ML20215J256
| ML20215J256 | |
| Person / Time | |
|---|---|
| Site: | Vogtle  |
| Issue date: | 10/09/1986 |
| From: | Foster D GEORGIA POWER CO. |
| To: | Grace J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| References | |
| REF-PT21-86 GN-1095, IEIN-86-053, IEIN-86-53, NUDOCS 8610240366 | |
| Download: ML20215J256 (6) | |
Text
Georgia Fdwer Company Post Office Box 282 Waynesboro. Georgia 30830 Telephone 404 554-9961, Ext. 3360 404 724-8114. Ext. 3360 k
L
%d,lsL 36 0CT 14 P l l 23 Georgia Power the southem electro system Vogtie Project October 9, 1986 United States Nuclear Regulatory Commission Region II File:
X78G03-M124 Suite 2900 Log:
GN-1095 101 Marietta Street, Northwest Atlanta, Georgia 30323
Reference:
Vogtle Electric Generating Plant-Units 1 and 2; 50-424, 50-425; Raychem Site-Designed Cable Splices; Letter GN-1070 dated September 5, 1986 Attention: Mr. J. Nelson Grace In previous correspondence on this subject, Georgia Power Company described a
potentially reportable concern whereby some Class IE site-designed cable splices in LOCA/HELB areas may have been made, using Raychem heat-shrinkable insulation, to installation criteria for non-accident ~ areas.
I&E Information Notice 86-53 provides notification of conditions of this type discovered at other facilities.
Georgia Power Company has completed its evaluation of this condition and has concluded that it is reportable pursuant to the requirements of 10 CFR 50.55(e). A summary of the evaluation is attached.
This response contains no proprietary information and may be placed in the NRC Public Document Room.
Yours truly,
/-
M D. O. Foster A
REF/DOF/tdm Attachment xc:
U. S. Nuclear Regulatory Commission Document Control Desk Washington, D. C.
20555 J. H. Miller R. A. Thomas L. T. Gucwa J. P. O'Reilly D. R. Altman C. W. Hayes G. F. Head P. R. Bemis G. A. McCarley R. E. Conway J. A. Bailey R. W. McManus J. T. Beckham
- 0. Batum D. S. Read R. H. Pinson G. Bockhold Sr. Resident (NRC)
P. D. Rice C. E. Belflower C. C. Garrett (0PC)
B. M. Guthrie J. F. D'Amico J. E. Joiner (TSLA)
D. E. Dutton E. D. Groover D. Feig (GANE)
I 0610240366 861009 7 "I
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PDR ADOCK 05000424 Ec
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8 EVALUATION OF A POTENTIALLY REPORTABLE CONDITION RAYCHEM SITE-DESIGNED CABLE SPLICES Initial Report: On August 12, 1986, Mr.
C.
W.
- Hayes, Vogtle Project Quality Assurance Manager, informed Mr.
E.
F.
Christnot of the USNRC Region II of a potentially reportable condition concerning the improper installation of some Raychem heat shrink tubing in harsh environments.
Background Information: Heat shrinkable material supplied by Raychem Corporation is used to make Class 1E electrical cable splices at device pigtails (for termination).
It provides electrical and environmental isolation by covering the individual conductor splices and by maintaining an adequate seal between the cable splice and the harih environment.
This material is procured under specification X3AJ118.
To ensure that the appropriate heat shrinkable material is utilized, the supplier provided "use-range" criteria for the various splice configurations.
The~ "use-range" criteria list the maximum and minimum dimensions for each heat shrinkable component which consist of tubes and breakout boots (applied to more than one conductor) to be used for various special splice configurations on the project. The heat shrinkable material varies for splices (of similar dimension and configuration) located in harsh environment and non-harsh environment locations.
These variations are delineated in the "use-range" criteria.
The majority of splices are in-line splices (involving one conductor only) using heat shrinkable material which are covered by standard splice kits furnished by Raychem.
In this type of " splice, the same type of heat shrinkable material is used regardless of the area in which the splice is located.
There are cases, however, where the splice involved more than one conductor.
This type of splice requires a special heat shrinkable material configuration and is identified as a special splice.
The special splice is identified by field construction who determines the specific heat shrinkable material to be applied over it through a field change request (FCR) documen.t.
Project Field Engineering (PFE) then dispositions the TCR by ensuring tht the heat shrinkable construction is acceptable based upon the information in the "use-range" cri teria,
1.e.,
the material selected, is in fact, the correct size and configuration for the splice and for the type of environment in which the splice is located.
As a result of the review of NRC Notice IEN 86-53 and a recent NRC jobsite audit, 5 field change requests (FCRs) generated for special splices were found to have been dispositioned and approved by PFE with incorrect heat shrinkable material sizes.
Engineering review determined that this condition resulted from the misapplication of the "use-range" criteria by both field construction, who generated the FCRs, and by
- PFE, who dispositioned and approved the FCRs.
Specifically, the electrical conductor splice over which the tubing or boot was to be applied was too large for the heat shrinkable material selected to attain an adequate seal in a harsh environment or to provide the required electrical isolation.
Subsequently, a broadness review of all known FCRs of this type (87 total) was made and identified 4 additional FCRs with the same condition.
The condition, as identified in the 9 FCRs, is limited to 24 control and instrumentation splices involving 80 circuits (83 cable ends).
A summary of the list of FCRs and the corresponding circuit ends with improper heat shrinkable material sizes is shown in Table 1.
Engineering Evaluation:
Because the heat shrinkable material is too small for the splice, it may break over a period of time (or sometimes sooner) after it is shrunk over the splice.
This breakage could expose the conductor to the environment causing current leakage to ground or provide a path between the exposed conductor and ground (via the metallic termination box) causing shorts.
These conditions could impact the operation of the safety-related load or device connected to the class 1E cable.
The 80 identified circuits with the described heat shrinkable splice materials were evaluated to determine the impact of the above condition to the safe operation of the plant.
The evaluation revealed that 71 of the circuits are used to supply electric power to solenoids.
Failure of these circuits will deenergize the solenoids and cause them to assume their safe position.
Failure of the remaining 9 circuits due to the misapplication of the heat shrinkable material could impact plant safety as demonstrated by the following:
a.
5 circuits, (18Y1805SA, 1BY1805SB,1BY1B05SC, IBY1805SD, 1BY1805SE) with the-cables identified under E-FCRB-14642, in Table 1,
are used to supply 120 VAC power to the process protection cabinet containing the signal processor and instrument loop power supply for the channel 2 protection instrument and the type A, category 1,
post accident monitoring (PAM). instrumentation.
Failure of the circuits due to the improperly applied heat shrinkable material could cut the power supply to the process protection cabinet.
This condition could prevent the PAM instrumentation from providing the control room operating staff with the primary information needed to reach and maintain a safe shutdown condition after a design basis accident.
b.
The other four circuits which are identified under E-FCRB-16828 (11CQPS1YM, 12CQPS2XU, 13CQPS3XY, and 14CQPS4YC0) are instrument circuits and are associated with the safety injection system for monitoring high containment pressure and are designed to initiate a safety injection signal, main steam line isolation signal, and containment spray actuation signal.
Failure of the heat shrinkable materials could render the circuits ineffective and could result in the loss of the protection system's safety actuation capability and may jeopardize the plant's ability to safe shut down.
1 Evaluation of Quality Assurance Program Breakdown: This condition was the result of the misapplication of one of the many Raychem criteria to these special spliced heat shrinkable tubing materials and the lack of clear understanding of the Raychem supplied information regarding the "use-range" criteria.
Since the misapplication involved only one selection parameter and since the broadness review did not identify any other design deficiencies, this condition does not constitute a significant breakdown in either the Raychem or Bechtel Power Corporation Quality Assurance Program.
==
Conclusion:==
Based on the above evaluation, the plant safety could have been impacted had the condition of the cable splices used in plant safety systems gone uncorrected.
Therefore, Georgia Power Company has concluded that a reportable condition does exist as defined by the reporting criteria of Part 10CFR50.55(e)
A Part 10CFR21 notification is not required since the NRC has been adequately informed of the existence of this condition (see Information Notice 86-53).
Corrective Action: The broadness review gave complete technical analysis for determining the correct application of the Raychem "use-range" criteria as it pertains to electrical conductor splices in harsh environments.
As a result of this information, the following corrective actions are being implemented:
1.
Change' Control Package (CCP) number F10140E is being issued to correct all of the improperly applied heat shrinkable material on the splices listed in Table 1.
This activity is being tracked by MTS #EAl-1296 and the corrective action is scheduled for completion prior to fuel load.
2.
Special vendor training was held at VEGP jobsite for the GPC-Construction and PFE engineers clarifying the implementation of the heat shrink requirements and providing additional information on the "use-range" criteria.
Raychem has also certified the GPC-Construction and PFE engineers who have successfully completed this training.
Raychem special splice applications data has been logged into the project's data files under a new log number AX3AJ118-39.
3.
To prevent recurrence of the condition discussed above in Unit 2, construction specification (X3AR01, Section E9) has been revised (see E-FCRB-18056) to require that special splice designs be verified by certified engineers prior to the normal approval cycle defined in the present project procedure, and to require that the site keep the certified engineers training records on file.
l....
TABLE 1 SPLICES WITH IMPROPERLY DESIGNED RAYCHEM HEAT SHRINK MATERIAL CIRCUIT END FCR NO.
E-FCRB-10867 SOLENOID POWER & CONTROL 1BR888SBl 1BR888SD1 CABLES IBR888SG1 IBR15214SBl E-FCRB-ll212 1BR15214SCl IBR15214SD1 IBR15214SE1 1AR8160SE1 E-FCRB-11941 1AR8160SF1 1AR8160SG1 1AR8160SJ2 LAW 5244SA2 E-FCRB-12204 1AW5244SB2 1AW5244SC2 1AW5244SD2 1AW5245SA2 LAW 5245SB2 1AW5245SC2 1AW5245SD2 1AWOS20SA2 E-FCRB-12513 1AWOS20SD2 1AW0520SE2 1AWOS20SF2 1AWO530SA2 1AWO530SD2 1AWO530SE2 1AWO530SF2 1AW15197ASDL E-FCRB-12694 1AW15197ASE1 1AW15197ASF2 1AW15197ASG1 1AW15198ASD1 1AW15198ASE1 1AW15198ASF2 N/
1AW15198ASG1 E-FCRB-14642 PROCESS PROTECTION CABINET LBYlB05SA2 POWER SUPPLY CABLES 1BYlB05SB2 1BYlB05SD2 LBYlB05SE1 IBYlB05 sal 1BYlB05SBl 1BY1805SC2 N/
1BYlB05SDL 933/CAC
.'.ou e
TABLE 1 (Continued)
SPLICES WITH IMPROPERLY DESIGNED RAYCHEM HEAT SRRINK MATERIAL FCR NO.
CIRCUIT END E-FCRB-16828 PROTECTION INSTRUMENTATION llCQPSlYM2 CABLES 12CQFS2XU2 13CQPS3XY2 sf 14 COPS 4YC2 E-FCRB-ll295 SOLENOID POWER AND CONTROL 1AR8047SE2 CABLES 1AR8047SF2 1AR8047SG2 1AR8047SH2 1AR8871SD1 1AR8871SG1 1AR8871SJ1 1AR8871SKl 1BR8825SCl 1BR8825SD1 IBR8825SE1 1BR8825SF1 1BR8890ASD1 1BR8S90ASCl 1BR8890ASE1 IBR8890ASF2 1BR8890BSCl 1BR8890BSD1 1
1BR8890BSE1 1BR8890BSF2 1BR8843SCl 1BR8843SD1 IBR8843SE1 1BR8843SF2 1BR8824SCl l
1BR8824SD1 l
1BR8824SE1 i
1BR8824SF2 1BR8881SCl 1BR8881SD1 IBR8881SE1 1BR8881SF2 1BR8823SCl 1BR8823SDL 1BR8823SE1
\\[
IBR8823SF2 933/CAC