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{{Adams | |||
| number = ML20154M087 | |||
| issue date = 05/18/1988 | |||
| title = Insp Rept 50-353/88-12 on 880425-0503.Violation Noted.Major Areas inspected:safety-related Electrical Sys,Components. Emergency Diesel Generator Maint,Electrical Const Insp of Wiring,Cables & Components | |||
| author name = Anderson C, Woodard C | |||
| author affiliation = NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) | |||
| addressee name = | |||
| addressee affiliation = | |||
| docket = 05000353 | |||
| license number = | |||
| contact person = | |||
| document report number = 50-353-88-12, NUDOCS 8806010169 | |||
| package number = ML20154M043 | |||
| document type = INSPECTION REPORT, NRC-GENERATED, INSPECTION REPORT, UTILITY, TEXT-INSPECTION & AUDIT & I&E CIRCULARS | |||
| page count = 13 | |||
}} | |||
See also: [[see also::IR 05000353/1988012]] | |||
=Text= | |||
{{#Wiki_filter:4 . | |||
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U.S. NUCLEAR REGULATORY COMMISSION | |||
-REGION I' | |||
Report No. 50-353/88-12 | |||
Docket No. 50-353 | |||
License No. CPPR-107 Priority - | |||
Category B | |||
;- Licensee: Philadelphia Electric Company | |||
2301 Market Street | |||
Philadelphia, PA -19101 | |||
Fa:ility Name: Limerick Nuclear Generating Station, Unit 2 | |||
Inspection At: Limerick, Pennsylvania | |||
8 | |||
Inspection Conducted: April 25 - May 3, 1988 | |||
-Inspector: O/0 L C. Cbbrd | |||
C. H. Woodard, Reactor Engineer | |||
r[n[if | |||
date | |||
Approved by: O | |||
Anderson, Chief Plant Systems | |||
(//r/tr | |||
C. J'. date | |||
Section, DRS | |||
Inspection Summan : Inspection on April 2s - May 3,1988 (Report No. | |||
j 50-353/88-12) | |||
Areas Inspected: Routine, onsite unannounced inspection by one region-based | |||
j inspector of activities pertaining to the safety-related electrical systems , | |||
and components. Specific areas reviewed included emergency diesel generator # | |||
maintenance,~ electrical construction inspection of wiring, cables, and | |||
components. | |||
Results: One violation was identified, 10 CFR 50, Appendix B, Criterion V; i | |||
lack of documented procedures and acceptance criteria for activities affecting | |||
quality in regards to maintenance of the emergency diesel generators. | |||
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8806010169 880525 | |||
PDR ADOCK 05000353 | |||
Q DCD , | |||
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DETAILS | |||
, | |||
1.0 -Persons Contacted | |||
1.1 Philadelphia Electric Company | |||
*J. Corcoran, Manager Quality Assurance | |||
J. Milito, Superintendent Start-up Support | |||
*D. DiPalo, Superintendent, Quality Assurance | |||
' | |||
*T. Tucker, Assistant Superintendent, Quality Assurance | |||
*K. Meck, Assistant Superintendent, Quality Assurance | |||
*F. Valentino, Construction Branch Manager | |||
T. Dey, Quality Assurance Engineer | |||
L. Dyer, Quality Assurance Engineer | |||
J. Higgins, Electrical Field Engineering | |||
*G. Lauderback, Supervisor Start-up Quality Assurance i | |||
*M. Teller, Construction Engineer | |||
1.2 Bechtel Construction Incorporated . | |||
H. Lilligh, Quality Assurance Manager | |||
W. Hatton, Quality Assurance Engineer | |||
*B. Foote, Quality Assurance Engineer | |||
*G. Kelly, Quality Assurance Engineer | |||
D. Jefferson, Quality Assurance Engineer | |||
N..Roy, Electrical Engineer | |||
- | |||
J. Hanze, Quality Control Inspector | |||
j J. Smith, Electrical Superintendent , | |||
*D. Moyer, Meehanical Engineer ! | |||
*K. Stout, Quality Control Engineer | |||
*D. Yenson, Field Engineer ' | |||
1.3 Colt Industries | |||
P | |||
J. Schroeder, Field Services Engineer | |||
1.4 U.S. Nuclear Regulatory Commission | |||
R. Gramm, Senior Resident Inspector | |||
*R. Fuhremister, Resident Inspector | |||
* Denotes those prescnt during the exit meeting. | |||
-_ | |||
.1 - . | |||
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3 | |||
2.0 Purpose and Scope | |||
.The purpose of this inspection was to ascertain that the safety-related | |||
electrical wiring, cable,-electrical components.and systems that are in | |||
various stages of construction / installation completion are specified, | |||
procured, installed, maintained, tested and inspected / controlled in such | |||
a manner that they will-perform their -required safety functions. The | |||
scope of this inspection was limited to: the 4160 volt power cable re- , | |||
placement installation for the "B" emergency diesel generator; pre-operational , | |||
maintenance of the emergency diesel generators; addressing a licensee | |||
identified problem in the 480V Cutler Hammer motor control centers; and | |||
the electrical construction "blue tag" completion / turn-over procedures. | |||
3.0 Procedures | |||
. | |||
The licensee documents relating to the final construction electrical | |||
check-out (blue tagging), the emergency diesel generator installation | |||
maintenance, and electrical caole installation were reviewed. These | |||
documents included construction specifications, drawings, work and * | |||
inspection procedures, and inspection / acceptance criteria. | |||
The review was made to determine whether the technical and administrative , | |||
requirements of the licensee's FSAR and the NRC requirements had been ! | |||
adequately translated into applicable documents to provide for adequate ' | |||
work performance and control. | |||
The specific documents reviewed for this inspection are listed in | |||
Appendix A. | |||
1 | |||
A deficiency was noted regarding inadequate diesel generator maintenance ' | |||
procedure, see section 4.1. | |||
4.0 Electrical Systems and Components | |||
4.1 Emergency Diesel Generators | |||
The four Limerick Unit 2 emergency diesel generators are the twelve i | |||
' | |||
cylinder Colt /Fairbanks-Morse 81/8 opposed piston type. These units | |||
have been stored in place for several years without operation. Due to | |||
the extensive storage period, the manufacturer recommended (by letter | |||
dated Febr'tary 16,1988) twelve items of inspections, maintenance and | |||
corrective actions which should be performed prior to engine startup. | |||
These recommendations included the following: | |||
- | |||
Due to the possibility of chemical action between the crankshafts | |||
and aluminum bearings, the main and connecting rod bearings should | |||
be replaced and the crankshaft journals relapped. | |||
-_ _. _ - _ . | |||
. | |||
s . | |||
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. | |||
1 | |||
. 4 | |||
- | |||
Inspect cylinder liner bores. | |||
- | |||
Replace generator end bearing. | |||
- | |||
Flush and inspect engine jacket water, fuel' intercooler, and | |||
lubricating oil systems. | |||
- | |||
Hydrostatically test engine jacket water system. - | |||
- | |||
Clean engine lubricating oil pan, fill engine system with oil and | |||
inspect all engine lubrication pressure points. | |||
- | |||
Inspect engine turbochargers. | |||
- | |||
Clean preservative from fuel injection compartment. | |||
- | |||
Remove and test all fuel injection nozzles. | |||
' | |||
. | |||
- | |||
Flush engine governors. | |||
- | |||
Check engine alignment. | |||
- | |||
Remove and inspect tappet assemblies of cylinders positioned at high , | |||
Cam. | |||
The licensee had engaged the services of the manufacturer's (Colt) field | |||
service representatives for the lead direction and supervision of the work | |||
associated with the main and connecting rod engine bearings replacement | |||
which was in progress at the time of this inspection. Personnel were | |||
provided by Bechtel to perform the work in accordance with directions, | |||
training and procedures to be suppiied by Colt. Continuous QC surveil- : | |||
lance inspection of the work was performed by bechtel/ licensee personnel. : | |||
This inspection determined that the replacement of the EDG bearings was | |||
being performed by the licensee in accordance with the following: | |||
- | |||
Modification Rework (HWR) packages 2AG 501-16, Revision 0 dated | |||
March 28, 1988 (This MWR is for the A EDG, the B, C, and D EDG MWR | |||
packages are the same). These MWR packages include insert sheets | |||
E14, E15, E16 E17, G3 and G4 directly from the vendors manual | |||
covering the removal, inspection, and replacement of the main and | |||
connecting rod oearings (they do not include crankshaf t journal | |||
lapping procedure). | |||
- | |||
Verbal instructions from the vendor field services representative | |||
which included the following. | |||
Crankshaf t main, connecting rod and thrust bearing jo rnals | |||
' | |||
* | |||
lapping procedure. ; | |||
c | |||
. | |||
5 | |||
, r,,,,-p, --- ,- - -7,yy.- =- ,y,, , w .,,e*,,c_- - - - - 9 | |||
n +- ,,, - _. ,-----.,y -,y- - | |||
yy--. . - -, , , , . - - . - ,,-,c- - | |||
c7 | |||
s, , | |||
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* | |||
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-... | |||
5 | |||
*- Proper abrasive lapping material (Tinesaver Products Company | |||
c: Hard Metal Lapping Compound No. 111-Green Label). | |||
* Proper tools and aids for use in performing the-lapping and how | |||
.; to use them to achieve the desired bearing journal surface | |||
' | |||
finish. Journal finish acceptance criteria. | |||
* Precautions with regards to the preparation and use of the | |||
lapping abrasive. | |||
* Precautions to prever.t entry of the contaminating lapping | |||
material into other bearings, oil passageways, inverted piston | |||
skirts, and other areas adjacent to the work area. | |||
* Procedures and materials to be used to clean the lapping | |||
abrasive from the finished crankshaft journal and adjacent areas. | |||
Cleanliness acceptance criteria (How much if any residual * | |||
lapping compound is acceptable). | |||
* Proper lubricant and procedure for application to tha lapped | |||
bearing journals and new bearings prior to asseably. | |||
* Engine oil passageways, hold-up volumes, and sumps cleaning | |||
following bearing replacements. | |||
At the time of this inspection the licensee had completed bearings | |||
replacement in the "A" and "C" EDG units and the "B" EDG was in the | |||
proce:s of rework / replacement. Erior to this inrpection, a problem was | |||
identified relative to lapping c.ompound-related bearing daeage in these | |||
same type Fairbanks Morse EDG units at the Getroit Edison Fermi Unit 2 | |||
Plant. N'': Inspection Report No. 50-341i J46 includes a Franklin | |||
Research report of Fairbanks Morse EDG bearing failures at the Fermi | |||
Unit 2 Plant. One of the fit, dings in this report was betring damage | |||
from crankshaft journal lapping compound, Independent evaluation of the | |||
bearing failures at Fermi's Unit 2 was conducted by Batelle and reported ~ | |||
to Detroit Edison on August 31, 1986. Included in this report were find- | |||
ings of bearing damage from journal lapping compounri and a recommendation | |||
to "Improve the method used to remove lapping compound from the crankshaft | |||
journal surfaces." Failure Analysis Asiociates investigation of the | |||
Fairbanks Morse EDG bearing problems re, sort was made to Detroit Edison | |||
during June 1986. It includes the following report paragraph. "The | |||
abrasive component of the bearing conditioner, the Timesaver Lapping | |||
Compound No. 111, was found to have particles up to .002 inch in | |||
diameter. The primary chenical component of the lapping compound is | |||
silica, a hard abrasive material. The presence of these hard particles | |||
in the bearing clearance will cause scratching and scoring of the bearing | |||
surfaces, friction causing excessive heat and thinning of the oil, and can | |||
contribute to breakdown of the oil film and seizure of ths bearing to the | |||
crankshaft." | |||
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An initial review of the Limerick Unit 2 EOG bearing replacement was | |||
conducted with the cognizant ifcensee QA personnel in order to review the | |||
status of the work, the personnel involved in performing the work, the | |||
procedures under which the work was being performed, and the Quality | |||
Assurance Surveillance Inspection program for this work including the | |||
acceptance criteria for the work. Initial concern was expressed by the | |||
inspector since there were no explicit written procedures for performing | |||
, the bearing journals lapping work. The operation including precautions | |||
and acceptance criteria are based upon verbal direction from the vendor | |||
field service representatives. Training of personnel in the work pro- ' | |||
cedures and acceptance criteria was hands on and word of mouth type train- | |||
ing. Initial concern was expressed by the inspector to the licensee QA | |||
representative relative to previous problems with connecting rod and main | |||
engine bearings in these same t/pe of EDG units at other plants. The | |||
concerns included those from the Fermi Unit 2 bearing failures in identical | |||
Fairbanks Morse EDG units. Some of the causes of beering damage were | |||
discussed irscluding damage caused by the improper emoval of lapping | |||
comoound (wher, reworking bearings). | |||
The license stated that the procedure in use for removing the lapping , | |||
compound is to wipe the journal clean with a reg soaked with varsol. A | |||
visual observation and/or rag wipe by the QA inspector is made to vuify | |||
proper removal. | |||
An inspection of the "D" diesel bearings replacement was made of the | |||
removed bearings including the Number 3 connecting rod bearing. A | |||
st.bstantial quantity of the lapping compound (approximctely one teaspoon | |||
full) was observed on the face of this bearing. Sinca this bearing had | |||
, not bun reworked, investigation was made by the licensee to determine the | |||
; source of the contaminating lapping compound. Determination was made that | |||
the lapping compound had either flowed through the oil passage from the | |||
adjacent Number 3 main baaring which had been recently lapped or it had | |||
j been accidentally dropped onto the bearing after removal. This finding | |||
. | |||
raised questions relative to reworked /new bearings possibly having sub- | |||
l stantial quantities of lapping compound ir, them from adjacent bearings | |||
! through the connecting oil passageways. Seve-al upper crankshaft main and | |||
i connecting rod becrings were disassembled and all were found to have rmall | |||
l | |||
quantities of the lapping compound in them. However the new number 10 | |||
upper main bearing was found with a substantial amount of lapping material | |||
in it. The entire surface of this bearing was scratched by the lapping | |||
j compound. Apparently the small amount of manual barring (turning) of the | |||
engine while lapping other bearings had been sufficient to cause darage to | |||
this bcaring because of tb ccataminating lapping compound left in it. It | |||
was at the point that all inarings in the engine became suspect fc:' | |||
contamination. | |||
As a consequence of these findings, the licensee took immediate actions | |||
t including the fNiowing: : | |||
l | |||
l | |||
- | |||
The bearing journal lapping operation was stopped. | |||
l | |||
l | |||
. | |||
p nr- --w -.r.- ,r.w-vy ,y- ,...,.--e ,my.e..pw | |||
9 , y w ----c-wy,-w,w, | |||
y ,_w.p ----33' | |||
, , , +--w g g-rv=-- . ----gg wTw* *NPP'"" +Y | |||
. . . . - , - . - - . . | |||
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7 | |||
- | |||
- The proper procedures for lapping and cleaning the bearing journals | |||
were discussed by the licensee with the Fairbanks Morse field | |||
> | |||
service representative. It included a proper sequence of work, | |||
plugging of oil passageways and acceptance criteria. Craft and | |||
quality assurance personnel were instructed by the Fairbanks Morse | |||
and licensee personnel. | |||
- | |||
Borescope inspections were made of several upper connecting rod | |||
lubrication passages from the crankshaft journal bearing area down to | |||
the piston wrist pin bearing ("D" EDG unit). No contamination was | |||
observed. | |||
- | |||
All "D" EDG unit crankshaf t main and connecting rod bearings were | |||
disassembled. All bearing surfaces were cleaned with fuel oil, | |||
inspected to the new zero-residual-lapping compound criteria, and | |||
the bearings were.then re-assembled. The damaged new Number 10 main | |||
bearing was replaced with another new bearing. | |||
There are twenty four connecting rod and twenty six main bearings in | |||
each EDG engine. Sample inspections of two bearings in each engine were | |||
' | |||
made for residual lapping compound contamination in the reworked "A" and | |||
" | |||
C" EDG units to establish a basis to either accept "As-Is," to expand the | |||
inspection scope for a greater confidence level, or to remove all bearings | |||
and c7ean (the same as EDG "D",1 Lower main bearings number 8 and 10 on | |||
the "A" unit and numbers 5 and 9 on the "C" unit were inspected. The ! | |||
selection of these particular bearings was made because it allowed | |||
inspection of work by both shifts of craftsmen and Q-C inspectors under | |||
the direction of the two different Fairbanks Morse field service repre- | |||
sentative. ~Basod upon these inspections, the licensee decided to accept | |||
. the "A" and "C" EDG units "As-Is." | |||
Interviews were conducted with several of the crafts and Q-C personnel | |||
directly involved in the performance of tais bearing replacement work. | |||
The bearings replacement work is beiag performed by journeyman millwrights. | |||
Lapping of shafts and journals, while not a frequent activity, is considered | |||
, a standard job function for the millwrights and is a standard job skill. | |||
' | |||
Two of the millwrights interviewed expressed considerable knowledge and | |||
, | |||
experience in the lapping of bearing journals. However they did not have | |||
previous experience with the Fairbanks Morse journal special finishing | |||
. requirements nor were they familiar with the type of lapping compound | |||
- being used. | |||
The inspector expressca further concern beyond the immediate EDG bearing | |||
rework / replacer..ent problems. This concern regards the lack of written | |||
procedures for performing the crankshaft lapping work which could | |||
accompany bearings inspection / replacement at any time during the life of | |||
the EDG units. These bearings are routinely inspected as 6 part of the | |||
. | |||
t | |||
, re - - , , - . - -.---a. , ,m,-4.,,,-c.-,vwvm.g , ,y.- -y,.,, w-..-,.w.mg-..w,.--r m-,m.mm.-,my.-..,my,wm eg m ,my , | |||
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8 | |||
18 month and 5 year surveillances which could involve resurfacing crank- | |||
shaft journals. Without detailed written ~ procedures to assure proper | |||
performance of this effort, including the removal of lapping abrasive | |||
contamination, the EDG bearings and other engine oil lubricated components | |||
are again subject to abrasive damage and possible failure. Further | |||
concern was also expressed for the adequate procedures and controls for | |||
the remaining eleven items of work covered by the Fairbanks Morse, | |||
February 16, 1988 letter. | |||
The lack /ebsence of these procedures both for the current bearing | |||
replacement as well as for bearing work during the life of the EDG units | |||
is a violation of Code of Federal Regulations 10 CFR 50, Appandix B | |||
Criterion V. This portion of the regulations requires the following: | |||
"Activities affecting quality shall be prescribed by documented instruc- | |||
tions, procedures, or drawings of a type appropriate to the circumstances | |||
and shall be accomplished in accordance with these instructions, proce- | |||
dures, or drawings. Instructions procedures, or drawings shall include | |||
appropriate quantitative or qualitative acceptance criteria for determining | |||
that important activities hava been satisfactorily accomplished." | |||
(50-353/88-12-01) | |||
4.2 Motor Control Centers (MCC) Supplied by Cutler Hammer (CH) | |||
4.2.1 Bus Overheating | |||
On April 15, 1988 the licensee reported that the potential exists | |||
for Cutler Hammer supplied MCC aluminum vertical bus bar sections to | |||
overheat thereby causing copper spring-loaded stab connections to | |||
the bus to deteriorate. The licensee report was based upon ex- | |||
perience with similar CH supplied MCC units at the Eddystone | |||
Generating Station (non-nuclear) and upon inforeation provided by | |||
CH. CH reported to the licensee that "the problem seems to be heat | |||
i build-up over a long time span which deteriorates the connection | |||
point between the copper stab and the vertical aluminum bus. The | |||
~ | |||
heat build-up seems to be caused by the aluminum bus not being a good | |||
enough heat sink to draw the heat away from these connection points. | |||
Aluminum will not disperse a concentrated heat point as rapidly as | |||
copper will due to the density differential in the two metals. This . | |||
problem has occur"ed before and the solution has been to change the | |||
I aluminum bus to copper bus in those sections containing size 4 | |||
starters only." | |||
, The licensee performed a visual inspection of all of the CH MCC | |||
Units in Unit 1 during the recent mini-outage. No evidence of | |||
contact burning or degradation was observed. Licensee engins.ering | |||
is currently conducting a study of all of the CH MCC Units and their | |||
loads in order to make an evaluation and establish recoa.mendations | |||
l | |||
for any actions required to resolve this potential problem. r | |||
, | |||
I | |||
e | |||
- - ,- .-- . , . . - - - - - - -.- - . . ~ . - , - . - -- | |||
- _ _ ---. | |||
, . | |||
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4 | |||
9 | |||
.., | |||
4.2.2 Defective Bellville Washers | |||
On April 15,1988 the licensee reported finding . multiple instances | |||
of. defective < cenical spring (Bellville) washers during B0P | |||
inspecticn of.CH MCC horizontal copper to vertical aluminum bus bar | |||
bolted connections. The Belleville washers are used to maintain | |||
proper bolted mating pressure between the main horizontal copper bus | |||
and thetindividual vertical aluminum bus sections. The failures | |||
observed consists of the washer becoming segmented by cracking from | |||
the outer to the inner edges. A washer in this condition could fail | |||
to properly maintain contact pressure between the two bus bars, | |||
allowing higher than designed resistance and eventual failure due to < | |||
overheating. Licensee metallurgicai examinations of the failed | |||
washers indicate.that improper process control during the plating | |||
: led to hydrogen embrittlement and failure of the washers during or | |||
shortly after tigntening. Both PECO and CH are conducting further | |||
evaluations to conclude root causes of the defects and failures and | |||
to assess their reportability. Disposition of this item to resolve | |||
the problem is dependant upon the licensees actions taken with regards | |||
to the aluminum bus bar heating problem discussed in paragraph 5.2.1. | |||
If the aluminum bus bar is replaced with copper, Belleville washers | |||
will not-be used. However if the bus bar is not replaced, the | |||
licensee is committed to take actions with regards to replacement of | |||
the washers. | |||
Licensee's actions for the foregoing items appear to be adequate. The | |||
inspector had no further questions at this time. , | |||
4.3 Electrical Power Cable | |||
On September 9s 1988 the licensee reported that the "B" Diesel Generator | |||
Power Cable had failed due to damage incurred while installing / pulling | |||
the cable. The damaged cable did not pass the installation megger test | |||
and requires replacement. The licensee reported that the cable was | |||
4 | |||
damaged while pulling out of one concrete sleeve and into another : | |||
because of the sharp bending radius and the sharp / abrasive edges on the ; | |||
concrete sleeves. | |||
The licensee has re-evaluated the cable pull and has chipped away some of | |||
the outer edge of the concrete sleeves to permit easier transition of the | |||
cable out of/into the sleeves. Based upon the licensees cable pulling | |||
tension calculation E-622, Revision 0 dated April 26, 1988, it appeared | |||
that the pull can be made without exceeding the maximun pull tension and l | |||
side wall pressura permitted for the types of cable. An independent NRC r | |||
calculation was made of the first segment of the pull in order to verify | |||
the licensee's calculation E-622. | |||
The pulling route and pulling procedures were thoroughly reviewed with | |||
the licensee both in the office and along the pulling route. (Procedures | |||
, | |||
d | |||
.. , , , .,_m, ,,__ me, ,m-_.,,,._~._,e,-, -,,---.-,.m ,-m . . ~ , , , , _ . - . . , , , , | |||
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--,-,_.- ,m ---3---m - ,--- --- | |||
,<-.. -- | |||
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10 | |||
t and calculations reviewed are listed in the Appendix to this report.) On | |||
May 3, 1988 the inspector witnessed the successfull pull of the first | |||
segment of the replacement cable and monitored the pulling tension during | |||
r, the pull. The maximum tension measured.was 1050 pounds. This compared | |||
c | |||
', favorably with tha maximum calculated expected tension of 2141 pounds and | |||
the maximum allowable tension of 3604 pounds. Inspection was made of the | |||
oulling devicas including the tuggers, the mares tail, cable attachment, | |||
.' proper minfeum bend radius templates and the currdat calibration of the | |||
tension meter. Nf discrepancies were observed in either the cable pulling | |||
procedures, calculations, or in the actual cable puil. | |||
4.4 Electrical Construction Final Inspection for Turn-Over to Start-Up | |||
A review inspection was made of the licensee's program for "Blue Tagging" | |||
electrical components, sub-systems and systems for construction - | |||
completion /verificaticn and turn-over to start-up for pre-operational | |||
tests. The inspection consisted of a review of licensee's procedures, | |||
personnel qualification, and field verification of the implementation of | |||
the procedures. Procedures and documents reviewed are listed in the | |||
Appendix to this report. | |||
An inspection was made of the licensee's blue tag verifications which | |||
were in progress for the emergency diesel generator engine starting | |||
controls in panel 2ETB-AG-501. The drawings in use were verified as the ! | |||
latest issue in effect of Colt Industries drawing 11870038 sheets 1-6. | |||
Two inspectors were observed in the process of performing verification of | |||
some of the alarm and annunicator circuits in an alarm and annunicator | |||
panel. The inspectors were observed physically tracing each wire within | |||
the panel to and through each connection and component. The wiring was | |||
verified as to type, size,4dentifications, (arminations and routing. | |||
Each component (relay, switch, terminal block, transformer, etc.) was also | |||
verified. Each wiring circuit was meggered to ensure wiring integrity. | |||
As each wire and component. were verified they were yellowed out on the | |||
drawing. Inspector responses to questions indicated a good understanding | |||
. and knowledge of the work being performed. Their qualifications were | |||
found to be current in accordance with Licensee Qualification Procedure | |||
EE 2.1. | |||
. | |||
A review was made of completed and partially completed blue tag inspection | |||
. drawings and records. Each of the drawings and records examined were | |||
1 | |||
found to be in order with appropriate sign-offs and approvals. | |||
The blue tag inspection / verifications are not normally witnessed by Q-C l | |||
' | |||
personnel. However periodic audits are performed to verify that the | |||
inspections are conducted and documented in &ccordance with the latest , | |||
approved procedures and drawings. A review was made of pECO Audit | |||
Reports AR-2E-227 dated May 5, 1986 and AR-2S-074 dated March 7, 1988. | |||
Except for minor documentation problems, there was no adverse audit | |||
findings. | |||
! | |||
* | |||
k | |||
. | |||
.) - | |||
, - ~ . - . , - , . _ .~,_,m-- , _ , - , , . - - - . . - - , , _ _ . _ . . - - - - - - - _ _ . , . , . _ - , - . . _ - . . - , , - | |||
_ _ _ _ _ _ _ _ _ _ | |||
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11 | |||
; E< . | |||
5.0 Exit Interview | |||
An exit interview was held on Mav 3, 1988 with members of the licensee | |||
stafi, denoted in paraaraph 1, at the conclusion of the inspection. The | |||
inspector summarized the scope and findings of the inspection at that | |||
time. | |||
No written material was provided to the licensee, | |||
>- | |||
T | |||
l | |||
!/ | |||
si | |||
' | |||
, i | |||
i | |||
, | |||
. | |||
. | |||
, . | |||
M- f' l ': k | |||
. | |||
.- | |||
* | |||
rc : | |||
-f | |||
Appendix A : | |||
Documents Reviewed l | |||
! | |||
1.0 ' Final Safety Analysis Report Chapter 8, Electric Power ' | |||
2.0' Construction Procedures | |||
E-2 Peimanent Plant Cable Installation and Termination . | |||
- G-3 Long Term Storage / Maintenance / Lubrication of Permanent Plant | |||
- | |||
Equipment and Material Prior to Turnover | |||
4 | |||
. | |||
E-622 Cable Pulling Calculation for Repull of Cable 2B6501A ; | |||
- | |||
- | |||
E-1412- Wire and Cable, Notes and Details | |||
< | |||
M-1 Modification / Rework Packtge MRP 246501-16 to Replace the Diesel , | |||
Generator Bearings | |||
3.0 Field Engineering Procedures (Blue Tag) | |||
FE-34 Procedure to Inspect and Test 480 VAC Load Center Breakers , | |||
FE-40 Procedure to Inspect a i Test Medium Voltage Circuit Breakers , | |||
EE-11.11 Inspection and Testing Procedure Implementation | |||
EE 2.1 Procedure for the Qualification of Fie?d Engineers Assigned to | |||
, Nuclear Power Plants | |||
EE2 1-I Personnel Quali'ication Reccrds of Field Engineers Assigned to ' | |||
. | |||
a Nuctaar Power Plant (Including Unit 2 List of Personnel and | |||
theirijualification). | |||
.EE6.3 Procedure to Control Design Documents'used for Insp:-tion and | |||
Test Activities | |||
3 | |||
4.0 Quality Assurance | |||
2E-213 Quality Assurance Surveillance Check Report Verification of | |||
. Cable Pulling Tension Calculation | |||
. | |||
.25-074 Audit Report of PECo Electric Field Engineering Blue Tag | |||
Testing of Safeguard 440 Volt Load Centers | |||
2E-227 Audit Report Inspection of Cutler Hammer Motor Control Center ; | |||
20E224 . | |||
- -. _ . . _ _ . . _ _ - . - _ _ .--- _ _ _ . _ _ _,_ -_, , _ _ . _ _ ~ - . ~ _ _ . . _ .i | |||
__ _ _ _ | |||
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. . | |||
. | |||
, | |||
Appendix A 2 | |||
5.0 NRC Reports m | |||
50-341/85-046 Inspection Report of the Detroit Edison Fermi | |||
Nuclear Power Plant Plant, Unit 2 Emergency Diesel | |||
Generator Bearing Failures, July 3,1986. | |||
6.0 Consultants Reports | |||
Franklin Research Center Report to USNRC - Evaluation of Bearing | |||
Failures in Fairbanks Morse Diesel Engines at the Enrico Fermi Unit 2 | |||
Reactor, March 3, 1986. | |||
Battelle Final Report to Detroit Edison - A Metallurgical Investigation | |||
of Various Defect on the Surfaces of Diesel Engine Aluminium-Tin | |||
Bearings, August 31, 1986. | |||
Failure Analysis Associates Report to Detroit Edison - Investigation of | |||
Surface Scoring of Main Bearings: Fairbanks Morse 38T08-1/8 Diesels at | |||
Farmt II Power Plant, June 1986. Report FAA-0C-d-86-06-03. | |||
. . . . . . . . - - - - - - - _ - - -.----a | |||
}} |
Latest revision as of 16:18, 2 January 2021
ML20154M087 | |
Person / Time | |
---|---|
Site: | Limerick |
Issue date: | 05/18/1988 |
From: | Anderson C, Woodard C NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
To: | |
Shared Package | |
ML20154M043 | List: |
References | |
50-353-88-12, NUDOCS 8806010169 | |
Download: ML20154M087 (13) | |
See also: IR 05000353/1988012
Text
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U.S. NUCLEAR REGULATORY COMMISSION
-REGION I'
Report No. 50-353/88-12
Docket No. 50-353
License No. CPPR-107 Priority -
Category B
- - Licensee
- Philadelphia Electric Company
2301 Market Street
Philadelphia, PA -19101
Fa:ility Name: Limerick Nuclear Generating Station, Unit 2
Inspection At: Limerick, Pennsylvania
8
Inspection Conducted: April 25 - May 3, 1988
-Inspector: O/0 L C. Cbbrd
C. H. Woodard, Reactor Engineer
r[n[if
date
Approved by: O
Anderson, Chief Plant Systems
(//r/tr
C. J'. date
Section, DRS
Inspection Summan : Inspection on April 2s - May 3,1988 (Report No.
j 50-353/88-12)
Areas Inspected: Routine, onsite unannounced inspection by one region-based
j inspector of activities pertaining to the safety-related electrical systems ,
and components. Specific areas reviewed included emergency diesel generator #
maintenance,~ electrical construction inspection of wiring, cables, and
components.
Results: One violation was identified, 10 CFR 50, Appendix B, Criterion V; i
lack of documented procedures and acceptance criteria for activities affecting
quality in regards to maintenance of the emergency diesel generators.
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8806010169 880525
PDR ADOCK 05000353
Q DCD ,
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DETAILS
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1.0 -Persons Contacted
1.1 Philadelphia Electric Company
- J. Corcoran, Manager Quality Assurance
J. Milito, Superintendent Start-up Support
- D. DiPalo, Superintendent, Quality Assurance
'
- T. Tucker, Assistant Superintendent, Quality Assurance
- K. Meck, Assistant Superintendent, Quality Assurance
- F. Valentino, Construction Branch Manager
T. Dey, Quality Assurance Engineer
L. Dyer, Quality Assurance Engineer
J. Higgins, Electrical Field Engineering
- G. Lauderback, Supervisor Start-up Quality Assurance i
- M. Teller, Construction Engineer
1.2 Bechtel Construction Incorporated .
H. Lilligh, Quality Assurance Manager
W. Hatton, Quality Assurance Engineer
- B. Foote, Quality Assurance Engineer
- G. Kelly, Quality Assurance Engineer
D. Jefferson, Quality Assurance Engineer
N..Roy, Electrical Engineer
-
J. Hanze, Quality Control Inspector
j J. Smith, Electrical Superintendent ,
- D. Moyer, Meehanical Engineer !
- K. Stout, Quality Control Engineer
- D. Yenson, Field Engineer '
1.3 Colt Industries
P
J. Schroeder, Field Services Engineer
1.4 U.S. Nuclear Regulatory Commission
R. Gramm, Senior Resident Inspector
- R. Fuhremister, Resident Inspector
- Denotes those prescnt during the exit meeting.
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2.0 Purpose and Scope
.The purpose of this inspection was to ascertain that the safety-related
electrical wiring, cable,-electrical components.and systems that are in
various stages of construction / installation completion are specified,
procured, installed, maintained, tested and inspected / controlled in such
a manner that they will-perform their -required safety functions. The
scope of this inspection was limited to: the 4160 volt power cable re- ,
placement installation for the "B" emergency diesel generator; pre-operational ,
maintenance of the emergency diesel generators; addressing a licensee
identified problem in the 480V Cutler Hammer motor control centers; and
the electrical construction "blue tag" completion / turn-over procedures.
3.0 Procedures
.
The licensee documents relating to the final construction electrical
check-out (blue tagging), the emergency diesel generator installation
maintenance, and electrical caole installation were reviewed. These
documents included construction specifications, drawings, work and *
inspection procedures, and inspection / acceptance criteria.
The review was made to determine whether the technical and administrative ,
requirements of the licensee's FSAR and the NRC requirements had been !
adequately translated into applicable documents to provide for adequate '
work performance and control.
The specific documents reviewed for this inspection are listed in
Appendix A.
1
A deficiency was noted regarding inadequate diesel generator maintenance '
procedure, see section 4.1.
4.0 Electrical Systems and Components
4.1 Emergency Diesel Generators
The four Limerick Unit 2 emergency diesel generators are the twelve i
'
cylinder Colt /Fairbanks-Morse 81/8 opposed piston type. These units
have been stored in place for several years without operation. Due to
the extensive storage period, the manufacturer recommended (by letter
dated Febr'tary 16,1988) twelve items of inspections, maintenance and
corrective actions which should be performed prior to engine startup.
These recommendations included the following:
-
Due to the possibility of chemical action between the crankshafts
and aluminum bearings, the main and connecting rod bearings should
be replaced and the crankshaft journals relapped.
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Inspect cylinder liner bores.
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Replace generator end bearing.
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Flush and inspect engine jacket water, fuel' intercooler, and
lubricating oil systems.
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Hydrostatically test engine jacket water system. -
-
Clean engine lubricating oil pan, fill engine system with oil and
inspect all engine lubrication pressure points.
-
Inspect engine turbochargers.
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Clean preservative from fuel injection compartment.
-
Remove and test all fuel injection nozzles.
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Flush engine governors.
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Check engine alignment.
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Remove and inspect tappet assemblies of cylinders positioned at high ,
Cam.
The licensee had engaged the services of the manufacturer's (Colt) field
service representatives for the lead direction and supervision of the work
associated with the main and connecting rod engine bearings replacement
which was in progress at the time of this inspection. Personnel were
provided by Bechtel to perform the work in accordance with directions,
training and procedures to be suppiied by Colt. Continuous QC surveil- :
lance inspection of the work was performed by bechtel/ licensee personnel. :
This inspection determined that the replacement of the EDG bearings was
being performed by the licensee in accordance with the following:
-
Modification Rework (HWR) packages 2AG 501-16, Revision 0 dated
March 28, 1988 (This MWR is for the A EDG, the B, C, and D EDG MWR
packages are the same). These MWR packages include insert sheets
E14, E15, E16 E17, G3 and G4 directly from the vendors manual
covering the removal, inspection, and replacement of the main and
connecting rod oearings (they do not include crankshaf t journal
lapping procedure).
-
Verbal instructions from the vendor field services representative
which included the following.
Crankshaf t main, connecting rod and thrust bearing jo rnals
'
lapping procedure. ;
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- - Proper abrasive lapping material (Tinesaver Products Company
c: Hard Metal Lapping Compound No. 111-Green Label).
- Proper tools and aids for use in performing the-lapping and how
.; to use them to achieve the desired bearing journal surface
'
finish. Journal finish acceptance criteria.
- Precautions with regards to the preparation and use of the
lapping abrasive.
- Precautions to prever.t entry of the contaminating lapping
material into other bearings, oil passageways, inverted piston
skirts, and other areas adjacent to the work area.
- Procedures and materials to be used to clean the lapping
abrasive from the finished crankshaft journal and adjacent areas.
Cleanliness acceptance criteria (How much if any residual *
lapping compound is acceptable).
- Proper lubricant and procedure for application to tha lapped
bearing journals and new bearings prior to asseably.
- Engine oil passageways, hold-up volumes, and sumps cleaning
following bearing replacements.
At the time of this inspection the licensee had completed bearings
replacement in the "A" and "C" EDG units and the "B" EDG was in the
proce:s of rework / replacement. Erior to this inrpection, a problem was
identified relative to lapping c.ompound-related bearing daeage in these
same type Fairbanks Morse EDG units at the Getroit Edison Fermi Unit 2
Plant. N: Inspection Report No. 50-341i J46 includes a Franklin
Research report of Fairbanks Morse EDG bearing failures at the Fermi
Unit 2 Plant. One of the fit, dings in this report was betring damage
from crankshaft journal lapping compound, Independent evaluation of the
bearing failures at Fermi's Unit 2 was conducted by Batelle and reported ~
to Detroit Edison on August 31, 1986. Included in this report were find-
ings of bearing damage from journal lapping compounri and a recommendation
to "Improve the method used to remove lapping compound from the crankshaft
journal surfaces." Failure Analysis Asiociates investigation of the
Fairbanks Morse EDG bearing problems re, sort was made to Detroit Edison
during June 1986. It includes the following report paragraph. "The
abrasive component of the bearing conditioner, the Timesaver Lapping
Compound No. 111, was found to have particles up to .002 inch in
diameter. The primary chenical component of the lapping compound is
silica, a hard abrasive material. The presence of these hard particles
in the bearing clearance will cause scratching and scoring of the bearing
surfaces, friction causing excessive heat and thinning of the oil, and can
contribute to breakdown of the oil film and seizure of ths bearing to the
crankshaft."
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An initial review of the Limerick Unit 2 EOG bearing replacement was
conducted with the cognizant ifcensee QA personnel in order to review the
status of the work, the personnel involved in performing the work, the
procedures under which the work was being performed, and the Quality
Assurance Surveillance Inspection program for this work including the
acceptance criteria for the work. Initial concern was expressed by the
inspector since there were no explicit written procedures for performing
, the bearing journals lapping work. The operation including precautions
and acceptance criteria are based upon verbal direction from the vendor
field service representatives. Training of personnel in the work pro- '
cedures and acceptance criteria was hands on and word of mouth type train-
ing. Initial concern was expressed by the inspector to the licensee QA
representative relative to previous problems with connecting rod and main
engine bearings in these same t/pe of EDG units at other plants. The
concerns included those from the Fermi Unit 2 bearing failures in identical
Fairbanks Morse EDG units. Some of the causes of beering damage were
discussed irscluding damage caused by the improper emoval of lapping
comoound (wher, reworking bearings).
The license stated that the procedure in use for removing the lapping ,
compound is to wipe the journal clean with a reg soaked with varsol. A
visual observation and/or rag wipe by the QA inspector is made to vuify
proper removal.
An inspection of the "D" diesel bearings replacement was made of the
removed bearings including the Number 3 connecting rod bearing. A
st.bstantial quantity of the lapping compound (approximctely one teaspoon
full) was observed on the face of this bearing. Sinca this bearing had
, not bun reworked, investigation was made by the licensee to determine the
- source of the contaminating lapping compound. Determination was made that
the lapping compound had either flowed through the oil passage from the
adjacent Number 3 main baaring which had been recently lapped or it had
j been accidentally dropped onto the bearing after removal. This finding
.
raised questions relative to reworked /new bearings possibly having sub-
l stantial quantities of lapping compound ir, them from adjacent bearings
! through the connecting oil passageways. Seve-al upper crankshaft main and
i connecting rod becrings were disassembled and all were found to have rmall
l
quantities of the lapping compound in them. However the new number 10
upper main bearing was found with a substantial amount of lapping material
in it. The entire surface of this bearing was scratched by the lapping
j compound. Apparently the small amount of manual barring (turning) of the
engine while lapping other bearings had been sufficient to cause darage to
this bcaring because of tb ccataminating lapping compound left in it. It
was at the point that all inarings in the engine became suspect fc:'
contamination.
As a consequence of these findings, the licensee took immediate actions
t including the fNiowing: :
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The bearing journal lapping operation was stopped.
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- The proper procedures for lapping and cleaning the bearing journals
were discussed by the licensee with the Fairbanks Morse field
>
service representative. It included a proper sequence of work,
plugging of oil passageways and acceptance criteria. Craft and
quality assurance personnel were instructed by the Fairbanks Morse
and licensee personnel.
-
Borescope inspections were made of several upper connecting rod
lubrication passages from the crankshaft journal bearing area down to
the piston wrist pin bearing ("D" EDG unit). No contamination was
observed.
-
All "D" EDG unit crankshaf t main and connecting rod bearings were
disassembled. All bearing surfaces were cleaned with fuel oil,
inspected to the new zero-residual-lapping compound criteria, and
the bearings were.then re-assembled. The damaged new Number 10 main
bearing was replaced with another new bearing.
There are twenty four connecting rod and twenty six main bearings in
each EDG engine. Sample inspections of two bearings in each engine were
'
made for residual lapping compound contamination in the reworked "A" and
"
C" EDG units to establish a basis to either accept "As-Is," to expand the
inspection scope for a greater confidence level, or to remove all bearings
and c7ean (the same as EDG "D",1 Lower main bearings number 8 and 10 on
the "A" unit and numbers 5 and 9 on the "C" unit were inspected. The !
selection of these particular bearings was made because it allowed
inspection of work by both shifts of craftsmen and Q-C inspectors under
the direction of the two different Fairbanks Morse field service repre-
sentative. ~Basod upon these inspections, the licensee decided to accept
. the "A" and "C" EDG units "As-Is."
Interviews were conducted with several of the crafts and Q-C personnel
directly involved in the performance of tais bearing replacement work.
The bearings replacement work is beiag performed by journeyman millwrights.
Lapping of shafts and journals, while not a frequent activity, is considered
, a standard job function for the millwrights and is a standard job skill.
'
Two of the millwrights interviewed expressed considerable knowledge and
,
experience in the lapping of bearing journals. However they did not have
previous experience with the Fairbanks Morse journal special finishing
. requirements nor were they familiar with the type of lapping compound
- being used.
The inspector expressca further concern beyond the immediate EDG bearing
rework / replacer..ent problems. This concern regards the lack of written
procedures for performing the crankshaft lapping work which could
accompany bearings inspection / replacement at any time during the life of
the EDG units. These bearings are routinely inspected as 6 part of the
.
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18 month and 5 year surveillances which could involve resurfacing crank-
shaft journals. Without detailed written ~ procedures to assure proper
performance of this effort, including the removal of lapping abrasive
contamination, the EDG bearings and other engine oil lubricated components
are again subject to abrasive damage and possible failure. Further
concern was also expressed for the adequate procedures and controls for
the remaining eleven items of work covered by the Fairbanks Morse,
February 16, 1988 letter.
The lack /ebsence of these procedures both for the current bearing
replacement as well as for bearing work during the life of the EDG units
is a violation of Code of Federal Regulations 10 CFR 50, Appandix B
Criterion V. This portion of the regulations requires the following:
"Activities affecting quality shall be prescribed by documented instruc-
tions, procedures, or drawings of a type appropriate to the circumstances
and shall be accomplished in accordance with these instructions, proce-
dures, or drawings. Instructions procedures, or drawings shall include
appropriate quantitative or qualitative acceptance criteria for determining
that important activities hava been satisfactorily accomplished."
(50-353/88-12-01)
4.2 Motor Control Centers (MCC) Supplied by Cutler Hammer (CH)
4.2.1 Bus Overheating
On April 15, 1988 the licensee reported that the potential exists
for Cutler Hammer supplied MCC aluminum vertical bus bar sections to
overheat thereby causing copper spring-loaded stab connections to
the bus to deteriorate. The licensee report was based upon ex-
perience with similar CH supplied MCC units at the Eddystone
Generating Station (non-nuclear) and upon inforeation provided by
CH. CH reported to the licensee that "the problem seems to be heat
i build-up over a long time span which deteriorates the connection
point between the copper stab and the vertical aluminum bus. The
~
heat build-up seems to be caused by the aluminum bus not being a good
enough heat sink to draw the heat away from these connection points.
Aluminum will not disperse a concentrated heat point as rapidly as
copper will due to the density differential in the two metals. This .
problem has occur"ed before and the solution has been to change the
I aluminum bus to copper bus in those sections containing size 4
starters only."
, The licensee performed a visual inspection of all of the CH MCC
Units in Unit 1 during the recent mini-outage. No evidence of
contact burning or degradation was observed. Licensee engins.ering
is currently conducting a study of all of the CH MCC Units and their
loads in order to make an evaluation and establish recoa.mendations
l
for any actions required to resolve this potential problem. r
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4.2.2 Defective Bellville Washers
On April 15,1988 the licensee reported finding . multiple instances
of. defective < cenical spring (Bellville) washers during B0P
inspecticn of.CH MCC horizontal copper to vertical aluminum bus bar
bolted connections. The Belleville washers are used to maintain
proper bolted mating pressure between the main horizontal copper bus
and thetindividual vertical aluminum bus sections. The failures
observed consists of the washer becoming segmented by cracking from
the outer to the inner edges. A washer in this condition could fail
to properly maintain contact pressure between the two bus bars,
allowing higher than designed resistance and eventual failure due to <
overheating. Licensee metallurgicai examinations of the failed
washers indicate.that improper process control during the plating
- led to hydrogen embrittlement and failure of the washers during or
shortly after tigntening. Both PECO and CH are conducting further
evaluations to conclude root causes of the defects and failures and
to assess their reportability. Disposition of this item to resolve
the problem is dependant upon the licensees actions taken with regards
to the aluminum bus bar heating problem discussed in paragraph 5.2.1.
If the aluminum bus bar is replaced with copper, Belleville washers
will not-be used. However if the bus bar is not replaced, the
licensee is committed to take actions with regards to replacement of
the washers.
Licensee's actions for the foregoing items appear to be adequate. The
inspector had no further questions at this time. ,
4.3 Electrical Power Cable
On September 9s 1988 the licensee reported that the "B" Diesel Generator
Power Cable had failed due to damage incurred while installing / pulling
the cable. The damaged cable did not pass the installation megger test
and requires replacement. The licensee reported that the cable was
4
damaged while pulling out of one concrete sleeve and into another :
because of the sharp bending radius and the sharp / abrasive edges on the ;
concrete sleeves.
The licensee has re-evaluated the cable pull and has chipped away some of
the outer edge of the concrete sleeves to permit easier transition of the
cable out of/into the sleeves. Based upon the licensees cable pulling
tension calculation E-622, Revision 0 dated April 26, 1988, it appeared
that the pull can be made without exceeding the maximun pull tension and l
side wall pressura permitted for the types of cable. An independent NRC r
calculation was made of the first segment of the pull in order to verify
the licensee's calculation E-622.
The pulling route and pulling procedures were thoroughly reviewed with
the licensee both in the office and along the pulling route. (Procedures
,
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t and calculations reviewed are listed in the Appendix to this report.) On
May 3, 1988 the inspector witnessed the successfull pull of the first
segment of the replacement cable and monitored the pulling tension during
r, the pull. The maximum tension measured.was 1050 pounds. This compared
c
', favorably with tha maximum calculated expected tension of 2141 pounds and
the maximum allowable tension of 3604 pounds. Inspection was made of the
oulling devicas including the tuggers, the mares tail, cable attachment,
.' proper minfeum bend radius templates and the currdat calibration of the
tension meter. Nf discrepancies were observed in either the cable pulling
procedures, calculations, or in the actual cable puil.
4.4 Electrical Construction Final Inspection for Turn-Over to Start-Up
A review inspection was made of the licensee's program for "Blue Tagging"
electrical components, sub-systems and systems for construction -
completion /verificaticn and turn-over to start-up for pre-operational
tests. The inspection consisted of a review of licensee's procedures,
personnel qualification, and field verification of the implementation of
the procedures. Procedures and documents reviewed are listed in the
Appendix to this report.
An inspection was made of the licensee's blue tag verifications which
were in progress for the emergency diesel generator engine starting
controls in panel 2ETB-AG-501. The drawings in use were verified as the !
latest issue in effect of Colt Industries drawing 11870038 sheets 1-6.
Two inspectors were observed in the process of performing verification of
some of the alarm and annunicator circuits in an alarm and annunicator
panel. The inspectors were observed physically tracing each wire within
the panel to and through each connection and component. The wiring was
verified as to type, size,4dentifications, (arminations and routing.
Each component (relay, switch, terminal block, transformer, etc.) was also
verified. Each wiring circuit was meggered to ensure wiring integrity.
As each wire and component. were verified they were yellowed out on the
drawing. Inspector responses to questions indicated a good understanding
. and knowledge of the work being performed. Their qualifications were
found to be current in accordance with Licensee Qualification Procedure
EE 2.1.
.
A review was made of completed and partially completed blue tag inspection
. drawings and records. Each of the drawings and records examined were
1
found to be in order with appropriate sign-offs and approvals.
The blue tag inspection / verifications are not normally witnessed by Q-C l
'
personnel. However periodic audits are performed to verify that the
inspections are conducted and documented in &ccordance with the latest ,
approved procedures and drawings. A review was made of pECO Audit
Reports AR-2E-227 dated May 5, 1986 and AR-2S-074 dated March 7, 1988.
Except for minor documentation problems, there was no adverse audit
findings.
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5.0 Exit Interview
An exit interview was held on Mav 3, 1988 with members of the licensee
stafi, denoted in paraaraph 1, at the conclusion of the inspection. The
inspector summarized the scope and findings of the inspection at that
time.
No written material was provided to the licensee,
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Appendix A :
Documents Reviewed l
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1.0 ' Final Safety Analysis Report Chapter 8, Electric Power '
2.0' Construction Procedures
E-2 Peimanent Plant Cable Installation and Termination .
- G-3 Long Term Storage / Maintenance / Lubrication of Permanent Plant
-
Equipment and Material Prior to Turnover
4
.
E-622 Cable Pulling Calculation for Repull of Cable 2B6501A ;
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E-1412- Wire and Cable, Notes and Details
<
M-1 Modification / Rework Packtge MRP 246501-16 to Replace the Diesel ,
Generator Bearings
3.0 Field Engineering Procedures (Blue Tag)
FE-34 Procedure to Inspect and Test 480 VAC Load Center Breakers ,
FE-40 Procedure to Inspect a i Test Medium Voltage Circuit Breakers ,
EE-11.11 Inspection and Testing Procedure Implementation
EE 2.1 Procedure for the Qualification of Fie?d Engineers Assigned to
, Nuclear Power Plants
EE2 1-I Personnel Quali'ication Reccrds of Field Engineers Assigned to '
.
a Nuctaar Power Plant (Including Unit 2 List of Personnel and
theirijualification).
.EE6.3 Procedure to Control Design Documents'used for Insp:-tion and
Test Activities
3
4.0 Quality Assurance
2E-213 Quality Assurance Surveillance Check Report Verification of
. Cable Pulling Tension Calculation
.
.25-074 Audit Report of PECo Electric Field Engineering Blue Tag
Testing of Safeguard 440 Volt Load Centers
2E-227 Audit Report Inspection of Cutler Hammer Motor Control Center ;
20E224 .
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Appendix A 2
5.0 NRC Reports m
50-341/85-046 Inspection Report of the Detroit Edison Fermi
Nuclear Power Plant Plant, Unit 2 Emergency Diesel
Generator Bearing Failures, July 3,1986.
6.0 Consultants Reports
Franklin Research Center Report to USNRC - Evaluation of Bearing
Failures in Fairbanks Morse Diesel Engines at the Enrico Fermi Unit 2
Reactor, March 3, 1986.
Battelle Final Report to Detroit Edison - A Metallurgical Investigation
of Various Defect on the Surfaces of Diesel Engine Aluminium-Tin
Bearings, August 31, 1986.
Failure Analysis Associates Report to Detroit Edison - Investigation of
Surface Scoring of Main Bearings: Fairbanks Morse 38T08-1/8 Diesels at
Farmt II Power Plant, June 1986. Report FAA-0C-d-86-06-03.
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