IR 05000327/1987028
ML20214U352 | |
Person / Time | |
---|---|
Site: | Sequoyah ![]() |
Issue date: | 05/21/1987 |
From: | Jape F, Lehanan J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
To: | |
Shared Package | |
ML20214U325 | List: |
References | |
50-327-87-28, 50-328-87-28, NUDOCS 8706110152 | |
Download: ML20214U352 (5) | |
Text
. _ _ - _ - -
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ - _ _ _ _.
-
._
_._ _. - - - - _ - - _ _ _ _ _ - - _. _ _ _ ___-_-___ - __- - -_ - _
'
'
-
..
[>R Mc,Io o
UNITED STATES NUCLEAR REGULATORY COMMISSION
[*
'
- "
REGION il n
_ g
,, j 101 MARIETTA STREET,N.W.
- ATLANTA, GEORGI A 30323
~...
Report Nos.:
50-327/87-28 and 50-328/87-28 Licensee: Tennessee Valley Authority 6N 38A Lookout Place 1101 Market Street Chattanooga, TN 37402-2801 Docket Nos.:
50-327 and 50-328 License Nos.: DPR-77 and DPR-79 Facility Name:
Sequoyah 1 and 2 Inspection Conducted: May4-6,198J f/b[J')
Inspector:
A c-
~/
Date Signed J. J. Lenahan (
Tb Approved by:
..
. /WL
' f(64fl_.
F. Jape, Sectio'n Chief f/
Date Signed Enginerring Branch Division of Reactor Safety SUMMARY Scope:
This routine, announced inspection was conducted in the areas of followup on licensee action on previous inspection findings and a licensee identified item (LER).
'
Results: One violation was identified - Hanger Design Loads Exceeded Snubber Capacity, Paragraph 3.b.
+
$
i 8706110152 870604 PDR ADOCK 05000327 O
PDH
e
.
REPORT DETAILS 1.
Persons Contacted Licensee Employees
- S. Anthony, Licensing Engineer G. S. Boles, Mechanical Maintenance Supervisor
- C, R. Bryant, Power Plant Maintenance Specialist R. Landis, Construction Engineer, Modifications R. C. Murray, Engineering Aide, Mechanical Maintenance
- L. M. Nobles, Plant Manager
- R. W. Olson, Modifications Manager NRC Resident Inspectors M. Branch P. E. Harmon K. M. Jennsion
- Attended exit interview 2.
Exit Interview The inspection scope and findings were summarized on May 6,1987, with those persons indicated in paragraph 1 above.
The inspector described the areas inspected and discussed in detail the inspection findings. No dissenting comments were received from the licensee. The following new item was identified during this inspection.
Violation 328/87-28-01, Hanger Design Loads Exceeded Snubber Capacity.
The licensee did not identify as proprietary any of the materials provided to or reviewed by the inspector during this inspection.
3.
Licensee Action on Previous Enforcement Matters a.
(Closed) Violation Item 327, 328/86-24-01, Inadequate Procedure and Lack of Records Pertaining to Functional Testing of Mechanical Snubbers.
The licensee's actions to correct this violation are stated in their May 29, 1986, response to to NRC Region II.
To correct this violation, the licensee *evised Surveillance Instruction (SI) 162.2, Snubber Functional Testing (Hydraulic and Mcchanical), to describe the test method, criteria, and documentation requirement for activation testing of mechanical snubbers.
The inspector examined procedure SI-162.2 and verified that the revisions were incorporated.
Violation 327, 328/86-24-01 is close._ _ _ _ - _ _ - - _ _ _
A
.
b.
(Closed) Unresolved Item 328/86-24-02, Load Ratings of Mechanical Snubbers. Review of quality records during an inspection conducted on March 18-21, 1986 (See Inspection Report Number 50-327,328/86-24),
disclosed that the the same size mechanical snubbers had different load ratings, depending on the date of the manufacture.
These snubbers were designated as either Pre-NF or NF snubbers. The Pre-NF snubbers have lower design load ratings.
In order to evaluate this problem, licensee personnel performed a walkdown inspection and identified all Unit 2 pipe supports with pre-NF snubbers.
The location, size, and rating of the Unit 2 pre-NF snubbers were tabulated and submitted to TVA Office of Engineering desiga personnel for evaluation.
The inspector reviewed the results of the engineering evaluation during an inspection conducted November 12-14, 1986 (See Inspection Report No. 50-327, 328/86-67).
Four supports were identified during the engineering evaluation where the design loads exceeded the capacity of the installed pre-NF snubbers.
These snubbers affected pipe support numbers 2 RCH-184, 2 AFDH-229, 2 CVCH-154, and 2 CSH-457.
The inspector examined the revised hanger sketches for these supports which showed the details for the replacement of the pre-NF snubbers with new NF snubbers that meet the
current updated design loads.
The inspector also examined Field
Change Request (FCR) 4644 which was written to modify the revised
hanger sketches for hanger numbers 2 CVCH-154 and 2RCH-184.
The inspector examined support numbers 2 AFDH-229, 2 CSH-457, 2 CVCH-154
'
and 2. RCH-184 and verified that new snubbers had been installed as required by the revised hanger sketches and FCR 4644.
During the field inspection, the inspector also examined various snubbers installed on safety-relating piping systems in the Unit 2 containment
building.
These snubbers included pre-NF snubbers installed in
-
hanger numbers 2 RCH-183, 2 CCH-175, 2 CCH-201, and 2 FDH-243.
The inspector verified that these pre-NF snubber were included in the tabulation of pre-NF snubbers evaluated by the Office of Engineering.
The fact that undersized snubbers had been installed in four safety-related pipe hangers was due to inadequate design drawings for these hangers. This problem was identified to the licensee as i
a violation.
Unresolved Item 328/86-24-02 is closed and upgraded to Violation Item 328/87-28-01, Hanger Design Loads Exceeded Snubber Capacity.
c.
(0 pen) Unresolved Item 327/86-24-02, Load Ratings of Mechanical Snubbers. The licensee has initiated a field walkdown to determine the locations of installed pre-NF snubbers in Unit 1.
This work has been put on hold pending the restart of Unit 2.
This item will remain open pending completion of the Unit 1 pre-NF snubber evaluation and review by NRC Region II.
4.
Unresolved Items Unresolved items were not identified during this inspectio r
"
.
5.
Licensee Identified Item (LER)
(Closed) LER (86-046), Personnel Error Resulting in Inadequate Ver'ification of Snubber Drag Force Trending. The licensee reported to NRC Region II on November 11, 1986, that a personnel error in calculation of increase of snubber drag force since the last previously performed functional test resulted in failure to identify six snubbers which had drag forces which increased by. more than 50 percent since the last previously performed functional test.
Technical Specifications 4.7.9.e.3 and 4.7.9.f require that an engineering evaluation be performed for nubbers which show an increase in drag force of more than 50 percent s.nce the last functional test of that snubber.
The inspector identified this problem for four of the six snubbers during a review of tests results conducted during a previous inspection and identifiea it to the licensee as part of Unresolved Item 327, 328/86-24-02 (See Inspection Report Nos. 50-327/86-24 and 50-328/86-24). The inspector examined the results recorded during the 1985 functional testing conducted on the six snubbers which experienced a greater than 50 percent increase over the previous surveillance.
These results are summarized in the Table below:
TABLE Measured Acceptance Support Number Snubber Type Drag Force Criteria *
1-CCH-1044 PSA-10
330 1 FDH-204 PSA-10
330 1 SIH 109 PSA-10
330 1 SIH 110 S PSA-10
330 1 FPCH-486 PSA-3
132 2-SGBH-133 PSA-1/4
10
- Maximum acceptable drag force is 2.2 percent of snubber capacity.
Based on review of the data in the above table, all measured drag forces were well within the licensee's normal acceptance criteria.
Therefore, this problem had no safety significant. The licensee's corrective actions to prevent reoccurrence of this problem were to revise procedure SI-162.2 to clearly indicate the steps required to calculate the relative increase in drag forces. However, this increase has no significance as long as the measured drag force is less than the licensee's acceptance criteria which is based on the allowable drag force calculated during performance of the piping stress analysis. This portion of Unresolved Item 327, 328/86-24-02 is resolved by closecut of this LER. The inspector discussed this problem with the licensee during the exit interview and informed the licensee that the majority of Region II licensees have removed from their Technical Specifications the requirement for engineering evaluation of a functional test for an increase of more than 50 percent in drag force over a previous
r
.
functional test when the most recent drag test results were less than the licensee's test acceptance criteria. This analysis is still performed as a trending function to prevent snubber degradation, but is not used as test acceptance criteria.
LER 86-046 is closed.
Within the areas inspected, no violations or deviations were identified.
.
l
,
i
!
'
,
i l
l i
!
t
,
i