-
Notifications
You must be signed in to change notification settings - Fork 10
/
ORNL-TM-0910.txt
5651 lines (2882 loc) · 116 KB
/
ORNL-TM-0910.txt
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
3
i
i OAK RIDGE NATIONAI. I.ABO RATO
o ~operated by
UNION CARBIDE CORPORATION
- """‘f,_NUCLEAR DIVISION
U S ATOMIC ENERGY COMMISSION
77777 ORNL TM 910
Lty .
MSRE DESIGN AN-'D OPERATIONS REPORT
S PART X
L
-
r S S (i iy AT 3 L e e SR TR
-::"fi Nk B . . . : ‘ ; L
| L gt TR T : AT Sy L .
MAINTENANCE V_EQUVIPMENT AND PROCEDURES
R BIumberg ) E C. I"IISe - 7. o o !
. “IITICE TI‘us documentii:ontmns “informetion of a prehmmary nature . S
" “and was prepared primarily’ for- internal use at the Ook Ridge National - -
- Laboratory. It is subject: to ravtsmn or correchon und iherefore does e T
not represent o Imol feport ' et T
- ISTRIBUTION OF THIS OUTUNE 1S ORDHTTES
i
{
F
t
;
¥
{
P i .
LEGAL NOTICE
This report was prepored ¢s on account of Govornmnt sponsored work. Neither the Unlf.d Siahl,w
not the Commission, nor any person acting on beholf of the Commission:
A. Maokes any woarranty or representation, sxpressed or implied, with respect to the accmacy,
completeness, or usefulness of the information contoined in this report, or that the use of
any information, apparatus, method, or _process disclosed in this report may not infringe
privately owned rights; or -
B. Assumes any lisbilities with respect to fl'ne use of, or for damages nsulting from the use of
any information, apparatus, method, or process disclosed in this report,
As used in the obove, “‘person acting on behalf of the Commission® includes any omployee or .
- contractor of the Commission, or smployee of such contractor, to the extent that such employee
or contractor of the Commission, or smployse of such contractor prepares, disseminates, or
_ provides access to, any information pursuant to his employmenf or contract with the Commission,
or his employment with such contractor.. .
e
O &
e
r
iflv‘
Contract No. W-7405-eng-26
Reactor Division
MSRE DESIGN AND OPERATIONS REPORT
PART X
MAINTENANCE EQUIPMENT AND PROCEDURES
R. Blumberg E. C. Hise
JUNE 1968
OAK RIDGE NATIONAIL LABORATORY
| Oak Ridge, Tennessee
.- - operated by - :
UNION CARBIDE CORPORATION
for the
. U.S.. ATOMIC ENERGY COMMISSION
ORNL-TM-910
i o
D
x’?._‘,t.,._,_. : V
ERZ
b
iii
PREFACE
A record of the methods of maintaining the radioactive portlons
of the Molten Salt Reactor Experiment (MSRE) is presented in this
report. In Section 2, overall descriptions are given of the components
and the methods of maintenance. Section 3 presents the procedures
written from the standpoint of the people who perform the work. The
Appendix lists reference material that will be useful when detailed
information is required.
The report was originally prepared before the MSRE began power
operation and thus before there was any experience in radiocactive ‘
maintenance of it. Since that time, the MSRE has been operated and
maintained successfully, and we have had the opportunlty to observe
how our maintenance plans have worked. In general, our basic methods
and original planning have served quite well.
There is one aspect of our experience, however, that bears on
the materisl contained herein. We have found that changes in tools,
methods, reactor equipment, and administration of the maintenance
operation make it necessary to prepare new and fully detailed
procedures for most shutdown‘work. These procedures are then used
to implement the functlonlng of a complex operation involving many
people. Therefore the procedures in this report reflect present
methods but not the full detail that is actually required.
<w
o
«) d‘m
‘
1ot
- ACKNOWLEDGEMENT
We wish to acknowledge the contributions of other members of
the Reactor Division to this report. P. P. Holz did the original
design and description of the portable maintenance shield. B. H.
Webster did the same for the graphite-sampling technique. J. R.
- Shugart not only wrote and rewrote many procedures, but also made
them work at the MSRE. R. B. Briggs and Dunlap Scott reviewed
the original manuscript and provided many helpful suggestlons for
- the preparatlon of the finished report.
_M‘ fa:
Pl )
1ok
o
e
Lt
A Y
i
s
C
vii
INDEX TO REPORT SERTES.
. This report is one of a series that describes the design and
operation of the Molten-Salt Reactor Experiment. . All the“reports are
llsted below.‘
ORNL-TM-TEB
.ORNL-']M-'-729 |
0RNL-EM%73O
ORNL-TM-732
" ORNL-TM-T33
ORNL-TM-907
ORNL-TM-908
ORNL-TM-909 -
- Safety Procedures and Emergency Plans, by
ORNL-TM-910
MSRE Des1gn and Operations Report Part I,
Description of Reactor Design by
R. C. Robertson oy
MSRE Design and Opersations Report,“Part 1T,
Nuclear and Process Instrumentation, by
“de Ro Tallackson
MSRE Design and Operations Report, Part III,
Nuclear Analysis, by P. N. Haubenreich and
J. R. Engel, B. E. Prince, and H. C. Claiborne
MSRE Design and Operations Report, Part V,
- Reactor Safety Analysis Report, by S. E. Beall,
P. N, Haubenreich, R. B. Lindasuer, and
J. R. Tallackson ' ' ,
QMSRE Des1gn and Operations Report, Part VI,
Operatlng Limits, by S. E Beall and
R. H. Guymon - _
MSRE-Design”and Operations Report, Part VII,'
Fuel Handling and Processing Plant, by
R. B. Lindauer
MSRE Design and Operations Reporb, Part VIIIT,
Operating Procedures, by R. H. Guymon
MSRE'Deslgn and Operations Report, Part IX,
R H. Guymon
MSRE Design and Operatlons Report Part X,
Maintenance Equipment and Procedures, by
E. C Hlse and R. Blumberg K
ix
‘-J CONTENTS
K- ABSTRACT sueevseovocssoaasesscassassosoasosaasssessssssossossscsas
l. INTRODUCTION ssvevcesassseversosvssosossoasassssncssassossnaanssss
) 2. DESCRIPTION OF THE MAINTENANCE SYSTEM +eeveavecsecrnosassaoss
2.1 Maintenance Equipment and General Methods «.....c..ev..
2.2 Maintenance Control Room and Facilities for |
Remote Operatlon ciBEs s eEreav T sas et e s e b e N e e
2.3 Portable Maintenance SHield ...eeeeeeeesocssoseensenes
2.4 Jigs and Fixtures for Assembling MSRE Components s.sese
2.5 . Freeze-Flange Maintenance I P T T T
2.6 Fuel—Pump MaintenanCe ..e.ceveeveccesscscsaesoossasanns
2.7 Graphite Sampler and Control Rods .....ececcvvecnacosns
2.8 ‘Braze Joint ......................,..-.........,.......f
2.9 Maintenance of the Sampler-Enricher .e.esceeesesessssss
. 2.10 Miscellaneous Long-Handled Tools Ceeirenesesaanesanenes
” 3. DETATLED MAINTENANCE FROCEDURES «revsvessensonesseneonennsns
’%‘ 3.1 The Radla.tlon and Contamlnatlon Problem .ceeecscsccsece
3.2 Maintenance Control Room and Remote Fa01llt1es cveceses
‘3.3 Procedure for Use with the Portable Maintenance
Shield .u.ivevecsonsicsssesssesacsacosssssosssnsssosscas
3.4 Procedures for U31ng Freeze-Flange Manlpulatlng
TOOLS teveeeroroescorasnncersarecnsnsanosssssasancans .o
3.5 'Fuel-Pump Maintenance ............;..............;,....
3.6 Procedures for Handling Survelllance Samples and -
o Control Rods «ceevevrevscrccsencosancscncensccecssacnans
3.7 :Procedure for Bra21ng & Joint .....................}...
3.8 Procedures for Malntenance of the Sampler—Enrlcher,....
Appendix A. LIST OF REMOTE MAINTENANCE REFERENCE INFORMATION .
Appefidix'B.'fMBRE PORTABLE MAINTENANCE SHIELD cesecesasssscnsesues
A Appendix C. GRAPHITE SAMPLER AND CONTROL ROD MA]]\TTENANCE
3 e FACILITY seveccossnccrscsnaanascsssascccanossosossoe
g ‘Appendix D. LONG-HANDLED TOOLS AND MISCELLANEOUS EQUIPMENT ..... -
| - Appendix E. IN-CELL EQUIPMENT tessececassesseescssssunsannssasana
‘Efl . Appendix F. JIGS AND FIXTURES teceeveosvosassscscscscnsscatsscsccasn
Page
xi
1
4
4
15
15
23
23
28
37
37
41
41
42
43
45
51
53
62
67
71
72
T4
77
78
N,
"‘ t, [‘ [
)
M
¥
xi
- ABSTRACT -
A record of the methods of maintéining the radio-
active portions of the Molten Salt Reactor Experiment
(MSRE) is presented. The maintenance system utilizes
long-handled tools operated through & movable shield
for most of the in-cell manipulations. For some
radioactive transfer and setup tasks that cannot be
handled otherwise, a crané that is operated remotely
from a shielded control room is used. Overall
descriptions are given of the components and the
methods of maintenance, the procedures written from
the standpoint of the people who perform the work are
presented. Reference material that will be useful
when detailed information is required is included.
’
5 (o
o
4 l‘fl"-
eh
o
e
'-fl
- -1, INTRODUCTION
The MSRE is a 7.5-Mwt circulating-fuel reactor in which.?ssU
fuel dissolved in a solution of lithium and beryllium fluorides
is pumped around a closed loop at 1200° F. A drawing of the reactor
arrangement is shown in Fig. 1. The reactor plant was completely
-described in this series of reports by Robertson.1 Some of the
advantages of this reactor concept are related directly to the
liquid nature of the fuel and are due to the éase of moving the
bulk of the fuel inside piping systems, removing reactor poisons,
reprocessing to remove fission products, and adding new fissionable
material to make up for burnup. However, the same liquid property
causes radioactivity to be distributed throughout the primary
- systems. Therefore special means are required for maintaining all
the equipment that comes in contact with or is physically near the
" fuel salt and off-gas systems. The demonstration of capability in
this area became one of the primary objectives of the program.
The maintenance system includes many different kinds of
equipment located both in and out of the radioactive areas. Besides
physical equipment, & certain amount of informetion must also be
considered as part of our maintenance system. This information
‘exists as written procedures, drawings, photographs, and "know-how"
‘of trained experienced personnel
Early in the program.it was!recognized that the design of each
component had to include provisions for maintenance, and the steps
in the achievment of this goal included a design surveillance
. program. Thus those who had the maintenance responsibility had an
opportunity to influence the system and component design in the
early stages.. This activity toock varying degrees of participation
from consultation and approval to detailed designs and layouts.
Surveillance of the design was followed by a similar program during
‘the construction, assembly, and installation stages. Accompanying:
the field work of 1nsta111ng reactor components was & demonstration
and practice program in which selected components were handled with
remote-maintenance tools and methods. Many corrections were made
during this period to inmprove the basic designs and to correct
fabrlcatlon errors and maintenance techniques. In general, the
- process consisted of doing whatever was necessary to make the system
7 ,malntainable. The surveillance program and the demonstration
_ program were logical methods of assuring the malntalnabllity of the
system before power operation. These programs had the further
result of producing a nucleous of experlenced personnel at the
beginning of power operation at the MSRE, which has since been
expanded in the course. of several shutdowns to an adequate and
2R. C. Robertson, MSRE Design and Operations Report, Part I,
Description of Reactor De51gn, USAEC Report ORNL- TM—728 ORNL,
January 1965.
ORNL-DWG 63-1209R
REMOTE MAINTENANCE
CONTROL ROOM
s o
REACTOR CONTROL
ROOM
-
T
RN
4
J 9
{. REACTOR VESSEL ) 7. RADIATOR
2. HEAT EXCHANGER 8. COOLANT DRAIN TANK
3. FUEL PUMP 9. FANS
4, FREEZE FLANGE 10. FUEL DRAIN TANKS
5. THERMAL SHIELD 11. FLUSH TANK :
6. GOOLANT PUMP 12. CONTAINMENT VESSEL
13. FREEZE VALVE
Fig. 1. Sketch of MSRE Arrangement and Flow Diagram.
C
(w
R
")
i
nd
competent group. The recognition of the individual component nature
of the maintenance problem, the design and construction surveillance
effort, the demonstration program at the reactor, and the utilization
of developed personnel skills are parts of the approach used to assure
the maintainability of the MSRE.
2. DESCRIPTION OF THE MAINTENANCE SYSTEM
2.1 Maintenance EQuipment and General Methods
The system provided to maintain the MSRE is based on the
requirement that any failed component be replaceable with a new
interchangeable spare. Decontamination and subseguent repair of
failed components have been found to be possible and economically
attractive. However, decontamination and repair are not considered
to be the primary methods for maintenance. :Little effort. has.been
made to effect in-place repair. A major effort was made however
to achieve good component reliability. As the result of a combination
of many influences, the maintenance system was made flexible, simple,
rugged, and low cost. All the equipment that can be approached
directly is designed for conventicnal maintenance. This report is
concerned only with the equipment that cannct be approached directly
because of radioactivity. :
The four principal locations where remote maintenance is required
are the reactor cell, the drain tank cell, the venthouse, where there
is access to the off-gas system components, and the fuel-processing
cell. Fairly uniform methods are used for all these cells. The
ability to remove and replace every operating component in these N
areas has been accomplished through the use of appropriate disconnects
and mountings. The 5-in. circulating-system piping is joined by
mechanical disconnects consisting of the freeze flange developed
especially for molten-salt service. The 1-1/2-in,.fill-and-drain
system piping is of all-welded construction. Future joints will
be made by cutting and brazing with a technique developed especially
for this service. Piping conducting other fluids is connected by
ring-joint flanges or cone-seal disconnects. Electrical and instrument
wiring has plug-in disconnects constructed of materials suited to-
the environment. All the joinmts and disconnects are designed to be
readily operable from directly overhead. They are described in detail
later. The major components, such as the reactor vessel, the heat
exchanger, the pump, and the drain tank, as well as the smaller
components, such as the pipe and vessel heaters, valves, and motors,
are so disposed and mounted that after being disconnected they can
be removed by lifting straight upward.
The maintenance equipment design provides for the operation of
all the disconnects and the replacement of the smaller components
by the use of relatively simple long-handled tools operated directly
through the portable maintenance shield. The portable maintenance
shield can be placed over and will cover the opening left by the
- removal of two of the lower shield plugs, a space 4 ft. wide and up
' to 10 long. There are a variety of penetrations for inserting
lighting, viewing devices, and tools. An opening can also be
created through which small components will pass. A penetration
may be placed anywhere in the opening covered by the shield by a.
L ‘
x
<
o
.y
™
4
series of controlled movements. The design and use of the portable
maintenance shield are described in detail later. The -major components
are too large to pass through an opening 4 ft. wide and their removal
thus requires that a large portion of the cell top shielding be
removed and that remote-handling techniques be used. For this
‘operation, a shielded maintenance control room, remotely operated
cranes, and closed-circuit television were provided. The maintenance
control room (Fig. 2) overlooks the reactor cell, the drain tank cell,
and the building interior through shielding windows. It contains
controls for the 30-ton crane, the 10-ton crane, and the monitors for
the television system. Lift fixtures are provided that can be picked
up by crane and which, inturn, will pick up, transport. and release
the lower shield blocks and.beams and each of the magor components.
2.2 Maintenance Control Rodm and Facilities for Remote Operation
‘The maintenance control room and facilities for remote operation
consist of the remote maintenance control room; 30- and 10-ton cranes
operable from the control room; 1ift tongs for the lower shield blocks
for the reactor cell and drain-tank cell; lift fixtures for the
‘reactor vessel, heat exchanger, fuel pump, and drain tanks; and a
closed~circuit television system. The remote facilities are to be
used during any maintenance operation that requires the s;multaneous
removal of more than two lower shield blocks. Anticipated operations
in this category are replacement of the reactor vessel, the heat
exchanger, the pump bowl, and the drain and flush tanks.
_ The maintenance cofitrpl rdcmlhas'3-l/2-ft-thick concrete walls
to provide adequate shielding for any maintenance operation; three -
" windows to provide a view of the cells and building interior; crane,
-television, and lightlng controls, and radiation monitors, ventilation,
sanitary facllities and lights. Its floor is 10 ft. above the building
main floor and its interior dimensions are 14 by 19 ft. Personnel -
~access to the room is by an outside stairway on the west side of the
~ building. Equlpment access 1s by al x k- ft hatch 1n'the celllng. -
The ten-ton crane has flve speeds in. each of six directions
_controllable dlrectly from-a push-button pendant in the main building
or from a dial and toggle-switch console in the malntenance control
- room. - The signals from:the maintenance control room to the crane
travel via a trailing cable that must be connected by a cannon-type
plug located at the west end of the brldge when remote control is
~ desired; it is disconnected at all other times. This crane was ‘
rereeved for a hook travel from 875 ft 10-1/2 1n.to 823 ft 6 in. eleva%mon_
~ and is nov actually rated at 7-1/2 tons. L |
‘The 30-ton crane-has flverspeeds in each directioh‘contrbilafile
~ from the cab and three speeds in each direction controllable from
a dial and toggle-switch console in the maintenance control room.
It also has a power-driven rotating hook controllable from either
point, and a load cell with an indicator in the maintenance control
¥
WINDOW OVERLOOKING
DRAIN
b
~TANK CE{
1]
"
w
o
-5-through 8 show various-views-of this equipment..
room. The remote-control sighals are transmitted via trolley wire
-and need not be disconnected. The main circuit breaker for both
cranes is in a shieldéd area under the mafntenance control room and
is accessible during a remote-maintenance operation.
There are four-point (Fig:. 3) and two-poinmt lifting tongs for
the lower shield blocks, and a lifting tong for the lower shield
beams. The bails fit the hook of the 30-ton crane. The tongs lock
- alternately in the open and closed positions each time they are
picked up and set down. The sequence of operationsfor the tongs is
as follows: engage the crane hook in the bail and raise the tongs
(now locked in the open position); lower the tongs onto the plug
with the hooks in the lifting points until the tong weight is off
the crane; raise the tongs, which will automatically lock in the closed
position, and raise the shield plug; transport the load and lower it
~ until the tong welght is off the crane hook; raise the tongs, which
will now automatically lock in the open position, and release the
load. :
A lifting fixture is provided for each of the major camponents.
BEach fixture can be picked up and released by the crane and can in
turn pick up and release its component through use of the remotely
operated crane. These fixtures are on hand and have been used.
The television system consists of three cameras mounted on
pan and tilt mechanisms, two monitors, and a set of controls. For
a remote-maintenance operation the cameras are mounted in the
building on movable stands, as shown in Fig. 4, so as to command
two views of the operation which, along with the direct view through
the shielding window, provide complete coverage of the work area.
The use of orthogonal positioning of the cameras provides a feeling
of depth. The remote controls operate the pan, tilt, focus, zoom,
and iris. ' - '
2.3 Portasble Maintenance Shield
A portable maintenance shield was designed and fabricated to
‘provide shielding for maintenance operations with long-handled tools.
It shields the access area produced when any two adjacent lower roof
blocks are removed from the reactor or'the drain tank cells, It
'jaccommodates the long-handled tools, the lower shield blocks in both
reactor and drain tank cells, and some of the in-cell equlpment, and -
it is operated from the remote-malntenance control room. Figures
‘The portable malntenance shleld con51sts of four. ba81c components:
slide, modules, frame, and track. The slide is a slab of shielding
whose dimensions are 12 in. thick by 5 ft wide and either 8-1/2 or
13 ft long dépending on the usage. The slide includes a circular
cutout that accommodates & 35-in.-diam. geared plug. The plug,
in turn, has a series of cutouts for lights, windows, and tools.
ORNL-L-DWG &il93
Fig. 3. Remotely Operated Lifting Tongs for Shielding
Plugs.
e
v
=
5
10 | - ’
1
SR R
- EEEEY B [ e i ST = LN ROTATING
~ s
]
< ph
A
11
Y, e ORNL-DWG 67-13761