ML18139A619
| ML18139A619 | |
| Person / Time | |
|---|---|
| Site: | Surry  |
| Issue date: | 08/04/1980 |
| From: | Spencer W VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.) |
| To: | James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| References | |
| 943C-110879, IEB-79-02, IEB-79-14, IEB-79-2, NUDOCS 8008060251 | |
| Download: ML18139A619 (5) | |
Text
f.,,*
Mr. James P. 0 1 Reilly, 01 rector Office of Inspection & Enforcement
- u. S. Nuclear Regulatory Cmm11ssion Region I I 101 r-larietta Street. Suite 3100 Atlanta) Gecrgia 30303 Dear t*ir *. O' Rei l1y; August 4, 19_80
,e Serial No. 943C/110879 PSE&C/ RHW, I I I : bmt Docket No. 50-281 License WO. DPR-37 FINAL REPORT ON I. L BULLETIN NO. 79... 02 *
- f1EVISiillf1fo. 2.
SURRY POl~ER STATION UNIT 2 To assure operability of Seismic Category r' piping systems in a seismic ~vent, the program for meeting the requirements of I.E. i3u1letin 79-02, 11Pipe Support Base Piate Designs* Using Concrete Expansion Ancllorsll was integrated \\'!ith _the piping req analysis efforts associated ~*fith the NRC Order* to Sirnw Cause dated March 13, 1979, anct I.E. Bulletin No. 79-14. *i'\\11 pipe _support huse plates within this scope have been analyzed considering !Jase plate flexibility.
All anchor bolt design loads meet the factors of* safaty required by the Bulletin.
Base plates for M\\rJ pipe supports required by the piping reanalysis and all-existfo!} pipe supports which are within the seismic boundary of the systems were analyzed for bnse plate flexibility.
Existing n~se plates and*anchor bolts which did not meet the design requirements were modified to meet the Bulletin,requirements.
1:-ii lti bolts were installed with new base plates and existino anchor *bolt,repairs and mod1ficat1ons.* These anchor bolts were installed in accordance with the ma*nufacturer*s requirements trnsed upon on-site testing. conducted at Surry Power Station by Hil ti, Inc.
To ensure. the adequacy of existing anchor bolts' an anchor bolt inspection and-*
testing program wo.s conductea. T,1is program involved inspecting and tension testing one anchor bolt per accessiole buse plate. Where the first anchor bolt was found to be inadequate, the base plate was reanalyzed with the discrepant bolt missing and the rsma.ining bolts inspected und tested to the new higher a.nchor bolt load *to ensure adequacy of the anchorage system.* All inadequate anchor bolts identified*were replaced.
Test resuHs. shO\\*/ that 97 percent of the base plates were adequate to,provide the required support anchorage.
Since all pipe support base plates have been reanalyzed and verified to meet the design requirements and since the 1nspect1on and test results show that the anchor bolts are adequately installed to perform their intended function> we feel that the requirements of LL Bulletin 79-o;:: have been sa~isfied for Surry Unit 2.
- Items one through six of the Bulletin are addressed below.
- 1.
All pipe support base plates have been analyzed considering base plate flexibility and modifications made where the base plate or anchor-bolts
e were found inadequate by analysis. Finite element analysis was performed using the ANSYS computer program as provided by the Owner's Group organized by Teledjme Engineering Services *. A de?criptio*n of this program was sub-mitted to the NRG as Technical Report TR-3501-1, Revision.I 11 Sunm1ary Report, Generic Response to USNRC I&E Bulletin No. 79-02, Base Plate/Concrete Expan-sion Anchor Bolts" by Teledyne Engineering Services.
In som!2 cases where the support plate could not be modeled in the computer program, hand calcula-tions ~*1ere performed allowing sufficient margin for base plate flexibility and prying. action.
- 2.
The factors of safety required by the Bulletin, four for wedge type anchors and five for she 11 type anchors, w12re used to determine. the anchor bolt allowable loads for the -reanalysis.
..C\\ll base plates \\*Jere reanalyzed to ensure that these factors of safety 1-vere met:
~~here the factors of safety*
were not met by analysis, rndifica.tions were ~,rovided to ensure t11e appro-priate factor of stfety.
- Ti1e original desig*n *for anchor bolts at Surry vrns based on a factor cf safety of four.for all 2..r;chor bolts based on a design concrete strength of 3000 psi.
Iri conjunction with IE Bulletin 79-02, a concrete inspection program was performed to* demonstrate a concret~
strength of 4000 psi vJhich vmuld provide the factor of safety of fiVl~
required by the Dulleti_n.
Thirty-two Uindsor.Probe Tests ','Jere performed at various locations tiwoughout the p*lant (Surry Unit$ 1 & 2) to provide data for the evaluAtion.
The results of this orogfcim show a 95 percent corrfiJence level of at least 4000* psi concrete.
Therefore, the *reananalysis was. based on 4-00(J psi concrete with the. factors of safety *of four and five..
required by the Bu 11_etfo.
- 3.
- No special des*ign require:;nents: for the a11chor _b.olts to vlithstand cyclic loads.v1ere appl_ied.
Testing" performed* for the Gvmer 1s Group, the results of.which are presented in.Tethnical R2poft TR~3501-1 referenced earlier,
- indicates that cyclic,loading on the anchors does not res*u1t in a* general.
reduction.of the uldmate capacity of the anchor.
Bolts for *shell type anchrirs (Phillips Red Head Self-Drilling An~hors) were tightened snugly, but
- wer~ not pieloacied.
Wedge anchors (Hilti bolts) were preloaded to-the design allowable load.
- 4.
To ensllr.e that the design requ"irernents h'ave been*r,1et for the.installed anchor bolts, an inspection and testing ~rograiwas conducted.
Under this progra~
one anchor bolt per accessibl.e base plate was inspected ~ncl t~nsip~ tested*
to at least the anchor bolt design load.
Anchor bolt installijtiohs which
\\rJere suspect based on the v**isL1al insp*e*ction, were *tension tested to at least the anchor bolt design allowabl¢-.lpad (20 perc~n~ of the manufacturer's ultimate) and evaluated for *a --factor of safety of fivef -by'_tensfon testing
- to five times the design load or deter1i1ining the anchor capacity.based on the results of the visual insp~ction *. When the anchor was found to be inadequate as a.result of.the ev*a1uation.or slippage. of gieater than 1/16 11 under the tension test, the base plate was reanalyzed with that bolt missing.
The remaining bolts on the base plate were inspected and tested for adequacy under the* higher redistributed load when.the reanalysis was acceptable. or for the original design load when the loads.could not be redistributed.
Inspection and test results showed that 97 percent of the base plates were acceptable.
All anchor bolts which were inadequate or damaged were replaced to ensure adequacy of the anchora9e system.
-3~
e In order to evaluate operability of each Seismic Category I piping sys-tem the anchor bolt inspection and test results were recorded on a sys-tem basis. The system designations as shown in Volume 5, Table 15.2.1-1 of. the Surry Final Safety Analysis Report were used in conjunction with the QA Category I piping Line Table to determine systems for I.E.Bulletin 79-02 purposes.
Of the 14 systems for which anchor bolt inspections were performed, 12 of the systems had acceptance percentages greater than 95
. percent. The acceptance percentages* for the other two syste11.s, Reactor Coolant and Residual Heat Removal, were 94.7 percent and 92.1 percent, respectively.
For all systems the base plates inaccessible for bolt in-spection and testing had remote visual inspections performed to ensure that all anchor bolts were present and no gross deficiencies existed.
For the two systems with less than 95 percent ~cceptance the inaccessible base plates were further evaluated to:ensure high design factors of safety greater than those required by the Bulletin.
Review of the base plates wllere* anchor bolts* were *found to be-inadequate did not indicate any common characteristic (i.e., floor plates, wall plates,*or ceiling plates) which would necessitate further inspection and testing of the inaccessible base plates with a particular characteristic. Final inspection and test results are presented in Attachment I.
Piping syste1,1s 2 incl1es in diameter or less v,ere originally designed by a chart analysis method.
To ensure adequacy of the base plates and anchor bolts in justifying operability of the small bore piping, a sampling pro-gram was initiated. Five 2-inch lines were selected as ~epresentative of the small bore piping. Three safety injection lines and two chemical volume and control lines which have a total of 22 supports with 43 base plates vJere analyzed in this effort.. Base plate analysis efforts show anchor bolt factors of safety ranging from 5.2 to 638 vlith the majority of anchor bolts having design factors of safety above 60.
Seventy-three anchor bolts on 12 of the base plates \\"ere inspected and ten-sion tested. Sixty-eight of these ancl1or _bolts, 93 pe~cent, were accepte.d.
The base plates for the five rejected anchors were reanalyzed with the dis-crepant bolts missing and all were fo~nd acceptable and within the allowable limits. All anchor bolts which were inadequate or damaged were replaced *to ensure adequacy of the anchorage system.
The small bore piping base plates.and anchor bolts were. designed and* installed by the same /VE and contractor that performed the* work on the large bore *
- piping. Therefore, based on the above results t'l'hicl1 are consistent with the large bore anchor bolt program, it is believed that a sufficient degree of conservatism exists in the base plates and anchor bolts of the small bore piping to justify acceptance of this piping.
- 5.
All Seismic Category I pipe supports on masonry walls were resupported with-out attachment to the. masonry walls. Details of our inspections were pro-vided in our letters of December 7, 1979, Serial No. 943A/110879 and January 30, 1980, Serial No. 943B/110879.
e
-.e
( 1'\\ 6.
Seismic Category I pipe supports using structural steel 'Shapes anchored with concrete expansion anchor ~alts were analyzed and inspected to the same.criteria*as pipe supports i,,jith base plate.s~
Th-is. le~ter represents ou*r final report. on* I.E. _Bulletin 79-02 for Surry Unit 2.*
Shaul,d you *have :any question or require further information, pl ease cont~.ct us.
Very tru 1y. yours,
.. *,*j&//
.,iV>~
...... I
. */J *. C.::;pencer Vice Pfeii~~ht -.P60er Stati6n
- -- tnt::i neeri n6 inc!**.cons true ti on. Services
'<J Nr. HJ1<61ci j:**penton, Oirector* *... *
- Of~ice of~Nutl~ar Reactbr ~e 0 ~liti6n
'. ~.
\\
. _'::},
2 3
4 5
6 7
8 BA 8B 9
10 i
(./)
=
(/)
C.!)
<<:t" l.Ll u
w
~
z I
I-
. C!:l f-(Y)
<C z
- r:
<::(
f-I
_J
__J 3
__J
(/)
N CL 0::::
<::(
0...
LJ 1--i -
t-1 z:
z r.n
~
~
w
- > 0 0
I-c::r:
I w
w z
(/)
CYt-1 1---i
_J a:,.
(/)
0
<C LLJ I-I-
00 c<5
<::(
~
C.!)
t-1 co O::::<C 1---i.
coz:
r--
co z
f- -
=>
Cl 1-f ---
(/)
1--i
<::(
(./)
(/) _J Cl LLl I-
<..D
- c w
g
(/)
I-1-<C c:i::
_J (/)
(/) -
f-I-
- J
_J
_J>
z:
co LL.I Lt:.1*
- 0) 1--i z
<::(
0...
0 ow o::::o
<Cl-I-
3:
0
__J
- 3 Cl 0
=
co w 1--i I-c::r:
1--i 0...
w 0..
0 f. CL 0::
_J V) z f-0 oz:
LJ... <::(
L1'J Lu CL w
0
<::(
w LJ...
w w
LLJ <C
<::( :::J UI-I-
1--i
__J
(/)
~
1--i I-I'-
I-
_J ULL w
c::r:
f-
- J
<::(
0 c:::(
. CL u
(".!:)
oc::r:
c::r: <C
_J,
_J
,:::(
0..
co 0
_J w
wz w>
z co CL
__J 0
~
0...
u r-:i,__.
f-W
- >CJ c::r:
- J 0...
w
. (/)
(/)
u LLJ I-0...
w I-LL!
0...
__J
- /'l f-(/)f-w c::r:
0:::: (./)
we
- c,___,.
CL.
_J 0
w a:i
.LJ -'
w __J
(/)
w uz:
I-LL w
co 0...
f-1--i
-o f-0 c:i::
>- I-uc::r:
u
<C rc::c:
(/)
- i:: co
,:::( co co
_J
_J
,:::(
30 u
I-I-
__J
(/)
_J
_J
--l
_J 0::::
a C) c::r:
0..
0::::
0...
w
- ,_ 0::::
0... 0::::
Cl c::r:
<CW VJZ tn ::E:
LL!
0 u
0 0
w t-1
,_, :c w 1--i w
_J
(_)
SYSTEM 0...
lJ.J u
.LJ :c w:c f-I-
1 1 1-.u.1.
c::r:
(_)
0..
~
c:I;
~~
UlU
(/)
...... e::::
,:::( (/)
c::r: 0::::
I-c::r:
z
<::( z w
z z::::>
.....!W
_J LJ.J C).
(/)
1--i
- i:i,:::(
co,:::(
I-
,_. LL o..r 0:. 3 I-
~
COMPONENT COOLING (INCLUD-ING NEUTRON SHIELD TANK COOLING) 18 23 4
8 0
11 11 0
0 0
1: l 100 CHEMICAL VOLUME AND CONTROL 137 201 30 74 6
97 94 3
2 r
96 99 r CONTAINMENT SPRAY 17 21 0
8 1
13 12*
1 1
0 13:
100 i SAFETY INJECTION 149 241 45 58 15 138 122 16 10 6
13,2'.
95.:
REACTOR COOLANT 47 78 23 17 2
38 30 8
6 2
36 94.:
RESIDUAL HEAT REMOVAL 45 70 22 10 8
38 33 5**
2 3
35' 92.:
CONDENSATE AND FEEDWATER (INCLUDING AUXILIARY FEED-WATER 61 98 14 31 6
53 53 0
0 0
- 53.
- 100 SECONDARY VENT ANO DRAIN (S.G. BL0~10mm) 15 lfr o-1 0
15 14 1
1 0
15 100 SERVI CE \\.J.l\\TER
- 14.
16 0
3
- 0.
13 13 0
0
' 0 13; 100 MAIN STEAM (INCLUDING HIGH PRESSURE STEAM DRAINS) 7 15 1
12 I
2 2
0 0
0 2
100 RECIRCULATION SPRAY 30 39 2
4 5
33 31 2
I I
32
- 97.
PRIMARY VENT AND DRAIN 8
10 5
3 2
2 2
0 0
0 2'
100 REACTOR CAVITY PURIFICATION 6
12 -
3 6
0 3
3 0
0 0
3 100 CONTAINMENT VACUUM 1
1 0
-o 0
I 1
Q o*
.0 1
100 TOTAL 556 843 149 236 46 457 421 36 23 13 444 97.: