IR 05000338/1987012
| ML20236B222 | |
| Person / Time | |
|---|---|
| Site: | North Anna  |
| Issue date: | 07/14/1987 |
| From: | Blake J, Robert Carrion, Economos N NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| To: | |
| Shared Package | |
| ML20236B210 | List: |
| References | |
| 50-338-87-12, 50-339-87-12, NUDOCS 8707290013 | |
| Download: ML20236B222 (14) | |
Text
r, UNITED STATES
-
/pn Mouq'o NUCLEAR REGULATORY COMMISSION
[$
-
$
REGION 11 I
y, fj 101 MARIETTA STREET, N.W.
]
"*
ATLANTA. GEORGI A 30323
,o 9 *****
{
Report Nos.:
50-338/87-12 and 50-339/87-12 Licensee:
Virginia Electric and Power Company
j Richmond, VA 23261 Docket Nos.:
50-338 and 50-339 License Nos.:
NPF-4 and NPF-7 Facility Name:
North Anna 1 and 2 l
Inspection Con ucted:
May 4-8, 18-22, 1987 and June 3-5, 1987 I
Inspecto s:-
/7 N.
oWomo Dst $1 ned
'
2 M 47 R.
arrion Date' Signed
~
.
Approv d b -
f
J /~. Blake, Section Chief Bate Signed n/jineering Branch Division of Reactor Safety SUMMARY Scope:
This routine, announced inspection was conducted in the areas of licensee action on previous open items; isiservice inspection activities, e.g.,
Ultrasonic (UT) examination of safety-related piping, Eddy Current (EC)
examination of Steam Generator (SG) tubing; functional testing of hydraulic snubbers; secondary side pipe UT examination and pipe replacement; flux thimble inspection; recirculation spray heat exchanger diaphragm plate installation; pressurizer safety and relief valve discharge pipe support modifications.
Results:
One violation was identified:
Failure to Maintain Control of Safety-Related (SR) Materials, paragraph 7.
8707290013 870721
{DR ADOCK 05000338 PDR t
... _ _.. _ _. - _ _ _ _ _. _ _ _ _. _ _. _ _
_ _ _ _ _ _ _ _ _
.
.
REPORT DETAILS
.!
1.
Persons Contacted l
Licensee Employees
!
- E. Harrell, Station Manager
- E. Smith, Jr., Assistant Station Manager
- M. Bowling, Assistant Station Manager
- A. Stall, Superintendent Technical Services
..
'
- L. N. Hartz, ISI Supervisor, North Anna Power Station
- J. H. Liberstien, Site Licensing Engineer
- T.. Johnson, Quality Assurance Supervisor
- J. E. Wroniewicz, Supervisor Site Engineering q
T. Sweeney, Site Engineering Office Engineer q
- G. Harkness, Station Engineering Office Engineer M. R, Kansler, Superintendent Maintenance
- H. L. Travis, Supervisor, Nondestructive Examinations (NDE)
.
- R. F. Driscoll, Manager Quality Assurance
T. M. McLaughlin, System Maintenance Support, (SMS) Foreman
M. L. Walker, SMS Foreman
M. Adams, Supervisor Plant Engineer P. Boulden, Lead Electrical Engineer, Plant Engineering l
J. E. Egan, Instructor, Mechanical
]
i Other Organizations
]
Technicon Enterprises, Inc. (TEI)
Mike Sedlack, Consultant i
Westinghouse, (W) Nuclear Services Integration Division i
'
R. Hilderman, ISI Coordinator
'
Other licensee employees contacted included QC/QA inspectors, technicians, and office personnel.
NRC Resident Inspectors
- J. Caldwell, Ser,ior Resident Inspector L. King, Resident Inspector
- Attended exit interview 2.
Exit Interview The inspection scope and findings were summarized on May 22, and June 5, 1987, with those persons indicated in paragraph 1 above. The inspectors described the areas inspected and discussed in detail the inspection findings.
No dissenting comments were received from the licensee.
_ _ _ _ _ _ _ _ - _ _ _ _ _ - _ - _ _ _ _ _ _ _ _ _ _ _ _ _ _
_
-
._-_-__-__-_______-___a
- _ - _
-__
_ _ -
._
.
-
.
.,
(0 pen)
Violation 338/87-12-01, Failure to Maintain Control of Safety-Related Materials, paragraph 7.
(0 pen) Inspector Followup Item (IFI) 338-87-12-02, Apparent Base Metal Indication, Hanger Weld SHP-R-305, paragraph 6.c.
The licensee did not identify as proprietary any of the materials provided l
to or reviewed by the inspectors during this inspection.
I 3.
Licensee Action on Previous Enforcement Matters This subject was not addressed in the inspection.
4.
Unresolved Items Unresolved items were not identified during this inspention.
5.
Part 21 Report Follow-up (92716)
(Closed) Item P21/82-01, Plate for Seismic Supports is not ASTM A-36 Material Units 1 and 2.
The licensee provided two nonconformance reports, 82-0/5 and 82-067, issued in reference to the subject material.
In the first instance, the application involved fabrication of lead boxes and in the latter, the material was used for the hydrogen analysis insert panel, located in the Instrument Rack Rooms. In both applications-the tests performed, (wr.lding and mechanical) produced results that showed the material was satisfactory for the application.
l
6.
Testing of Dynamic Piping Supports Unit 1(70370)
,
Periodic testing of snubbers for safety-related, piping to demonstrate operability is required by Technical Specifications (TS), 3/4.7.10.
In i
addition, this section of the TS provides requirements for visual j
inspections, functional testing of hydraulic and mechanical snubbers i
l acceptance criteria, and snubber service life monitoring.
These i
requirements are implemented by Performance Testing (PT) and Mechanical i
Maintenance Procedures (MMP).
The following procedures were reviewed
!
for technical content and compliance with ' applicable TS and regulatory I
requirements.
1-PT-79.3 Rev. 7 Small Bore Hydraulic Snubber F Functional Testing l
MMP-P-HSS-1 2/27/87 Mechanical Maintenance Procedure for Grinnel Removal Functional Testing and Installation i
MMP-C-HSS-6 2/25/86 Mechanical Maintenance Procedure for Removal and i
Installation of the Control Valve Assembly on Milwaukee 10 Inch and
14 Inch Hydraulic Snubbing Cylinders
.
--_ -_
a
__
_ _.-
,
.
q MMP-P-HSS-6 6/30/86 Mechanical Maintenance Procedure for as Found l
Functional Testing of 10 inch and 14 inch Milwaukee Snubber Valve l
Blocks using Wyle API Test Machine.
j Functional testing of small bore snubbers was in progress at the time of l
this inspection.
Discussion with the licensee's representative disclosed that a total of 98 hydraulic snubbers were earmarked for functional testing during this outage. Seventy-six of these were identified as small bore. The inspectors observed the functional testing of the following
hydraulic snubbers.
Mark Number Size System
!
1-SAE-HSS-280 1.5 x 5.00 Main Steam "A" Pressure Control
Exhaust
- 1-SAE-HSS-238 1.5 x 5.00 Main Steam "C" Pressure Control Exhaust 1-SAE-HSS-244 2.5 x 5.00 Main Steam "C" Pressure Control Exhaust 1-SAE-HSS-245 2.5 x 5.00 Main Steam "C" Pressure Control
Exhaust
- Snubber that failed test.
I Test data generated included maximum load achieved, bleed rate, and lockup velocity in compression and tension.
Also the inspectors verified that:
a.
Test equipment was calibrated.
b.
Acceptable instructions and procedures were followed, c.
The force to initiate or maintain motion of the snubber was within the specified range in both directions of travel.
d.
Snubber activa, ion or restraining rate was within the specified range
,
of compression and tension.
j e.
Snubber bleed or release rate was within the specified range of compression and tension.
'
f.
If snubber failed during testing, the cause of snubber failure was being investigated.
g.
The number of units to be tested was in accordance with the TS.
_ _ - - _
Materials and equipment used to conduct the functional tests of the above listed snubbers were as follows:
Equipment:
Wyle Snubber Test Machine, Model 100 S/N 108 Calibration date: 3/9/87 j
ITT Grinnel Shock and Sway Suppressor Tester:
,
'
Model 5434-3 S/N 023 Calibration date: 3/20/87 Test Gauges:
l NQC-1011.2 i
NQC-1011.3 l
NQC-1011.4 l
NQC-1011.5
'
Recorder:
l Linseis, S/N P0672/86 l
Calibration date: 4/23/87 l
Hydraulic Fluid:
GE, Silicone Fluid, SF 1154 P0 NS-030078 Lot Number EJ 828 For these items, the inspectors reviewed quality records to verify completeness, accuracy and compliance with applicable standards, At the close of this inspection effort, May 7, 1987, the ' licensee provided the inspector with the following test completion status.
Total Tested Failure Under Evaluation
,
i Small Bore
4
.
l Large Bore
0
The licensee representative disclosed the following information concerning
,
the reduction of safety-related snubbers in Unit 1:
Design Change 84-71, Pressurizer Safety and Relief Valve Discharge Pipe Support Modifications / North Anna 1, Seventeen hydraulic snubbers deleted from functional testing - no longer safety related, Design Change 86-16, Small Bore Snubber Elimination Sixty-one small bore snubbers removed per reanalysis performed to remove unnecessary snubbers,
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _. _ _ _
- - _ - ____
.
.
!
As a follow-up on work performed under Design Change Package (DCP) 86-16, the inspectors reviewed selected work packages and observed completed field work on six newly installed rigid supports on two 3 inch Main Steam I
(MS) bypass pipe lines located in the MS valve house. The-rigid supports and associated pipe lines were as follows:
Rigid Support Pipe Line No.
Drawing No.
,
SHP-R-305 3"-SHP-531-601-Q2 SHP-R-306 3"-SHP-532-601-Q2 SHP-R-307 3"-SHP-533-601-Q2
!HP-1E Rev. 17 SHP-R-119 3"-SHP-531-601-Q2
,
SHP-R-120 3"-SHP-532-601-02
!
.
SHP-R-121 3"-SHP-533-601-Q2 SHP-1E Rev. 17
'
l The pipe lines were idantified as Class (Q)-2 and were erected in j
accordance with ANSI B31.7 Nuclear Power Piping Code, j
As a result of this work effort, during June 4, 1987, the inspectors noted the following:
a.
Quality Control Activity Report (QCAR) AR-N-87-256, dated 5-13-87 showed that each of the above supports, SHP-R-305, -306 and -307 had
{
been found unsatisfactory in that a gouge appr'ximately 1/64 inches (
o deep and 3/4 inches to 1.00 inch long had been. observed on each of l
l l
the pipes near one of the fillet welds used to attach the hanger j
l attachments (saddles) to the pipe.
The disposition stated that calculations showed that loss of material to erosion corrosion and to the grinding incident was not sufficient to impact minimum wall
'
thickness of this pipe which was 0.300 inch thick.
The conclusion was that the gouges as described in the subject QCAR were acceptable in the as is condition.
b.
As a result of document reviews and discussions on this subject, l
the inspectors ascertained on June 4, 1987, that the fabrication records / weld travelers issued to document weld fabrication on the aforementioned rigid supports were inappropriate, in that they were intended to document welding on structural steel, e.g. hangers.
In this case, the field welds under review, were used to attach hanger components (saddles), four per pipe, on Class E, ANSI B31.7 code piping.
Accordingly documentation of consumables, material traceability and QC inspection (s) are more formalized and more detailed. The discrepancy was identified by the licensee when site engineering and construction requested a baseline examination from the NDE Department, who also noted that because the welds had been painted, it would not be possible to perform an adequate surface examination. The inspectors, inspected the aforementioned welds on June 5, 1987, following paint removal.
Because fabrication of the pipe attachments was erroneously regarded as structural, certain requirements of ANSI B31.7 Code were violated.
These included, but-l
___- _ - -
-
-
_ _ -
.
l H
not limited to positive identification.and traceability of all l
consumables, materials, pipe components etc. as described in Division j
2-727 of the aforementioned code.
The licensee's lack of code required documentation / records in this. regard indicates an apparent violation to 10 CFR 50 Appendix B, Criterion XVII, QA Records.
This
,
I l
apparent violation was discussed with the resident inspectors, and Regional personnel who agreed that since all the requirements specified in 10 CFR Part 2, Appendix C, Section V, were satisfied,
.
,
this matter was not identified as a violation, c.
While inspecting the field welds of hanger SHP-R-305, the inspector l
noted a ' circular indication with a major diameter. of about 3/8 j
inches. The indication was located on the pipe near the second weld
on the left hand side of the bottom saddle, or at the seven o' clock j
position, in the direction of the north wall.
The indication was
pointed out to the licensee representative in charge of welding in j
this area.
Also, this indication was discussed during the exit
interview on June 5, 1987, with the licensee, and stated that it had the appearance of weld metal deposit which had been subsequently i
ground / blended to match the contour of the pipe.
The inspectors requested the licensee to investigate the indication in order - to l
establish its nature and if possible its origin. This item is being identified as an Inspector Follow-up Item (IFI) until the findings of the investigation can be reviewed.
IFI 338-87-12-02 Apparent Base-Metal Indication, Hanger Weld Number SHP-R-305.
d.
In reference to DC-84-71, the inspectors expressed a concern over the
!
net reduction in the number of supports required for the pressurizer j
safety and relief valve discharge.
Therefore, this matter was
<
investigated to assure that the water slug transient had been l
properly accounted for.
A discussion with the licensee determined q
that the problem was being resolved in a three phase process.
Phase 1 includes the installation of metal reflective thermal i
insulation boxes, designed to maintain an elevated water temperature i
(> 400 F), and the up grading of numerous existing supports by the installation of larger snubbers. These actions reduce the water slug transient, resulting in lower pipe stresses and lower support stresses.
Phase 2 includes the partial installation of new supports.
i These supports will be installed, except for their actual attachment to the pipe. These supports are not functional and do not impact the existing piping or support configuration.
Phase 3 includes the
!
completion of the Phase 2 partial installation, such that those
{
supports become functional and the removal of the supports not j
required by the new support system.
This' new support configuration i
requires a new computer piping model. The stresses generated by the
]
new model were reviewed and. found to be acceptable for'both the piping and the supports.
The three phase effort will resolve the water slug transient issue and is to be completed during the next outage (in late 1988).
'I
- _ _ _ - _ _ _ _ _ _ _ _.
__
-_
_-_
.
i
-,
A walkdwon of the area found that holes for anchor bolts have already been installed in preparation for installation the new supports.
All evidence indicates that the licensee has developed and is implementing an acceptable corrective action to resolve the water slug transient issue.
The only follow up required is to check the new support configura-tion, to assure proper installation, after the next outage.
Except for this item discussed in paragraph b. above, no violations or deviations were ideentified.
l 7.
Welding Inside Containment (Unit 1) (55050)
On May 19 and 20, 1987, the inspectors performed a walk through inspection
.:
inside containment to observe various activities in progress including, cleanliness, housekeeping maintenance and work on design change packages.
With regards to this effort, the inspectors noted the following:
a.
In reference to DCP 84-71, discussed earlier in this report, the i
!
inspectors observed material for the fabrication of pipe supports, stored in designated / restricted area. The inspectors identified the
,
following materials and noted same for subsequent review of quality
records.
The materials observed included the following. items:
I Item Purchase Order No.
Hanger No.
10 inch schedule 40 IP 58114 N-900 trunion Ht. No. 84032 N-904 Type A 376 6 inch x 6 inch x 1/2 inch IP 40005 N-904 tube steel Ht/ Lot No.
WO4673 Type A 500Gr.B 6 inch x 4 inch x 1/2 inch MPP-42015 N-36 tube steel Ht No. 227391 A 500Gr.B For these items, quality records reviewed included receipt inspections, purchase orders, vendor inspection reports and, material certifications as applicable.
b.
Discussions with the licensee's representative disclosed that internal leakage has been a continuous problem with 3/4 inch T58 Rockwell Globe valves.
Because repeated attempts to correct the problem have failed, the licensee has decided to' replace them with 3/4 inch Conval Champseal globe valves.
This work was being performed under Engineering Work Request (EWR), No.87-365. During l
- _ _ _ _ _ - _ _ _ _ _ _ _ _
-_
- -
_
.
.
.
l l
a
,
this wal kdown the inspectors noted that three' of the valves identified as 1-SI-189, 1-SI-271 and 1-SI-272, along with a
,
substantial amount of unused 308L, 3/32 inch stainless steel filler i
metal wire Ht No. C53271 had been left near the work area unattended, j
The valves were to be used on drain valves in the safety injection system, line numbers 2 SI-51-1502-Q1, 2 SI-53-1502-Q1 and 2 SI-55-1502 in'the basement of the reactor building.
These items.
were observed near the end.of the day shift on May 19 and again at the start of the day shift on May 20,.1987.
This failure to maintain control' over Safety-Related (SR) materials was an apparent violation of the licensee's Administrative Procedures ADM-8.0 dated August 21, 1986, and ADM-9.6 dated December 14, 1974, respectively.
In the case of the valves, paragraph 5.4.3 of ADM-8 requires SR material to be stored in a ' designated " Safety-Related field Storage Area," whereas for the filler metal, paragraph 4.3 of ADM-9.6 -
requires that all unused bare welding rods... must be returned to
<
the welding foreman.
. upon completion of the job or shift.
This
.
faiiure to comply with procedural requirements is in violation of 10 CFR 50, Appendix B, Criterion V and is identified as violation 50-338/87-12-01 Failure to Maintain Control of Safety-Related Materials.
c.
At the time of this inspection, the licensee was going forward with the modification of the recirculation spray heat exchangers under EWR No.87-166. This modification was being done because the original design did not consider extern'.1 pressurization of the diaphragm seal i
plate without the presence of an internal pressure to balance the resulting forces.
Recent a'nalyses indicate that the desip could undergo only a limited number of overpressurization cycles (such as those experienced during Type A testing of design basis accident j
(DBA) conditions before exceeding the fatigue life of the diaphragm
]
plate.
\\
The modification recommended by Stone and Webster Engineering Corporation, who performed the analyses, called for installing a new, one inch thick diaphragm plate made from type 316L stainless steal, designed to withstand full external pressure prior to performing the i
next Type A integrated containment leakage, test.
The above
.l information was provided by the licensee.on February 20, 1987, as part of a 10 CFR 21 notification.
The modification plan called for i
removing the existing 1/8 inch thick stae.l o s steel diaphragm plate, capping the upper lap-ring faces with type 316L weld metal, in order to minimize the potential for stre a and/or crevice corrosion cracking in this location.
After machining the weld build-up to facilitate proper fitups, the new one inch thick ' diaphragm plates
'
are welded in place to complete the modification. The inspectors reviewed EWR No.87-166 for content and observed the machining operation on the upper end of A and B heat e.xchangers.
Also the
<
i
.
- _ _ _ _ _
i
'
.
.
inspectors observed the buttering / overlay weld on the. upper lag-ring
face of C heat exchanger.
Quality records for the following items
were reviewed for compliance with applicable codes and standards:
'
Item Heat / Lot No.
Purchase Order Diaphragm Plate 22700 ET41826 S/N No. PXE 005 Filler Metal
E 316-L 3/32 inch dia.
64186
'
1/8 inch dia.
64531 ER 316L i
3/32 inch C5483T316L
!
1/8 inch D5483T316L Except for the violation cited above, there were no violations or deviations identified.
8.
Inservice Inspection - Observation of Work and Work Activities (Unit 1)
.]
(73753)
The inspectors observed the ISI activities described below to determine whether these activities were being performed in accordance with regulatory requirements and licensee procedures. The applicable code was ASME Section XI (74S75),
a.
Personnel qualification records for one Level II, one Level I, and a U/T Level I trainee were reviewed, b.
The inspectors observed the in process U/T inspection of the following weld:
FW-1,-2, -3 6" schedule 160 Dwg. #VRA-1-4307 0
& 45 scans The inspection was compared with results of previous examinations and applicable procedure (ISI 205, Rev. 2, AMD 3), in the following areas:
(1)
Availability of and compliance with approved NDE procedures (2)
Use of knowledgeable NDE personnel (3)
Use of NDE personnel. qualified to the proper level (4)
Recording of inspection results (5)
Type of apparatus used (6)
Extent of coverage of weldment (7)
Calibration requirements (8)
Search units (9)
Beam angles (10)
DAC curves
_ _ _ _ _ _ _ _ _ _ _
________ _
_
J
.
.
1
)
(11)
Reference level for monitoring discontinuities j
(12)
Method of demonstrating penetration j
(13)
Limits for evaluating and recording indications
(14)
Recording significant indications (15)
Acceptance limits l
Within the areas inspected, no violations or deviations were identified.
l 9.
Inservice Inspection
. Data Review and Evaluation (73755B) (Unit 1)
f a.
Eddy Current Inspection Steam Generator Tubes.
Results of the eddy current inspection were discussed with cognizant licensee engineers. The inspector was advised that the examination j
~
was expanded to include 100% of the tubes in each of the three steam j
generators (S/Gs) with the following results:
Previously Plugged Currently Current.
Plugged This Outage Plugged
% Plugged A
126
209-6.17 I
l B
116
178 5.25 C
153 118 271 7.99 l
!
Two tubes were pulled from S/G "A" by Westinghouse. These tubes will be examined to determine the cause for _ pronounced ID cracking g
identified by eddy current in this steam generator. Results of this
.
examination will be reviewed as they become available.
l Following the May 18-22 inspection, the inspectors were invited to attend a meeting called by NRR to discuss with W and VEPCO, the.possible cause for the ID cracking of SG tubes.
}[ indicated that they had no good explanation for this phenomenon at this time..Because of thi s. situation W recommended and VEPC0 agreed to plug all tubes with distorted i
indications and thereby avoid possible questions that could delay returning the plant to power. )! expressed hope that by applying a stress relief treatment to vulnerable SG tubes and exercising tight control on the primary water chemistry they may extend the services of the SGS to design life. At the same time W indicated that they have started preliminary engineering studies on SG replacement for North Anna.
Within the areas inspected no violations or deviations were identified, i
i
%_
_ _ _ _ _. _ _ _ _ __ _ _ _ _. _ _ _ _ _ _ _
l
.
I 11'
!
i J
10.
Review of Nondestructive Examination Records and Evaluation of Results i
(57060, 57070 and 57090), (Unit 1)
i
.
Records of surface and volumetric (radiography) examinations. performed i
during this outage were selected for review to verify compliance with I
applicable code, procedure and regulatory requirements. These tests were I
performed on welds involved in Design Change Packages and/or. repairs:
l Item Line No.
Drawing
!
3 inch long nipple 3/4 inch-CH-A19-602-Q1 730362 3 inch long nipple 3/4 inch-CH-A20-602-Q1 730362 W-9B (end prep)
1 inch-SS-221-601-Q3 SS1221AB7 q
W-10B (end prep)
I inch-SS-221-601-Q3 SS1221AB7 q
38A (end prep)
3/4 inch-DG-95-602-Q3 1021A Rev. 7
{
<
Magnetic Particle
'
.l W-8 and -9 18 inch-S2E-1-301 M-100-Rev. 1 W-2 10 inch-WHPD-1-301C E87286-1-M-104 Rev. 0
Radiograph W-3X and -4X'
2 inch / x.154 inch CH-6-6021-Q1 l
The above radiographs were reviewed to verify the following attributes:
I J
Penetrometer type, size, placement l
Penetrometer sensitivity
'
Film Density, density variation Film identification Film quality
Weld coverage (overlap).
,
i In addition, the inspectors reviewed personnel qualification records and
certification of materials.
Within the areas inspected no violations or deviations were identified.
,
Incore Flux Detector Thimble Tube Leakage Unit 1 (62702)
11.
l l
On April 28, 1987, the licensee informed the resident inspector that Eddy i
'
Current (EC) testing of the Unit 1 incore detector thimbles revealed wall
.'
degradation resulting from fretting action between the lower core plate and the fuel assembly guide tube. Twenty-three of the 50 thimbles (0.495" nominal wall thickness) exhibited wall thinning ranging from 10% to 49%.
,
,
Westinghouse removed the tube showing 49% degradation for examination..
l
'
'
i
- - _ _ - - - _ _ __.
..
_ _ _ __ _
<
.
i
'
North Anna's Station Manager heard about this' condition during a meeting with PWR plant managers. He then discussed the matter with W and made
'
arrangements for the EC examination to be performed during this outage.
The licensee believes.that wall thinning (fretting) resulted from vibration caused by primary coolant turbulence in the area.
Discussions with the licensee's cognizant engineer disclosed that the EC examination was conducted using the MIZ-12 system with an absolute probe. measuring 0.185" diameter and multifrequency technique. In that this procedure was identified by W as proprietary the inspectors did not review the procedure.
The inspectors ascertained that the thimble tub og was made of type 316 stainless steel tubing, 0.300 "outside diameter and 0.050" wall thickness,.
l Section 7.7.1.9.2 of the North Anna UFSAR provides a detail explanation of the detector drive system and discusses the consequences of small and i
l large leaks resulting from cracking and or pipe rupture in this system. A l
Loss of Coolant Accident (LOCA), resulting from a rupture / break through a
I 3/8 inch diameter hole has been analyzed and is discussed in Section 15.3.1.1 of the UFSAR.
Within the areas inspected no violations or' deviations were identified.
12.
Secondary Side Ultrasonic Examination Unit 'l 962702 Because of the pipe break incident at Surry, the licensee decided to perform thici. ness measurements on suspect locations of the steam
,
extraction and feedwater systems.
To assist in the selection of these areas, the licensee retained the services of Technicon Enterprises, Inc.
(TEI).
Discussions with the licensee's cognizant engineer and TEI's representative, disclosed that selection of pipe locations was based on work reported in EPRI Report No. NP-3944 and the Surry experience.
Measurements were taken with an ultrasonic digital measuring device l
I attached to a Nova mini-logger. The controlling procedure for this work effort was ISI-ADM-8.0, Secondary Single Phase Piping Examinations.
Before taking any measurements, the area was laid out in a grid pattern.
l The readings were taken in a predetermined sequential manner.
This I
allowed the engineers to review the erosion pattern in a more accurate
and expeditious manner.
fipe section components which failed to meet l
calculated minimum wall which was based on projected weLr life, were I
either replaced during this outage or scheduled for reinspection or replacement on subsequent outages.
...
_ _ _ _
)
i
-
-
i
I The systems examined included those designated as single. phase- (steam only) and two phase (steam and condensate).
The systems and the total number of areas / components within a system designated for examination were i
as follows:
)
SINGLE PHASE PIPING TWO PHASE PIPING System Total Components System Total Components To Inspect To' Inspect
-
'
Condensate
Extraction
(WCPD & WFPR)
Steam (S1E, S2E i
S3E &'S4E)
.
Flash EVAP Recire.
)
(WFPD, WHPD, (WER)
W1D & W2D)
L. P. Drains
Steam Gen Blowdown
,
(W3D,W40, (WGCB)
WSD & W6D)
MSR Drains
H. P. Vents
(WRRD, WRD & WSD)
(S2V & S3V)
,
Total 85 Totals 47 Discussions with the licensee's cognizant engineer, on June 18, 1987, r evealed that because of these examinations they would be replacing pipe sections in 17 locations within the feedwater system, five in the extraction steam system and one in the main steam release drain system.
i Also because of the findings, an additional 70 locations / samples were I
added to the original population.
The inspectors observed welding l
in progress on a 18 inch, end-cap to a feedwater header on line l
No. 26-WFPD-6-901 weld number, FW-1.
The governing code was USAS B31.1, I
Power Piping.
The inspectors observed the welding and reviewed quality j
records including procedure and welder qualifications; filler metal
^
certifications and fabrication records to verify compliance with i
applicable code requirements.
~
l Within the areas examined, no violations.or deviations were identified.
'
i I
i i
!
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _. _ _ _ _. _ _ _. _
_ _ _. _
_ _. _ _ _. _
-...___..J