Letter Sequence Other |
|---|
|
Results
Other: ML20151L878, ML20215B790, ML20215B804, ML20215G101, ML20215G650, ML20215G653, ML20234D077, ML20236D570, ML20236F145, ML20236F153, ML20236F168, ML20236M855, ML20236M871, ML20237J052
|
MONTHYEARML20215G6531987-06-11011 June 1987
Trojan Nuclear Plant Evaluation of Main Feed Line Seismic Restraint Failure
Project stage: Other
ML20215B7901987-06-11011 June 1987
Forwards Evaluation Rept of Main Steam Pipe Wall Thickness, Describing Fatigue & Finite Element Analyses Performed on Affected Piping,Per ASME Boiler & Pressure Vessel Code.Affected Piping Will Be Reexamined in 1988
Project stage: Other
ML20215G1011987-06-12012 June 1987
Forwards Evaluation of Displacement at Main Feedwater Restraint SR4 in Trojan Nuclear Plant & Trojan Nuclear Plant Evaluation of Main Feed Line Seismic Restraint Failure, as Result of Failure During 1987 Refueling Outage
Project stage: Other
ML20215G6501987-06-30030 June 1987
Evaluation of Displacement at Main Feedwater Restraint SR4 in Trojan Nuclear Plant
Project stage: Other
ML20234D0771987-06-30030 June 1987
Advises That Util Agrees to Complete One of Three Listed Actions Re Resolution of Main Steam Line Wall Thickness Issue Before Startup from 1989 Refueling Outage
Project stage: Other
ML20215B8041987-06-30030 June 1987
Evaluation Rept of Trojan Nuclear Plant Main Steam Pipe Wall Thickness
Project stage: Other
ML20236F1531987-07-17017 July 1987
Final Rept Trojan Nuclear Plant SR8 Failure Root Cause Evaluation Steam Condensation-Induced Water Hammer
Project stage: Other
ML20236F1451987-07-27027 July 1987
Forwards Bechtel Western Power Corp Final Rept, Trojan Nuclear Plant SR8 Failure Root Cause Evaluation Steam Condensation-Induced Water Hammer & Impell Corp Summary Rept, Independent Review of Action Plan Items..
Project stage: Other
IR 05000344/19870261987-07-27027 July 1987
Insp Rept 50-344/87-26 on 870706-10.No Violations or Deviations Noted.Major Areas Inspected:Licensee Action on Previous Insp Findings,External & Internal Exposure Control, Control of Radioactive Matls & Contamination & ALARA
Project stage: Request
ML20236D5701987-07-27027 July 1987
Advises That Util Plans to Resolve Issue Re Code Acceptability Applications Prior to 871201.Util Will Perform Necessary Design & Order Matls to Repair or Replace Unacceptable Main Steam Line Wall Thickness Areas
Project stage: Other
ML20236L3451987-07-30030 July 1987
Summary of 870617 Meeting W/Util,Bechtel & Impell Re Results of Analyses Concerning Accumulator Fill Line Failure,Main Feedwater Failure & Main Steam Line Thin Wall at Plant.List of Attendees & Viewgraphs Encl
Project stage: Meeting
ML20236F1681987-07-31031 July 1987
Rev 1 to Summary Rept, Independent Review of Action Plan Items to Resolve Trojan Main Feedwater Piping Restraint Failure Issue
Project stage: Other
ML20237J0521987-08-21021 August 1987
Responds to Util Proposing to Resolve Issue Re Main Steam Line Wall Thicknesses Which Did Not Meet Min Requirements.Util Adequately Demonstrated That Safe Operation of Plant Until May 1989 Will Not Be Compromised
Project stage: Other
ML20237J2151987-08-21021 August 1987
Advises That Technical Issues Re Accumulator Fill Line Failure & Main Feedwater Pipe Restraint Failure Adequately Addressed by Licensee.Summary of 870617 Meeting Encl.W/O Encl
Project stage: Meeting
ML20236M8711987-11-11011 November 1987
SER Supporting Util Repairs Proposal Re Accumulator Fill Line Failures
Project stage: Other
ML20236M8551987-11-11011 November 1987
SER Supporting Util Repairs Proposal Re Main Feedwater Line Restraint Failure
Project stage: Other
ML20236M8371987-11-11011 November 1987
Forwards SERs Re Main Feedwater Line Restraint Failure & Accumulator Fill Line Failures at Plant.Repairs Proposed by Util Acceptable to Ensure Integrity of Damaged Sys for Continuing Plant Operation
Project stage: Approval
ML20151L8781988-04-15015 April 1988
Forwards Addl Info Re Six Open Items/Recommendations Noted in NRC 871111 Safety Evaluation of Failure of Main Feedwater Sys Restraint SR-8,per Commitment During Audit of long-term Pipe Support Design Verification Program in Jan 1988
Project stage: Other
1987-07-17
[Table View] |
Text
- _ _ _ _ _ - _ _ _ _
i
)
l l'
l EVALUATION OF DISPLACEMENT AT MAIN FEEDWATER RESTRAINT SR4 IN THE TROJAN NUCLEAR PLANT f
l l
l PREPARED FOR l
PORTLAND GENERAL ELECTRIC COMPANY I
l BECHTEL WESTERN POWER CORPORATION SAN FRANCISCO, CALIFORNIA JUNE 1987 Originator j
A k
Checker (
8706230338 870612
~
DR ADOCK 05000 4
EVALUATION OF DISPLACEMENT AT MAIN FEEDWATER RESTRAINT SR4 IN THE TROJAN NUCLEAR PLANT 1
l 1.
BACKGROUND l
Inspections of EBB-3-1-SR4 during the 1987 outage indicated that SR4 was l
loaded in compression.
After the load on the strut was released, the piping displaced.033".
2.
EVALUATION The residual stresses from original construction cold spring and from residual weld stresses will produce initial system shakedown during the first few years, resulting in piping displacements from initial locations.
Subsequent changes in system operation such changes in themal movements of
)
the steam generator or changes in support hardware characteristics will
(
result in further system shakedown.
In 1979, SR4 failed and was replaced with a snubber.
1 In 1982, the snubber was replaced with a strut.
Since 1982, changes which would likely result in shakedown and small displacements in the line include:
a.
Reshimming the steam generator restraints b.
Refurbishment of the steam generator snubbers c.
System operation for about 3 years with a snubber in place of a strut at SR4 d.
Normal nonlinearities and aging of the pipe support hardware The observed displacement of 0.033" was evaluated to detennine its impact on piping stresses and hanger load. The calculated pipe stress was 619 psi and the hanger load at SR4 was 0.371 kips. These stresses and loads, when added to the other normal stresses and loads, are well within the stress allowable of 15,000 psi and the restraint normal design load of 6 kips.
3.
CONCLUSION The piping movement identified on the loop A MFW line of 0.033 inches has been evaluated.
The observed small displacement is consistent with what could be expected from no'rmal system thermal shakedown and non linearities of the system.
The resulting impact on the system is bounded by the design capability.
TPF34/16-1
- - - - _ -
