IR 05000498/1987044

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Insp Repts 50-498/87-44 & 50-499/87-44 on 870622-0710.No Violations or Deviations Noted.Major Areas Inspected:Actions Re Findings Identified in Previous Insp Repts & Incident Review Committees 301 & 364 & IE Info Notice 86-029
ML20237K494
Person / Time
Site: South Texas  STP Nuclear Operating Company icon.png
Issue date: 08/11/1987
From: Garrison D, Ireland R, Norman D
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
To:
Shared Package
ML20237K482 List:
References
50-498-87-44, 50-499-87-44, IEB-85-003, IEB-85-3, IEIN-86-029, IEIN-86-29, NUDOCS 8708190283
Download: ML20237K494 (10)


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'l APPENDIX

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, U.S. NUCLEAR REGULATORY COMMISSION- .J

REGION IV

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l hRC Inspection Report: 50-498/87-44 1 Construction Permits: CPPR-128 i- 50-499/87-44 CPPR-129 I- Dockets: 50-498 l 50-499 i

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L Licensee: ' Houston Lighting & Power Company (HL&P)' l P. O. Box 1700  !

Houston, Texas 77001 l

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Facility Name: SouthTexasProject, Unit'1:(STP). .j Inspection At: ~ Bay City,. Texas i Inspection Conducted: June 22, 1987 through July 10, 1987 Inspectors: [c@ho E.' Norman,. Reactor Inspector, Engineering 7/5d/g/

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.Section, Reactor Safety Branch ( /

T). L. Garryton, Resident Inspector, Project

/b/Y D6th Section.t, Reactor Projects Branch Approved: M C\ /,r//

R. 'E. Ireland, ' Chief, Engineering - Section 7/30/#7 Date '

Reactor Safety Branch 9 Inspection Summary Inspection' Conducted June 22, 1987, through July - 10,'1987 (Report 50-498/87-44)

Areas Inspected: Routine, announced inspection of actions relative to findirgs identified in NRC Inspection Reports 50-498/87-21 and 50-498/87-36, review of actions in regard to Incident Review Committees 301 and 364, Part 21 Nos. 87-16 and 87-29, and IE Information Notice 86-2 Results: Within the areas inspected, no violations or deviations were  !

identifie B70814 DR ADOCK 050 4]O

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Inspection Conducted June 22, 1987 through July 10, 1987 (Report 50-499/87-44)

Areas Inspected: No inspection of Unit 2 was conducte Results: Not applicabl .

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f 1. Persons Contacted HL&P G. E. Tandy, Lead EQ Engineer W. P. Evans, Project Compliance Engineer C.-A. Ayala, Lead Licensing Enginee R. A. Hernandez, Project QA Analysis S. M. Head, Lead Licensing Engineer .

S. D. Phillips, Project Compliance Engineer Bechtel R.' M. Ulanday, EQ Engineer R. A. Witthauer, EQ Engineering Group Supervisor Inspection Summary .(Closed) Open Item 498/8721-01 This item was originally documented because of a concern that gate valves, whose closure was controlled by a limit switch (NSSS Valves)

rather than a torque switch, could have leakage between the seat and gat Additional review during this inspection showed that the valves were actually seated by a thrust developed by the operator and applied

~through a compensating spring pack located on the valve stem. The closirig thrust was adjusted by setting a predetermined deflection of the spring pack with the valve stem nut. The limit switch was set to trip at the position of the gate corresponding to spring pack preload. STP has chosen to maintain wiring uniformity between all !

operators; therefore, a torque switch wired in parallel with the ;

limit switch was set for its minimum value and will not control the J'

valve closure. A desirable feature of limit switch controlled valves is that the closing thrust is limited by the spring pack preloa In the event deposits on the valve seat or other obstructions should prevent a limit switch trip, trip or burnout could occur. This is l unlikely, however, since the plant operator would be made aware of this condition by the valve position indicator lights and other alarms if the. valve did not properly seat. This item is close (Closed) Open Item 498/8721-02 i

Inspection procedures for Limitorque valve operators require verification that right hand thread worm bearing locknuts for SMB

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operators and ACME stem locknuts on operators have been stake There was no requirement to check the nuts for tightness prior to l stakin !

l During this inspection, it was found that the applicant had reviewed l data to determine that no SMB operators at STP had right hand threads and the precedure was not applicable. It was also determined, during

,.- operational testing of valves, that there was no indication of loose ACME stem nut Procedures were also revised to require checking

, tightness of the nuts prior to staking in the futur This item is close ' (Closed) Unrecolved Item 498/8721-03

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During the previous inspection of Limitorque operators, it was found l k that the applicant's procedures required two T-drains at the low

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point of all valve operator motors. It was also observed during the

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NRC walkdown inspection that T-drains were not at the low point on several motors and other motors did not have the required number of l

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T-drain l

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As a result of the above findings, the applicant took the following actions: l

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(1) Initiated communication with Limitorque (telephone conversation of April 21, 1987, and confirmatory letter of April 21,1987)

which resulted in a letter from Limitorque dated April 22, 1987, which stated with respect to T-drains that "AC containment motors should include two TEE drains at the lowest point of the motor and DC safety-related actuators should contain one TEE drain at the lowest point of the motor."

.( 2 ) Initiated communications with Limitorque (telephone conversation of May 5,1987, and a later conversation for which documentation is not available) which resulted in correspondence from Limitorque dated May 15, 1987 and May 19, 1987, stating with respect to T-drains that "T-drains should be installed at the lowest available location" (letter dated May 15,1987);and i

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"The maximum angular displacement that T-drain may be displaced i from lowest point of motor is 45 " (letter dated May 19,1987).

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(3) Issued a specification change notice (SCN) to clarify drain fitting requirements for class IE valve operator motors. The l change required: l (a) AC motors in harsh environment are to have two T-drains at the lowest motor drain plug *

(b) DC motors in harsh environment are to have one T-drain at the lowest motor drain plu .. .

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.5 The applicant subsequently reinspected all drain plugs and repositioned plugs which were located such that water accumulator l inside'the motor could come in contact with motor windings. This

rework ~was witnessed by the NRC inspector and this item is closed. (Closed) Open Item 498/8721-04 l During a previous NRC walkdown inspection of Limitorque velve operators, it was observed that shipping caps were installed on the gear box relief valve of most operators which had already been turned over to operation During this inspection, it was observed that startup work requests (SWR) had been initiated and removal of the caps had been accomplished. This item is close (Closed) Open Item 498/8721-05 Valve operator SI-1813 was found to have either pitted or dirty limit switch contacts, and limit switch gear grease had been leaking into the limit switch housing. The . operator was considered operable, but could have failed earl SWR 16014, which required the switch to be replaced, was completed on

'May 18, 1987. Since this was considered an isolated incident, no further corrective action was required and this item is closed, (Closed) Violation 498/8721-06 Several Limitorque valve operators, which hgd dual voltage motors, had motor leads spliced with blind barrel crimp splice Documentation used to substantiate qualification of the operators made no mention of the splices, nor had the splices been tested and qualified separate from the operator As a result, the applicant inspected all Limitorque valve operators with dual voltage motors and.found that all 23 had the blind barrel crimp splices in motor leads. The splices were then removed and replaced with in-line splices which were insulated with Raychem WCSF-070 shrink tubing. This work was witnessed by an NRC inspector and found to be acceptabl This item is closed, y (Closed) Unresolved Item 498/8721-07 During the NRC walkdown inspection, the limit switch material in -

CV 8377A and both the limit and torque switches in CV-25 were .'

identified as Durez which has not been qualified for use in harsh environments. The applicant stated that the operators were not required to be qualified since they porformed no essential safe i shutdown nor postaccident function. Additional clarification of this item was required of the applican ,

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'6 During the followup of the above item, documentation was reviewed which showed that the CVCS valves were not essential for a safe shutdown during an accident occurring in the room where the valves are located. They are required to mitigate an accident at other locations, but are not required to operate in an accident environment; therefore, they are not required to be qualified for a harsh environment. This iten is close (Closed) Unresolved Item 498/8736-01 It was found during the inspection, that' splices which did not comply with Raychem configurations had been qualified by testing configurations to envelope those at STP, with one or two attributes which were different from the configuration qualified by Raychem. If a combination of the attributes were included in a single splice, an unqualified splice could exist; therefore, the applicant was to perform a records review to determine whether unqualified splices did exist at ST During this followup, it was determined that 14 cable terminations contained more than 1 attribute which was different from the Raychem configuration. In e y h instance, the splices were determined to be in a non-accident location and were determined to be acceptable for use. This item is close j (Closed) Unresolved Item 498/8736-02 l Splices qualified by Report 17859-02P were supported for a 40-year life in a 120*F environment. Several areas outside containment were at 135 F and there were no restrictions on using the splices in those areas. A calculation was subsequently performed by the applicant at 135 F and it was found that qualification of the splices could not be supported in certain rooms. It was not known at the time 'of the inspection if splices qualified by Report 17859-02P were used in any of those area As a result of the NRC findings, the applicant conducted a review of the applicable rooms with the following results:

MAB 037 - no Class IE connections

MAB 054 - no Class IE connections

MAB 0244A - T - no Class IE connections  ;

MAB 039 - Certain splices had bend ratios and hold outs which were not qualified by the Raychem qualification test Also, as stated above, their qualification could not be supported by Report 17859-02P. The applicant did, however, find that Test Reports 17859-02B and 7859-02B _ _ _ _ _ _ _ - .

. , , . . supported qualifica ;on of the splices. These reports will be included in the qualification documentation for '

the splice MAB 041 - This room is not' subject to a design basis accident; therefore, splices in the room do not require qualificatio Based on'the additional documentation provided to support qualification, this item is close ; j. (Closed) Open Item 498/8736-03 During the walkdown inspection of Raychem splices resorted in NRC ,

Inspection Report 50-498/87-36, two discrepancies, w11ch were l considered to be isolated incidents, were identified by the NR During thi.s followup inspection, it was verified that the discrepancies had been properly dispositioned and repaired as documented in NCRs SE06367 and SE06368. This item is close k. IE Information Notice (IEN) 86-29 (Closed)

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IEN 86-29, " Effects of Changing Valve Motor Operator SwitchL Settings," was provided as an alert that setting torque bypass switches to meet requirements of IE Bulletin (IEB) 85-03 could affect valve position indication and signals such as "permissives". to other equipment. The problem occurs when th'e torque bypass switch and valve position indicators share the same limit switch roto Therefore, when the position of the rotor is changed to extend the range of the torque bypass switch, the closed position indication is .

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also change Documentation was reviewed during this inspection which showed a review of all valves by the applicant. It was determined from the

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review that all limit switches have four rotors and that the torque j bypass switch is on a rotor separate from the indicator lights and 1 signals to other equipment. This item is close I 1. Part 21 (87-29) ' Closed)

A problem was reported at Davis-Besse Nuclear Power Station, Unit 1, concerning inadequate thrust to close certain isolation valves against the design differential pressure. The low closing thrust was determined to be a result of the valve ' *s having an unbalanced torque switch. The concern of the Part t n art is that Limitorque 1 did not supply adequate instructions h w e torque switch )

balance, and setting of an unbalanced to the recommended setting could result in a torque switch grior to operation of the. valve. This problem had been discoveied while setting valves to the requirement of IEB 85-0 _---_ - _-

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The NRC followup inspection to the applicant's program for' setting, and maintenance of the setting, to ensure proper valve operation for IEB 85-03 valves and all remaining safety-related valves was reported L'

in NRC Inspection Report 50-498/87-21. It was found that during

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reinspection and rework of Limitorque valve operators to CIP 2.2-62 that_ torque switches were removed, reinspected, cleaned, and -

reinstalled (or replaced with a new switch) with precautions concerning unbalance. The torque switches were subsequently set at a predetermined setting, corresponding to a desired thrust levol, and tested under static and flow conditions with acceptable result This item is close m. Part 21 (87-16) (Closed)

Limitorque reported the failure of a valve operator at the Trojan Nuclear Plant as the result of motor lead wire insulation damage. A

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lead wire insulation change was made on DC motors manufactured by Peerless-Winsmith', with Limitorque approval; this affects motors manufactured during the December 1984 through December 1985 time period. The problem has been considered as maintenance related because of the lead wire 3 stiffness, and Limitorque is in the process of qualifying, by testing, a sleeving system applied over the existing lead wir As a result of Limitorque's notification, the applicant reviewed records for all Limitorque operators and found that the Part 21 was applicable to the following operators:

DIAFMOV-0019 DIAFM0V-0143 DIAFM0V-7526

A megger test was conducted on the operators and DIAFMOV-0143 failed i the tes an identicalNCR motor.SE-05724 Changewas written, Approval and Report Request the motor was (CARR rep)

1667 laced with was a 3 proved to add qualified Raychem sleeves over the motor leads of the t1ree operators until a final disposition of the problem is made by ;

Limitorque. A field change request (FCR) was issued to accomplish the work approved by the CARR. The completed work was verified by an NRC

. inspector and determined to be satisfactor This item is closed, n. IRC-301 (Closed)

This item was initially reported by a telep'none call to the NRC on November 19, 1985.- An interim report was made to the NRC.on December 1~6, 1985, in which it was reported that various deficiencies had been identified concerning Limitorque valve operators. As a result of the deficiencies, an inspection program was initiated by STP to review all safety-related valve operators for conditions identified in the interim report.

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n' 9 l l_ .A review'of the applicant's a:tions in response .t, the identified findings, and other items concerning Limitorque vahe operatur ,

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qualification, was made by the NRC and reported in'NRC Inspection Report 50-498/87-21. Several findings were identified in the repart relatEd to valve operator qualif3 cation. Resolution of.those items '

was. reviewed during-this inspection and resuits of the review are l reported in paragraphs 2.c, 2.d, 2.e, 2.f, and 2 9 of this inspectico i

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report. .All issues of IRC-301 and those identified during the NRC

! inspection have been resolved. This item is closed.

L1 IRC-364 (Closed)

This item was reported'to the NRC by telephone on February 19.-198 The first. interim report was made to the-NRC on March.18, 1987.' This report was made as a; result of d finding by the NRC staff that Raychem insulation on cable-to-cable splices in cor.tainment penetrations had not been installed according to Raychem '

instructions. Their qnlification was, therefore, questionable. As a result of there findings, an inspection nrogram was inf.tiated by the applicant to inspect all containment penetration splicer for proper installation of Raychem insulatio The NRC inspector. reviewed the apM.icant's actions in regard to resolution of the findings and the program to prevent recurrenc Details of that inspection are reported in NRC Inspection Report 50-498/87-36. Several findlngs were identified in that report, and reselution of the findings aas reviewed 6: ring this ins,nection-and dircussed in this report. All issues 6f IRC-364 and those identified during the NRC inspection have been resolved. This item is close SSER3,8.1-RaychemSplices(Close_d},

During the staff electrical inspection, it was discovered that a-number of Raychem sp'tices in the containment penetrations did not comply with Raychem reconnendation Supplement 3 to the SER required that the appliccnt perfDrm a 100 percent inspection of penetration splices located inside and outside the containment. It was further required thst all splices which did not. comply with i Raychem installation instructions be reworked. . That provision has been modified to preclude the need for rewerk of those splices which do not comply with Raychem recommendations providing the splice configurations in question have been tested and qualified at environmental . conditions which envelope the STP environmen Splices which did no~t meet the criteria were required to be reworke Results of a Region IV followup inspection of IEN 86+53, " Improper Installation of Heat Shrinkable Tubing," were reported in NRC Inspection keport 50-498/87-36,'and the followup of findings from that report have been addressed in paragraphs 2.h, 2.1,-and 2.j of

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this-report. During this inspection, it was determined that the penetration splice reinspection, and rework effort had been

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i completed and that all installed Raychem splice configuratiotis are f supported by environmental qualification tests. This item is close J 3. Exit Interview I

Since this inspection consisted of followup on previously identified .

findings, and covered no new items, a formal exit interview was not 1 conducted. Personnel identified in paragraph 1 vere kept apprised of the inspectir,n results throughout the inspectio :

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