fiducialization
Case 1 - Initial installation of the BFW
Below is the outline of the Initial Installation followed by
the outline of the Replacement of the BFW
Case 2 - Replacement of the BFW
The replacement of the BFW is the more difficult case
Since the case of replacement is constrained access-wise,
careful placement of fiducials and the BFW/Vacuum Chamber
is important.
October 20, 2005
BFW Fiducialization Procedure
Zack Wolf
8
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Case 1 - Initial Fiducializing of the BFW
Step 1 - Wire to BFW Frame Fiducials
BFW Frame
External Stationary Fiducials (ESF)
BFW Alignment Stand
External Moving Fiducials (EMF)
On the BFW Alignment Stand
the position of each wire can
be measured WRT the EMF
Measure the Beam Guide
WRT the EMF
With the BFW actuated in each
(up & down) position, adjust
the stops for each position
from the EMF to ESF per
nominal dimensions .
Beam Guide
Wire
October 20, 2005
BFW Fiducialization Procedure
Zack Wolf
9
[email protected]
Case 1 - Initial Fiducializing of the BFW
Step 2 - BFW Frame to vacuum Chamber Alignment
Bolt BFW Frame to
Vacuum Chamber and
make vacuum seal.
Adjust the lower stops
to place the Beam
Guide in the center of
the Chamber ports.
Then measure the
EMF WRT to CSF
Adjust the upper stops
to correctly place the
wires WRT the Girder
Axis (GA)
Then measure the
EMF WRT to CSF
Chamber Stationary Fiducials
(CSF)
BFW Chamber Alignment
Stand
October 20, 2005
BFW Fiducialization Procedure
Zack Wolf
10
[email protected]
Case 1 - Initial Fiducializing of the BFW
Step 3 - Alignment of BFW/Vacuum Chamber to Undulator Vacuum Chamber
The BFW Chamber
along with the BFW is
placed in the beam line.
Adjust the Chamber
supports to place the
upstream port in line
with the Undulator
Vacuum chamber.
The mating flanges
will have the ability to
self center to each
other.
Make up the vacuum
flange seal.
There will be the
ability to make fine
position adjustments
after the seal is
made.
Re-measure the
placement of the
Chamber CSF and the
EMF WRT to the GA
October 20, 2005
BFW Fiducialization Procedure
Zack Wolf
11
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Case 2 - Replacement of the BFW
Beam Finder Wire
1.
Assumptions for replacement of the
BFW.
a)
The existing BFW was aligned
b)
The BFW/Vacuum Pump chamber
stays in place in the beam line
c)
The BFW/Vacuum Pump
Chamber is supported so that
when the BFW is removed that it
remains accurately in place
October 20, 2005
BFW Fiducialization Procedure
BFW/Vacuum Pump
Chamber
Zack Wolf
12
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Case 2 - Replacement of the BFW
Step 1 – This is the same as Step 1 of the Initial
Fiducialization
Step 2 - In the case of replacement the data from Step 2 in
the initial case will be used with the new BFW frame.
Step 3 – This is different than the other Step 3 in that the
stops will be adjusted in the field using the preexisting data.
This will be more difficult since some lines-of-sight will be blocked
due to existing installed equipment.
Access to adjustments will also be more awkward in the field then in
Case 1 where the adjustments will be made in the lab.
The new installed assembly will be measured in both positions after
all adjustments have been made to record the final placement.
October 20, 2005
BFW Fiducialization Procedure
Zack Wolf
13
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How Fiducialization Is Really Done
Eric Lundahl
October 20, 2005
BFW Fiducialization Procedure
Zack Wolf
14
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Optically Find Wires WRT Local Fiducials
October 20, 2005
BFW Fiducialization Procedure
Zack Wolf
15
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Locate Tooling
Balls With CMM
October 20, 2005
BFW Fiducialization Procedure
Zack Wolf
16
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Previous SLAC Experience
October 20, 2005
BFW Fiducialization Procedure
Zack Wolf
17
[email protected]