JAERI-Conf 95-021

PA28
ALIGNMENT OF MAGNETS FOR THE SPring- 8 SYNCHROTRON
Kenji FUKAMI, Hiroto YONEHARA, Hiromitsu SUZUKI, Tsuyoshi AOKI,Shigeki OHZUCHI, Souichiro HAYASHI,Yutaka HIRATA*, Teruyasu NAGAFUCHI*, Norio SUETAKE*,
Yukio YOSHIWARA*, Hiromasa ffOH*
JAERI- RIKEN SPring- 8 Project Team, Kamigori, Hyogo 678-12, Japan*Toshiba Corporation, 1-6, Uchisaiwai-cho 1-chome, Chiyoda-ku, Tokyo 100, JapanThe second level is the network for the precisealignment of the magnets.

Abstract
SPring- 8 Synchrotron ring is composed of 64dipoles, 80 quadrupoles and 60 sextupoles. The 80
quadrupoles and the 60 sextupoles are ·supported ongirders. The circumference of the ring is about 400m.
Since the tunnel of this ring is very narrow,
SMART310, laser tracker for 3D measurements ofmoving targets, is used for the alignment. This paper
will present the alignment method, results and present
status.

2. Tolerances
The specification of the tolerance of the alignmentis relative precision of ± 0.2mm in radial direction,
vertical direction and beam direction. And ± 0.2mrad intilt for the magnets. Table 1 shows the deviation of therelative precision of the alignment of each magnets.
Table 1
Deviation of the relative precision.

1. Introduction
SPring- 8 Synchrotron ring is under construction
now. In June 1995, we began with the first survey ofreference points for prealignment. We will finish thealignment of the magnets . until January 1996. The
alignment method is based on reference points inside
the ring since there is no reference points outside thering. This alignment consists of two levels. The firstlevel is the network which survey and set the reference
points of the prealignment for installing the magnets.

Vertical Beam

Tilt

MagnetRadialDipole±0.2mm ±0.2mm ±0.2mm ±0.2mrad

Quadrupole±0.2mm ±0.2mm ±0.2mm ±0.2mrad

Sextupole±0.2mm ±0.2mm ±0.2mm ±0.2mrad

Correction± l.Omm ± l.Omm ± l.Omm ± l.Omrad

BMC16S3

Fig.1 Reference points of SPring- 8 Synchrotron- 103-

JAERI-Conf 95-021

3. Alignment Method
3.1 Reference Points Setting
The first level of the alignment is setting thereference points for the magnets installation to thetunnel and prealignment. We survey the reference
points and set them for the proper location.
Fig. 1 shows the reference points of thesynchrotron ring. L1 and L2 which are on the injection
line from Linac ensure the correct location andorientation of the ring. Based upon them, we set thereference points Sl to S12. These reference points areimbedded in the floor and are able to adjust the X- Yaxis of the location. Monuments are set up on thepoints.
Using 11, L2 and other supplementary points,
reference points of the straight line are set.
Since the Tunnel is very narrow and reference
points are very few, it is remarkably difficult to realize
highly accurate positioning of the reference points bytriangle network calculation. For this reason, we use thecenter location of the 64 dipole magnets as
supplementary points. Survey network comprises nearly
80 points of reference points and supplementary points.
The objective of the first level alignment is that thedeviation of the network calculation of the reference
points is less than ± 1mm.
The height reference is taken from the Linac
injection line. Beam line is 1200mm height from thefloor. This height reference is transferred to 1560mm
height which is visible after the installing of themagnets. Nearly 10 height reference points like this are
set up on the wall along the tunnel.
SMART310, theodolite, N3 and NA2 are used assurvey equipment. Direction and Angle are measured bytheodolite. Distance is measured with SMART310.
Height is measured by N3.

the network calculation. There are three fiducials on adipole magnet. "BMU'' means up stream, ''BMC" means
center and "BMD" means down stream. Sphere mounted
retroreflector of SMART310 is positioned on the threefiducials.
According to the measurement data, magnets arecorrectly positioned.
Fig. 2 shows the precise alignment method of themagnets. Using the reference positions as reference,
position of the three fiducials are measured. Using theprevious data as reference, three fiducials of the next
magnet are measured, and so on. Mter the survey iscompleted, each position is calculated by triangle
network. If the result is not satisfactory, correct theposition of the magnets and submit the network
calculation again. This precise alignment is made in two
rounds of the tunnel.
4. Instrumentation
Due to the narrowness of the tunnel, SMART310is used for this alignment(see Fig.3). SMART310 islaser tracking system for 3D measurements. This is asingle instrument for measuring angles and distanceswith automatic tracking of freely moving retrorefiector.
The following is the instrumentation for thisalignment.
(1) Distance
SMART 310 (Leica)
Accuracy
distance resolution± 1.26 t.t m
Inside Micrometer
1500mm Accuracy max.± 0.04mm
5000mm Accuracy max.±0.115mm(2) Direction and angle
SMART310(Leica)
Accuracy
angle resolution
0.7''

3.2 Prealignment
At the reference points setting, supplementary
points of 64 dipoles are simultaneously set, marked andinked on the floor. Magnets are installed in the tunnel
according to this markings and inking.
The objective of this prealignment is as follows.
(!)Radial± 1mm(2)Beam axis
± lmm(3)Vertical±0.5mm(4)Tilt
0.2mm!m
3.3 Precise Alignment
Monuments are set on the reference points.
SMART310, Theodolite, N3 and NA2 are used assurvey equipment..
Reference points are measured with SMART310
for confirmation.
Fiducials on the 64 dipole magnets are used as
supplementary points in order to obtain the accuracy of- 104-Fig. 2 Precise alignment method

JAERI-Conf 95-021

Theodolite T2000, T2000S(Wild)
Standard deviation
Hz: 0.5" ; V: 0.5"

(3) Height
N3, NA2(Leica)
Standard deviation for lkm(4) Inclination
DL- D3(Nigata seiki)
Accuracy 0.01mrn/m(5) Plumbing
ZNL(Wild) 1:30000± 0.2mm

5. Results
In June 1995, we have finished reference points
setting.
The deviations which is the difference between
designed positions and calculated positions by network
calculation were in the range of nearly ± 1mm.
6. Conclusion
The alignment of SPring- 8 Synchrotron is inprogress now. 64 BMC's were set on the floor asmarking. Applying these markings, positions of allcomponents were inked on the floor.
In August and September 1995, according to theBMC markings and inking, magnets will be carried in
the tunnel, and supports and girders will be fixed on thefloor. Prealignment will be carried out after that.
Precise alignment will begin in November 1995. It
requires three months to complete the second level ofthe alignment.
Fig. 4 Reference point and supplementary point setting

Fig.3 SMART310 System-105-