ML20197E378

Pipe Whip Restraint Gaps Pressurizer Surge Line Movement

ML20197E378
Person / Time
Site:	Trojan File:Portland General Electric icon.png
Issue date:	05/29/1988
From:	Roller A PORTLAND GENERAL ELECTRIC CO.
To:
Shared Package
ML20197E371	List: ML20197E369 ML20197E378
References
TAC-68207, NUDOCS 8806080293
Download: ML20197E378 (61)

Text

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PIPE WHIP RESTRAINT CAPS PRESSURIZER SURGE LINE MOVEMENT REVISION 1 MAY 29, 1988 Trojan Nuclear Plant Nuclear Plant-Engineering Department Nuclear Division E

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Portland General Electric Company 121 SW Salmon Street

' Portland Oregon 97204 Approved:

A. N. Roller Manager 8806000293 080531 PDR ADOCK 05000344 PDR p

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s TABLE OF CONTENTS Section Title Page

1.0 INTRODUCTION

1 2.0

SUMMARY

2 2.1 Pipe Whip Restraint Gaps 2 2.2 Pressurizer Surge Line Movement 2 3.0 PIPE WHIP RESTRAINT GAPS 4 3.1 Background 4 3.2 Observations 5 3.3 Corrective Action 5 3.3.1 Piping System Evaluation 5 3.3.1.1 Gap Adequacy Determination 5 3.3.1.2 As-Found Interference Evaluation 6 3.3.1.3 Reshimming 6 3.3.1.4 Pipe and Pipe Support Structural Integrity Analysis 7

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3.3.2 Pipe Whip Restraint Evaluation 7 3.3.2.1 Existing Conditions 7 3.3.2.2 New Gaps 7 3.3.3 Inspection Program 8 3.4 Root Cause 9 4.0 PRESSURIZER SURGE LINE MOVEMENT 10 4.1 Background 10 4.1.1 Punction 10 4.1.2 Design Basis 10 4.1.3 Materials 11 4.1.4 Historical Background 11 i

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i Page Section Title 4.2 Current Observations 12 4.3. Root Cause Evaluation 13 4.4 Corrective Actions 16 Inspections / Surveys 16 ~

4.4.1 4.4.2 Piping Integrity Evaluation 17-4.4.3 Startup nuaiturias Fregram 18 5.0 TABLES 15 . 1 Pipe Whip Restraints Inside Containment 5.2 Nondestructive Examination to Confirm Piping and Whip Restraint Integrity 5.3 Pressurizer Surge Line Movement History 6.0 FIGURES 6.1 Pipe Whip Rectraint Gap Evaluation Flowchart 6.2 Typical Pipe Whip Restraint 6.3 Isometric Drawing of Pressurizer Surgo Line 6.4 Stratified Flow Profile 6.5 Pressurizer Surgo Line Monitoring Instru-mentation Locations APPENDICES A. Nuclear Quality Assurance Department Participation in Pipe Whip Restraint and Related Activities B. Description of Pressurizer Surge Line Piping Integrity Analyses ,

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1.0 INTRODUCTION

PURPOSE This report documents the Portland General Electric (PGE) investigation and evaluation of (1) the inadequate gaps identified on the whip restraints (WR) for the non-reactor coolant loop (RCL) safety-related piping inside Containment and (2) the unexpected deflection of the l pressurizer surge line at the Trojan Nuclear Plant. The report identifies the causes, corrective actions and future monitoring programs for these conditions.

BACKGROUND The Large-Bore Pipe Support Design Verification Program (LBPSDVP),

developed after the 1987 Refueling Outage, included an evaluation of the adequacy of the WR designs and their rock bolt anchorages. As a result of this evaluation, thermal and seismic piping deflections and WR gaps were calculated to be different from those used in the original design.

Field measurements of WR gaps were obtained in order to evaluate the as-built conditions with the new calculations.

During the field measurements of WR gaps, it was discovered that the pressurizer surge line WRs had gaps different from those previously measured and that WR 1 ' contact with the piping. The pressurizer surge line gaps have bt ed and evaluated during refueling outages since 1983 when evidence of piping movement had been observed.

The Nuclear Regulatory Commission's (NRC) Safety Evaluation Report (SER) dated June 16, 1986 summarizes the efforts related to the pressurizer sarge line movements to that time.

This PGE report deals with two distinct, but related, concerns:

a. Non-RCL pipe WR gaps inside Containment and the differences between [

current field measured, latest calculated, and original design values,

b. The continued unexpected detlection of the pressurizer surge line.

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2.0

SUMMARY

2.1 PIPE WHIP RESTRAINT CAPS INSIDE CONTAINMENT (excluding the l pressurizer surge line)

. Using the data for pipe deflections from the latest calculations and the WR field measurements, it was determined that the piping may contact the WR on 55 of the 134 WRs inside Containment (excluding the pressurizer surge line). The gaps on the remaining 79 WRs were adequate to preclude contact.

Evaluations will be completed prior to plant heat-up to demonstrate that the affected piping system's design is in accordance with the >

Trojan Final Safety Analysis Report (FSAR). In cases where the gaps are inadequate, reshimming will be performed before plant heat-up.

An inspection program has been established to verify adequacy of the design approach for evaluating and setting WR gaps.

2.2 PRESSURIZER SURGE LINE MOVEMENT The displacement of the pressurizer surge line and ultimate contact with the WRs has been investigated. It is concluded that the most probable cause of pressurizer surge line displacement is thermal stratification of water within the surge line.

The gaps on the pressurizer surge line WRs will be set to the maximum allowable prior to heat-up to minimize their interferences with the surge line.

Conservative analyses have demonstrated the surge line integrity in accordance with the FSAR requirements for a minimum of eight additional heatup and cooldown cycles. For reference, there have been 32 heatup and cooldown cycles since initial plant startup in 1975.

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A monitoring program will be implemented to obtain temperature and displacement data during start-up from the current. refueling outage.

The results of the monitoring program will be used to verify the assumptions made in the piping integrity and thermal stratification analyses and to provido data for further svaluations of the pressurizer surge line and surge line WRs for the full life of the plant.

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o 3.0 PIPE WHIP RESTRAINT CAPS This section discusses the WR gaps on lines inside Containment other than I the RCL or the pressurizer surge line. The evaluation and necessary reshimming of 16 reactor coolant loop WRs were completed in 1986. There are 14 WRs on systems outside Containment . The restraints on the Seismic Category I piping were evaluated for piping interference in 1987. All these WR's will be reexamined prior to heatup to confirm the gaps are acceptable. The WRs on the pressurizer surge line are discussed' in Section 4.0.

This section describes the calculated and measured gaps between piping and pipe WRs and the corrective actions taken for those WRs where the gapt were inadequate. Also described are the evaluations performed to demonstrate piping system and pipe whip restraint design adequacy.

3.1 BACKCROUND There are 134 WRs on non-RCLs. The original design (1974-75) of WRs was based on thermal movements from preliminary piping stress analyses performed by the Architect Engineer (A-E). After WR installation,-gaps were measured in both the cold and hot conditions (preoperational hot functional testing) without shims in place.

Following these measurements, the shims were installed with the plant in a cold condition. Movements as a result of seismic, thermal, and Lot. .. Coolent Accident (LOCA) or other faulted l displacements (for other than cold and hot standby conditions) were not considered in determining the shim size. The gap sires were never reconciled with the final piping analysis. As part of the LBPSDVP, the piping stress analyses were reviewed and reperformed, l if required. The revised pipe thermal and seismic movements are being used to establish the required gaps in the WRs.

1 Thirteen WRs are on the Main Steam Lines; nine of which act as a combination seismic restraint and whip restraint; eight on Seismic Category I piping; one on Nonseismic Category I piping. Four WRs are on the main steam line seismic category I piping. One WR is on feedwater piping. '

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3.2 OBSERVATIONS From an initial comparison of new pipe deflections from the latest piping analysis with the existing WR gaps (as specified on drawings), 67 of 134 WRs were found to be in contact with the piping during thermal or seismic conditions. The remaining 67 were determined to have adequate gaps. As a result, field measurements of WR gaps were performed during the 1988 Refueling Outage. Piping was found to be in contact with eight WRs in the cold condition.

Also, based on these field-measured gaps, it was determined analytically that piping could experience interference with existing whip restraints under thermal and/or seismic conditions at 47 WRs.

Of these 47, 24 were calculated to have contact for thermal movement, whereas, 23 were calculated to have contact for seismic movement only. Table 5.1 is a complete listing of all non-RCL WRs (including WRs on the pressurizer surge line) and identifies those WRs which were in cold contact or would have been in contact with the piping under thermal or seismic conditions.

3.3 CORRECTIVE ACTION 3.3.1 Piping System Evaluation 3.3.1.1 Gap Adequacy Determination Pipe movements for normal, upset, and faulted conditions were determined from the current stress l analysis calculations. Field gap measurements were obtained for all WRs, and piping interferences in all conditions were determined. The complete evaluation process is illustrated in Figure 6.1. A

typical WR is shown in Figure 6.2.

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3.3.1.2 As-Found Interference Evaluation Piping (and pipe supports) in cold contact or calculated to be in contact due to thermal or seismic conditions is being evaluated for the effects of restricted movement at WRs under all conditions.

The magnitude of piping interference in the cold condition was determined by removing the shims and noting the pipe movement. Piping stresses and pipe support loads were determined and evaluated for the effects of cold contact and thermal contact.

Stresses in all piping except for sections of the normal charging line were within code alleNables. A fatigue analysis is being conducted for the affected sections of the normal charging system piping.

Nondestructive Examination (NDE) is being conducted on he affected piping welds. The NDE of piping being performed is shown in Table b.2. The NDE inspections will be completed prior to heatup. The integrity of the piping system will be confirmed to be acceptable prior to heatup.

3.3.1.3 Reshimming The WR gaps will be adjusted by modifying shim dimensions to remove all interferences of piping with WRs in cold and hot conditions except where analyses demonstrate that code requirements are met for the piping system. Also, seismic movement interference will be removed except where the piping system is shown to be acceptable. These shim modifications will be completed prior to heatup.

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g 3.3.1.4.~ Pipe and Pipe Support Structural Integrity Analysis A structural integrity review has been performed for -

the increased loads on the pipe supports, NDE of the'one support (SA200) on the Chemical and Volume Control 1 System (CVCS) normal letdown line is being performed to ensure the support is ^ acceptable. This -

inspection will be completed prior to. plant heatup. l The' integrity of the piping system will be confirmed-

-in accordance with the TSAR. Assessment of whether the piping systems were operable during previous operating cycles will-be completed after restart.

3.3.2 Pipe Whip Restraint (WR) Evaluation 3.3.2.1 Existing Conditions The effects of a pipe in contact wit'h a WR under-cold, hot, or seismic conditions were determined to have an insignificant effect on the integrity of the WR and are bounded by.the design loads resulting from a pipe break.

3.3.2.2 New Caps l

l Reshimming will be completed to accommodate piping movement for all normal, upset, and faulted conditions as necessary to demonstrate code l requirements are met. The new gaps resulting from reshimming will be conpared with the design gaps used in the WR design calculacions. The assessment of the WR's adequacy in cases where the as-left gap is larger than the gaps used in the WR design will be 7_

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4 completed prior to heatup to confirm the design meets FSAR requirements. Any modifications identified to be necessary as part of this assessment will be performed before heatup.

WRs, which were neither found to be in cold contact nor determined to be in contact with piping under thermal or seismic conditions, were not reshinned.

The operability of these WRs for which the as-left l gap is larger than the gap used in the WR design  !

will be confirmed prior to heatup. These WR will be analysed to demonstrate they meet FSAR requirements i afterrestartandanynecessarymodifications performed in 1989 to restore design margins.

3.3.3 Inspection Program An inspection program will be implemented to ensure that adequate WR gaps exist. During the 1988 Refueling Outage, gaps in cold condition, have been verified for all WRs. For selected WRs (where practical, considering radiation exposure and personnel safety), the WR gaps will be inspected and adjacent pipe support hanger and snubber movement will be measured at hot conditions. This inspection will confirm the adequacy of the design approach used to determine the WR gaps and pipe movement.

During the next outage, selected WR gaps will be measured in the cold condition.

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.A 3.4 ROOT CAUSES The root causes of inadequate gaps for 55 of 134 pipe WRs were determined to bo due to a combination of the following:

a. Failure to reconcile the A-E determined WR gaps with the final piping analyses.

-b. Failure to provide adequate allowance for seismic induced l movements when determining gap size.

c. Incorrect gaps set during construction.

d. Cap change duo to thermal shakedown of piping system.

The gap settings for WRs had not been inspected or monitored since 1975.

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4.0 PRESSURIZER SURCE LINE MOVEMENT 4.1 BACKCROUND This section describes the design basis of the pressurizer surge line, the history of observed movements of the pressurizer surge line since 1982, the cause of the observed movements, and the analyses performed to support the cause of the movement and structural integrity of the line. This section also describes the monitoring program to be implemented.

4.1.1 Function The pressurizer surge line is designed as a flow path between the Reactor Coolant Loop (RCL) (hot leg) and the pressurizer for pressure control of the Reactor Coolant System (RCS).

4.1.2 Design Basis Design loads include pressure (2,485 psig), temperature (680*F), seismic, and design basis accident (pipe break) conditions. The American National Standards Institute (ANSI) B31.7 (1969) piping code was the original design and analysis code of record which included requirements for a detailed fatigue analysis. The American Society of Mechanical Engineers (ASME) Code,Section III (1977 Edition through 1979 Winter Addenda) has been used for analysis purposes and has been reconciled with ANSI B31.7 analysis and design requirements. In developing loads for this analysis, it was assumed that the line and attached nozzles would experience a thermal transient from overy plant event which resulted in an in-surge or out-surge of flow between the RCS and pressurizer. Thus, many cycles were assumed to occur Revision 1

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with differential temperature loadings ranging from about 300*F (during plant heatup) to about 50*F during normal power  ;

operation. In the original design analysis, the in-surges or out-surges were assumed to "sweep" the fluid in the line, resulting in uniform thermal loadings at any particular location. At that time, stratification of flow in the pressurizer surge line was not considered in the design.

The pressurizer surge line is a 14-inch Schedule 160 stainless steel pipe. The piping layout, which is typical of most Westinfhouse Pressurizer Water Reactor designs, is basically a horizontal run with several pipe bends (for thermal expansion) from the hot leg to just below the pressurizer centerline, where the line rises vertically about 7 feet 7 inches to the pressurizer nozzle. The horizontal s run is sloped upward to the pressurizer with an angle of 1

about 0.6 degrees, which results in an 8.3-inch vertical increase over 63 feet. This overall layout is depicted in Figure 6.3. The line is insulated with 4-inch-thick stainless steel encapsulated mirror-type insulation.

4.1.3 Materials The following materials were used in the pressurizer surge line design:

Surge line piping: SA 376 TP316 Surge line nozzle (RCS): 3A 182 F316 Pressurizer nozzle: SA 508 Class 2 Pressurizer nozzle safe end: SA 182 CR F316L 4.1.4 Historical Background Since 1982 '

PGE began monitoring the pressurizer surge line in 1982 following removal of the pressurizer surge line thermal Revision 1

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sleeve from the reactor coolant loop nozzle. Thermal sleeve removal was required because the sleeve welds had failed.

The NSSS Vendor demonstrated by a revised fatigue analysis that the sleeve was not necessary to protect the reactor

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coolant loop nozzle from thermal transient effects.

To remove the thermal sleeve, the surge line was cut at two locations: adjacent to the reactor coolant loop at the nozzle-to-surge.line weld and at a second point several feet away toward the pressurizer beyond a 45-degree bend. Once this section of piping had been removed, the thermal sleeve was extracted and tho line welded back in place. PCE was ,

advised at that time that some amount of thermal shakedown (ie, permanent deformation of the pipe as a result of i relaxation of internal stresses) could be expected, and therefore, it was necessary for the line to be observed and, if needed, adjustments made at the hangers and at the pipe WRs.

The surge line WRs were monitored over the next six outages.

Contact was noted between the surge line and some of its WRs each year through the 1986 Refueling Outage. For each contact, a root cause was postulated and an evaluation of the piping system was performed. In all cases, the piping system and its restraints were shown to satisfy the design limits.

A description of the surge line and WR history from 1982 to the present is provided in Table 5.3.

4.2 CURRENT OBSERVATIONS (MAY 1988)

When the plant was shut down in 1988, a general inspection of pipe WRs was performed as part of the Large-Bore pipe Support Design Revision 1 l

Verification Program. The pressurizer surge line WRs were included within this program. Contact was observed on pressurizer surge line WR 1.2. Measurement revealed an uplif t force of 4,771 pounds, and following removal of the contacting shim, the pipe moved upward an additional 3/8 inch.

4.3 . ROOT CAUSE EVALUATION There wero several proposed explanations provided as to the cause of

( the surge line movement and contact with the WRs. These possible explanations include:

l Thermal shakedown following the removal of the thermal sleeve in 1982.

Design and construction errors of the surge line whip restraints.

Abnormal movement of the reactor coolant loop or the pressurizer.

Thermal stratification of water in the surge line.

Each of these proposed causes was reviewed and conclusions on their credibility as reasons for surge line movement are discussed below.

Thermal Shakedown Removal of the thermal sleeve on the RCL nozzle required removal of a section of piping on the surge line. When the surge line was cut, cold spring in the line occurred and the piping moved outward. When ,

1 the piping was rowelded, a cold pull of approximately 7,000 lbs was required to bring the surge line into alignment with the nozzle.

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Some amount of shakedown was expected for one or two cycles after welding. The thermal sleeve was removed in 1982 and six heatup/cooldown cycles have occurred sineo that time. Since the cold spring shakedown would have occurred in one or two cycles, it was not considered to be a factor during this outage.

DesiRn and Construction Errors The pressurizer surge line WRs have been monitored regularly over the past six years, and the gaps have been reviewed. The gaps were reset consistent with the original design criteria cach time contact was found or when they wore determined to be inadequato. The design settings of the gaps are correct (under the original assumption of no thermal stratification) and are not a cause of surgo lino movement. There have been no indication that the shims for the gaps were inappropriately installed.

Abnormal Movement of the Reactor Coolant Loop or the Pressurizer The RCL motion which was oDserved in 1986 could have resulted in unexpected movements at the RCL surge line nozzle. This movement would have caused unexpected deflection of the surge line. The correct gap settings on the steam generator and hot leg whip restraint woro established and the results of the monitoring program demonstrated that the RCL moved as expected and is therefore not a cause of the unexplained surgo line motion. The pressurizer is designed to expand in the vertical direction only. Inspections of the pressurizer during the 1988 Refueling Outage indicate it is moving as designed and would not be a cause of the unexpected surge lino movement.

Thermal Stratification of Water in the SurRe Line Thermal stratification has previously been identified in the Trojan surge line. However, during evaluation of this effect, the surge line motion was not explained. A 100*F differential temperature (which was assumed at that time) across the line was not adequate Revision 1

to explain the movement. Also, the RCL restrained thermal growth was identified during this time (see abovo), and further ovaluation of stratified flow was discontinued.

Industry experience since 1987 has indicated that significant thermal stratification in the pressurizer surge line is possible.

Preliminary thermal-hydraulic calculations confirm this for typical flow rates in the surge line. Piping stress analysis modeling stratified flow has been performed which shows significantly more deflection than obtained from analysis assuming unifort temperature. This deflection increases with increating differential temperature betwoon tho top and bottom of the pipe. The evaluation indicates that the line under stratified conditions would deflect downward, contact WRs 1.2 and 1.4, and undergo p3astic deformation which would result in the cold set of the pipe above its original location. This agrees with the observed vertical set of the line at those locations in the cold condition.

Operating conditions which produce stratification occur during heatup, cooldown, and steady-state cperation of the plant. The 1985 assessment of thermal stratification had focused on hot standby and power operation during which there was a lower temperature difference because these were considered to be the limiting conditions at that time. Current effortu havo focused on plant conditions during heatup when the temperature differences between the RCL and pressurizer are larger.

During a typical plant heatup, water in the pressurizer is heated to a temperature of approximately 440*F, thermal expansion of the water occurs, and a bubble is formed in the pressurizer. Loop temperature is gradually increasing. As the water flows from the pressurizer to the loop (out-surgo), the hotter water ridos on a layer of cooler water, causing the upper part of the pipo to bo heatad to a higher temperature than the lower part of the pipe. This condition is shown in Figure 6.4 The potential differential temperature could l

be as high as 300*F, based upon plant operating limitations.

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Under these conditions, analysis has shown that differential thermal expansion of the pipe metal causes the pipe to bow, resulting in either upward or downward deflection at any point on the line, depending upon the stratification distribution and piping configuration. A description of the analysis to verify the root cause is provided in Appendix B, Section B.2.

4.4 CORRECTIVE ACTION 4.4.1 Inspection and Surveys l l

During the 1988 Refueling Outage, the following inspections and nondestructive examinations (NDEs) were performed on the pressurizer surge line:

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• Ultrasonic (UT) and dye penetrant (PT) examinations of all pressurizor surge line circumferential welds from the RCS nozzle-to-pipe wold to the pressurizer nozzle-to-pipe l weld. Table 5.2 describes the UT and PT examinations. l

• All pressurizer surge line WR gaps were measured. Contact was observed at WR 1.2.

• A visual inspection revealed no discernable distress in the piping line.

• The proscurlzer surge line WRs and hangers were visually inspected and no structural damage was found.

• The Rosetor Coolant Loop Thermal Expansion Program results were reviewed to confirm proper r.ovement of the RCL. In addition, visual inspections woro performed on the steam generator seismic restraints and upper support rings. No abnormal conditions wero found.

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-* The pressurizer anchor bolts and seismic supports were '

-checked. No abnormal conditions were found.

PGE contacted other ~ utilities with pressurized water reactors (PWRs). Several utilities confirmed the presence of thermal stratification in the pressurizer surgo lino and/or contact

• with restraints or unusual surge line motion. .

4.4.2 Piping Integrity Evaluation The root causs analysis identifies thermal stratification as the cause of the surge line movement. The analysis predicts downward motion of the surge line due to stratified flow conditions resulting in interference with the pipe WRs. The restrained thermal growth of the pipe causes a yielding in some sections of piping which produces a permanent upward set in the piping when cooldown occurs, which is consistent with the observed pipe movements.

The following analyses were performed to demonstrate the integrity of the surge line under the stratified flow conditions and existing WR gaps:

• Elastic piping analysis of the surge line to evaluate thermal expansion stresses in the piping system.

• Fatigue analysis of the piping and nozzles.

• preliminary leak-before-break assessment of the surge line piping to demonstrate leak detection and flaw stability under normal and faulted loads.

A detailed discussion of the piping integrity analyses is provided in Appendix B.

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4 The results of these evaluations concluded that the piping and nozzles satisfy ASME Code Section III limits under thermal stratification and all other design loadings for 40 plant heatup/cooldown cycles. The plant has currently experienced 32 heatup/cooldown cycles.

During plant startup, a detailed monitoring program (see Section 4.4.3) on the pressurizer surge line will verify the loading assumptions (of the near-term analysis) and provide input for final stress analyses and fatigue-life calculations.

The American Society of Mechanical Engineers (ASME) Codo qualification of this piping for the past and future design life operation will be revised.

4.4.3 Monitoring Program In order to establish the actual temperature distribution and line movements in the pressurizer surge line, a monitoring program has been developed. This monitoring program is necessary to characterize the thermal loadings to accurately evaluate the fatigue life and pipe stresses in the pressurizer surge line. Prior to this program, all piping stress analyses have included many conservative assumptiono in order to ensure that the uncertainties in the loading are bounded. This approach is ov;rly conservative for the design basis evaluation of the pressurizer surge line.

The monitoring program will acquire system operational (flow, temperature, and pressure) and displacement data. With this data, tha stratification temperature profiles, flow rates, and line movements will be identified and will be used as input to stress analysis calculations to evaluate pipe stress s and fatiguo life. The locations of resistance t

tamperatures detectors (RTDs) and the linear potentiometers are shown in Figure 6.5.

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-a The actual cold gap dimensions.at av. pipe whip restraints will be obtained. prior to plant heatup,  ;

The data will be used to ensure that the assumptions incorporated in the bounding stress analyses are conservative, i

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TABLE 5.1 TROJAN InfCLEAR PLANT 'Page 1 of 19l

- Pipe hip Restraints (Mts)

Pipe Wt Reshim No. seuuber System PSIO ' Isometric leo. Contact Required Remarks 1 1.1 Pressurizer Surge Line (14-inch line) M-201 sh 182 RC-2501R-20-1 Thermal +5eismic Yes 2 1.2 Pressurizer Surge Line (14-inch line) M-201 sh 142 RC-2501R-20-1 Cold Contact Yes 3 1.3 Pressurizer Surge Line (14-inch line) M-201 sh 1&2 K-2501R-20-1 leo leo 4 1.4 Pressurizer Surge Line (14-inch line) M-201 Sh 142 RC-2501R-20-1 Seismic Yes 5 1.5 Pressurizer Surge Line (14-inch line) M-201 Sh 142 RC-2501R-20-1 No les 6 1.6 Pressurizer Surge Line (14-inch line) M-201 Sh 142 .RC-2501R-20-1 Seismic Yes 7 1.7 Pressurizer Surge Line (14-inch line) M-201 Sh 142 RC-2501R-20-1 No . sto 8 1.8 Press'srizer Surge Line (14-inch line) M-201 Sh 142 RC-2501R-20 -1 Thermal +5eismic .Yes-9 3.1 Residual Heat Removal systen Suction M-201 sh 1 AC-2501R-13-1 Seismic leo causes'2 and 3. l from Reactor Coolant System Loop D M-205 (14-inch line) 10 4.1 Accumulator Safety Injection to Loop 8 M-201 Sh 1 AC-2501R-2-3 Seismic Yes causes 1, 2, and 3.

(10-inch line) l' Causes:

1. Gaps set wrong during construct % .

2. Actual gaps set based upon TWT did not account for maximum thenaal displacement (no reconcillation).

3. Iso allowance for seismic movement when original gaps were established by design.

4. Cold gaps have changed due to thermal shakedown of piping system.

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TABLE 5.1 TROJAN NUCLEAR PLANT Page 2 of 19:

Pipe Whip Restraints (WRs)

Pipe WR Reshim No.  % seer System P&ID Isometric No. Contact Required Remarks 11 4.3 SafetyinjectiontoReactorCoolant M-201 Sh 1 SI-2501R-2-2 No No Loop (10-inch line) M-206 sh 1 12 4.4 Safety Injection to Reactor Coolant M-201 Sh 1 SI-2501R-2-2 Seismic Yes causes 2, and 3. l

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Loop B (10-inch line) M-206 Sh 1 13 5.1 Residual Heat Removal System M-201 Sh 1 51-2501R-31-4 No No (6-inch line) M-205 14 5.11 Residual Heat Removal System M-201 sh 1 SI-2501R-31-3 No No (f>-inch line) M-205 15 5.12 Residual Heat Removal System M-201 sh 1 51-2501R-31-3 No No (6-inch linc) M-205 16 5.13 Resittual Heat Removal System M-201 sh 1 SI-2501R-31-3 No No (6-inch line) M-205 17 5.2 Residual Heat Removal System M-201 Sh 1 51-2501R-31-4 No No (6-inch line) M-205 Caus:s:

1. Gaps set cong during construction.

2. Actual gaps set based upon HFT did not account for maximan thermal displacement (no reconciliation).

3. No allowance for seismic movement when original gaps were established by design.

4. Cold gaps have changed due to thermal shakedown of piping system.

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TABLE 5.1 TROJAN NUCLEAR PLANT Page 3 of 19 Pipe 1 Alp Restraints (WRs)

Pipe WR Reshim No. Number System P&lD Isometric No. Contact Required Renarts 18 5.3 Residual Heat Removal System M-201 Sh 1 SI-2501R-31-4 Seismic Yes causes 2 and 3. l (6-inch line) M-205 19 5.4 Residual Heat Removal System M-201 Sh 1 SI-2501R-31-4 Cold Contact Yes Causes 1, 2, 3, and 4.

l (6-inch line) M-205 20 5.5 Residual Heat Removal System M-201 sh 1 SI-2501R-31-4 Seismic Yes causes 2 and 3. l (6-inch line) m205 21 5.6 Residual Heat Removal System M-201 Sh 1 51-2501R-31-4 No No (6-inch line) M-205 22 5.7 Residual Heat Removal System M-201 Sh 1 SI-2501R4 e-4 No No (6-inch line) M-205 23 5.8 Residual Heat Removal System M-201 sh 1 SI-2501R-31-4 Thennal+5eismic Yes causes 1 and 3.

(6-inch line) m205 24 6.1 Safety Injection to Reactor Coolant 5 201 sh 1 SI-2501R-2-1 Thennal+5eismic Yes causes 1, 2, 3 , and 4.

Loop (10-inch line) 5206 sh 1 Causes:

1. Caps set wrong during construction.

2. Actual gaps set based upon HFT did not account for maximum thennal displacement (no reconciliation).

3. No allowance for seismic movement when original gaps were established by design.

4. Cold gaps have changed due to thennal shakedown of piping system.

Revision 1

a TABLE 5.1 TROJAN NUCLEAR PLANT Page 4 of 19 Pipe Whip Restraints (WRs)

Pipe Mt Reshim No. Nimber_ System P&ID !sometric No. Contact Required. Remarks 25 6.2 Safety Injection to Reacter coolant M-201 Sh 1 SI-2501R-2-1 No No Loop (10-inch line) 5206 Sh 1 26 6.3 SafetyInjectiontoReactorCoolant 5201 Sh 1 SI-2501R-2-1 No No Loop (10-inch line) 5206 Sh 1 27 6.4 Safety Injec',lon to Reactor Coolant M-206 Sh 1 SI-601R-1-1 No No Loop A (10-inch line) 28 6.5 Safety Injection to Reactor Coolant 5206 sh 1 5!-601R-1-1 Seismic Yes Causes 2 and 4. l Loop A (10-inch line) 29 7.1 SafetyInjectiontoReactorCoolant M-201 Sh 1 SI-250lR-2-4 No No Loop D (10-inch line) M-206 sh 1 30 7.2 Safety Injection to Reactor Coolant 5201 "h 1 SI-250lR-2-4 Seismic Yes cause 3. l Loop D (10-inch line) M-206 Sh 1 31 7.3 Safety Injection to Reactor Coolant 5201 Sh 1 51-2501R-2-4 Seismic Yes Causes 2 and 3. l Loop D (10-inch line) M-206 sh 1 Caus s:

1. Gaps set wrong during construction.

2. Actual gaps set based upon HFT did not account for maximme thervial displacement (no reconciliation).

3. No allowance for seismic movement when original gaps were established by design.

4. Cold gaps have changed due to thernial shakedown of piping system.

Revision 1

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i TABLE 5.1 TROJM NUCLEAR PLANT Page.5 of 19 Pipe Whip Restraints (lets)

Pipe WR Reshim No. Number System P&ID Isometric No.__

Contact Required Remarks 32 7.4 SafetyInjectiontoReactorCoolant M-201 sh 1 SI-2501R-2-4 No No Loop D (10-inch line) M-206 Sh 1 33 7.5 Safety Injection to Reactor Coolant M-201 Sh 1 SI-2501R-2-4 No No Loop D (10-inch line) M-206 Sh 1 34 9.1 Residual Heat Removal System to M-201 Sh 1 SI-250lR-31-5 No No Loop C (6-inch line) M-205 35 9.10 Residual Heat Removal System to M-201 Sh 1 SI-250lR-31-5 No No Loop C (6-inch line) M-205 36 9.11 Residual Heat Removal System to M-201 sh 1 SI-250lR-31-5 No No Loop C (6-inch line) M-205 37 9.12 Residual Heat Removal System *o M-201 Sh 1 SI-250lR-31-5 Saismic Yes Loop C (6-inch line) M-205 38 9.13 Residual Heat Removal System to M-201 Sh 1 SI-250lR-31-5 Seism2 c Yes Loop C (6-inch line) M-205 Causes:

1. Caps set wrong during construction.

2. Actual gaps set based upon HFT did not account for maximum thennal displacement (no reconciliation).

3. No allowance for seismic movement when original gaps were established by design.

4. Cold gaps have changed due to thennal shakedown of piping system.

Revision 1

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TABLE 5.1 TROJRN NUCLEAR PLANT Page 6 of 19 Pipe hip Nestraints (Wts)

Pipe Wt Reshim No. mer System P&ID Isometric No. Contact Nequired Remarts 39 9.14 Residual Heat Removal System to M.201 Sh 1 SI-2501R-31-5 No 'No Loop C (6-inch line) M-205 40 9.15 Residual Heat k-aval System to M-201 sh 1 SI-2501R-31-5 No No Loop C (6-inch line) M-205 41 9.16 Residual Heat Removal System to M-201 sh 1 SI-2501R-31-5 Seismic Yes causes 2 and 3 l Loop C (6-inch line) M-205 42 9.2 Residual Heat Removal System to M-201 Sh 1 SI-2501R-31-5 No No Loop C (6-inch line) M-205 43 9.4 Residual Heat Removal System to M-201 sh 1 SI-2501R-31-5 Therinal+5eismic Yes cause 2 l Loop C (6-inch line) M-205 44 9.5 Residual Heat Removal System to M-201 Sh 1 SI-2501R-31-5 Seismic Yes cause 3 l Loop C (6-inch line) M-205 45 9.6 Residual Heat Removal System to M-201 Sh 1 SI-2501R-31-5 No No l Loop C (6-inch line) M-205 l

l t

Caus2s:

1. Gaps set wrong during constrettion.

2. Actual gaps set based upon HFT did not account for maximum thermal displacement (no reconciliation)'.

3. No allowance for seismic movement when original gaps were established by design.

4. Cold gaps have changed due to thermal shakedown of piping system.

Nevision 1 4

e TABLE 5.1 TROJAN 9AICLEAR PLANT Page 7 of 19 Pipe h ip Restraints (WRs)

Pipe let Reshim No. Nunber System P&ID Isometric No. Contact Required Remarks 46 9.7 Pesidual Heat Removal System to M-201 Sh 1 SI-2501R-31-5 Thermal +5eismic Yes causes 2 and 3. l Loop C (6-inch line) M-205 47 9.8 Residual Heat Removal System to M-201 Sh 1 SI-2501R-31-5 Thermal +5eismic Yes cause 3. [

Loop C (6-inch line) M-205 48 9.9 Residual Heat Renoval System to M-201 sh 1 51-2501R-31-5 Seismic Yes cause 3.

Loop C (6-inch line) M-205 l 49 10.1 Residual Heat Removal System to M-205 SI-250lR-31-1 Thennal+5eismic Yes Causes 1, 2, and 3. l Loops C and D (8-inch line) 50 11.1 Residual Heat Removal System to M-201 sh 1 SI-2501R-31-6 No No Loop D (6-inch line) M-205 51 11.2 Residual Heat Removal System to M-201 Sh 1 SI- 2501R-31-6 Thennal+5eismic Yes causes 2 and 3. l Loop D (6-inch line) M-205 l

52 12.1 Safety Injection to the Reactor M-201 RC-2501R-1-10 No No Coolant Loop Hot Leg (6-inch line)

Caises:

1. Gaps set wrong during construction.

2. Actual gaps set based upon HFT did not account for maimum thennal displacement (no reconciliation).

3. ca allowance for seismic movement 62en original gars were established by design.

4. Cold gaps have changed due to thennal shakedown of piping system.

RevisionIl

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'e TA8tE 5.1 TROJNI NUCLEAR PLANT Page 8 of 19 Pioe E ip Restraints (W s)

Pipe W Reshim

_Nou Nuit:s r_ System P&IU Isometric No. Contact Required Remarks 53 12.2 Safety Injection to the Reactor M-201 RC-2501R-1-10 No No Coolant Loop Hot Leg (6-inch line) 54 14,1 Safety Injection to the Reactor M-201 Sh 1 SI-2501R-2-3 No No Coolant Loop (10-inch line) M-206 sh 1 55 14.2 Safety Injection to the Reactor M-201 Sh 1 SI-2501R-2-3 Seismic Yes causes 2, 3, and 4. l Coolant Loop (10-inch line) M-206 Sh I 56 14.3 Safety Injection to the Reactor M-201 Sh 1 SI-2501R-2-3 Thennal+5eismic Yes causes 2 and 3. l Coolant Loop (10-inch line) M-206 sh 1 57 14.4 Safety Injection to the Reactor M-201 Sh 1 SI-2501R-2-3 No No Coolant Loop (10-inch line) M-206 sh 1 58 14.5 Safety Injection to the Reactor M-201 Sh 1 SI-2501R-2-3 No No Coolant Loop (10-inch line) M-206 Sh 1 59 16.1 Chemical Voltane Control System M-201 Sh 2 CS-250iR-4-60 seismic No cause 3.

A::xil!ary spray (2-inch line) M-202 Sh 2 [

Causes:

1. Gaps set wrong during construction.

2. Actual gaps set based upon HFT did not account for maximum thennal displacement (no reconciliation).

3. No allowance for sei aic movement when original gaps were established by design.

4. Cold gaps have changed due to thermal shakedown of piping system.

Revision 1 l

l

TABLE 5.1 TROJAN NUCLEAR PLANT Page 9 of 19 Pipe h ip Restraints (WRs)

Pipe let Reshim No. Number systen Pt!O Isometric No. Contact hquired feemarts 60 16.2 Chemical volume Control Systen M-201 Sh 2 RC-2501R-4-60 1hennal+5eismic Yes cause 1. l Auxiliary Spray (2-inch line) 61 16.3 Chemical Volume Control System 4 201 C5-2501R-4-60 Thennal+5eismic Yes cause 3.

Auxiliary Spray (2-inch line)  % 201 Sh 2 [

62 16.4 Chemical Volume Control System 5201 sh 2

) C5-2501R-4-60 No No Auxiliary spray (2-inch line) m202 63 16.5 Chemical Volume Control system 5201 sh 2 C5-2501R-4-60 Thermal +5eismic Yes

] Auxiliary spray (2-inch line) M-202 i 64 16.6 Chemical Volume Control System  % 201 Sh 2 C5-2501R-4-60 No No 1 Auxiliary spray (2-inch line) 5202 65 16.7 Chemical Volume contro! System A202 C5-2501R-4-61 No No

] Auxiliary spray (2-inch line) j 66 17.1 Pressurizer Spray (4-inch line) E201 sh 142 RC-2501R-4-2 Seismic .No causes 3 and 4. l l

i I

! Causas:

1. Gaps set wrong during construction.

2. Actual gaps set based upon HFT did not account for maximum thermal displacement (no reconciliation).

3. No a11cuence for seismic movement when original gaps were established by design.

4 Cold gaps have changed due to thermal shakedown of piping systen.

Nevision 1

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TABLESJ TROJAN NUCLEAR PtMT Page 10 of 19 Pipe idhip Restraints (lats)

Pspe IdR Reshim No. Nuder Systen P&lD isometric No. Contact Required Remarks 67 17.12 Pressurizer Spray (4-inch line) M-201 sh 142 RC-2501R-4-2 No No 68 17.14 Pressurizer Spray (4-inch line) 5 201 sh 142 RC-2501R-4-2 No No 60 17.18 Pressurizer Spray (4-inch line) M-201 sh 142 RC-2501R-4-2 No No 70 17.19 Pressurizer Spray (4-inch line) M-201 sh 142 RC-2501R-4-2 No No 71 17.2 Pressurizer Spray (4-inch line) M-201 sh 182 RC-2501R-4-2 No No 72 17.20 Pressurizer Spray (4-inch line) M-201 sh 142 RC-2501R-4-1 No No 73 17.21 Pressurizer Spray (4-inch line) M-201 Sh 1&2 RC-2501R-4-1 Cold contact Yss Causes 1 and 4.

l 74 17.22 Pressurizer Spray (4-inch line) M-201 sh 142 RC-250lR-4-1 No No 75 17.23 Pressurizer Spray (4-inch line) M-201 sh 182 RC-2501R-4-1 Seismic No 76 17.24 Pressurizer Spray (4-inch line) 5201 sh 142 RC-25011:-4-1 Thennal+5elsmic Yes Causes 2 and 3.

l-Causes:

1. Gaps set unmg during construction.

2. Actual gaps set based upon HFT did not account for maximum therinal displacement (ro reconciliation).

3. No allowance for seismic movement when original gaps were established by design.

4. Cold gaps have changed due to therinal shakedown of piping systen.

Revision 1

T TAttE 5.1 TROJAN NUCLEAR PLANT Page 11 of 19 Pipe Whip Restraints (.JRs)

Pipe nft Reshias No. Neber_ Systen P&lD Isometric No. Contact Required Remarks 77 17.25 Pressurizer Spray (4-inch line) U201 sh 182 RC-2501R-4-1 No No ,

78 17.3 Pressurizer Spray (4-inch line) U201 Sh 1&2 RC-2501R-4-1 No No 79 17.4 Pressurizer Spray (4-inch line) U 201 sh 152 RC-2501R-4-1 No No 80 17.5 Pressurizer Spray (4-inch line) U201 Sh 142 RC-2501R-4-1 Cold Contact Yes causes 2 and 4. [

]

81 17.6 Pressurizer Spray (4-inch line) O201 sh 1&2 RC-2501R-4-1 Therinal+5eismic Yes C::use 1. l l 82 17.7 Pressurizer Spray (4-inch line) U201 sh 182 RC-250lR-4-1 No No 83 17.8 Pressurizer Spray (4-inch line) M-201 sh 182 RC-2501R-4-2 No No i

! 84 17.9 Pressurizer Spray (4-inch line) M-201 sh 1&2 RC-2501R-4-2 No No l

1 l 85 18.1 Chemical volane Control System M-202 C5-2501R-6-1 Seismic Yes Cause 3. l

] Alternate Charging (3-inch line) 86 18.2 Chemical Volume Control System U202 CS-2501R-6-1 Thermal +5eismic Yes causes 2 and 3. l Alternate Charging (3-inch line) l 1

Causes:

! 1. Gaps set wrong during construction.

2. Actual gaps set based upon HFT did nrA account for maximum therinal displacement (no reconciliation).

, 3. No allowance for seismic movement when original gaps were established by design.

4. Cold gaps have changed due to therinal shakedown of piping systen.

Revision 1.

i

TABLE 5.1 TROJAN NUCLEAR PLANT Page 12 of 19 Pipe Whip Restraints (WRs)

Pipe WR Reshim No. Ntstber System P&ID Isometric No. Contact Required Remarks 87 18.3 Chemical volume Control System M-202 C5-2501R4-1 Thermal +5eismic tes causes 2 and 3. l Alternate Charging (3-inch line) 88 18.4 Chemical Volume Control System M-201 Sh 1 RC-2501R4-1 No No Alternate Charging (3-inch line) M-202 89 19.1 Chemical volume Control System M-201 Sh 1 RC-2501R-54 Seismic No cause 3.

l Nonnal Charging (3-inch line) M-202 90 19.2 Chemical volume Control System M-202 C5-2501R-5-7 Thermal +5eismic Yes causes 2 and 3.

l Nonntl Charging (3-inch line) 91 19.3 Chemical volume control System M-202 C5-250lR-5-7 No No Nonnal Charging (3-inch line) 92 19.5 Chemical Voltsne control System M-201 Sh 1 RC-2501R-54 No No Normal Charging (3-inch line) M-202 93 19.6 Chemical Volume Control System M-201 Sh 1 RC-2501R-54 Thennal+5eismic Yes causes 2 and 3. l Honnal Charging (3-inch line) M-202 Causes:

1. Gaps set wrong during construction.

2. Actual gaps set based upon HFT did not account for maximum thennal displeament (no reconciliation).

3. No alloecance for seismic movement when original gaps were established by design.

4. Cold gaps have changed due to thennal shakedown of piping system.

Revision 1

.o TASTE 5.1' TROJAN NUCLEAR PIANT Page 13 of 19 Pipe Whip Restraints (Wts)

Pipe NR Reshim No. Number System PSIO Isenetric No. Contact Required Romerts 94 20.1 BoronInjection(1-1/2-inchline) 5 201 sh 1 RC-2501R-3-60 No No 95 21.1 Boron Injection (1-1/2-inch line) 5201 Sh 1 RC-2501R-3-60 Seismic Yes

% 22.1 BoronInjection(1-1/2-inchline) 520! Sh 1 RC-2501R-340 No No 97 24.1 Residual Heat Removal System to 5 201 Sh 1 SI-2501R-144 No No Reactor Coolant Loop Cold Leg A206 Sh 2 (2-inch line) 98 24.2 Residual Heat Removal System to A201 Sh 1 SI-2501R-144 No No Reactor Coolant Loop Cold Leg A206 Sh 2 (2-inch line) 99 24.3 Residual Heat Removal System to %201 Sh 1 SI-2501R-145 No No Reactor Coolant Loop Cold Legs 5206 Sh 2 (2-inch line) 100 24.4 Residual Heat Removal System to M-201 Sh 1 51-2501R-145 No No Reactor Coolant Loop Cold Legs 5206 sh 2 (2-inch line)

Causes:

1. Gaps set wrong during construction.

2. Actual gaps set based upon HFT did not account for maximum thermal displacement (no reconciliation).

3. No allower.ce for seismic movement when original gaps were estabilshed by design.

4. Cold gaps have changed due to thermal shakedown of piping system.

Revision 1 g

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.~

• l TABLE 5.1 TROJAN NUCLEAR PLANT Page 14 of 19 Pipe Whip Restraints (lats)

Pipe let Peshim No. Nunter System P&ID Isometric No. Contact Required. Remarks 101 25.1 Residual Heat Removal System to M-201 Sh 1 SI-250lR-144 No No Reactor Coolant Loop Cold Legs M-206 Sh 2 (2-inch line) 102 25.2 Residual Heat Removal System to M-201 Sh 1 SI-2501R-144 No No Reactor Coolant toop Cold Legs M-206 sh 2 (2-inch line) 103 25.3 Residual Heat Removal System to M-201 sh 1 SI-2501R-145 No No Reactor Coolant Loop Cold Legs M-206 Sh 2 (2 inch Il v) 104 25.4 Residual deat Removal System to M-201 Sh 1 51-25012-1 4 5 Thennal+5eismic Yes Cause 4.

Reactor colant Loop Cold Legs M-206 sh 2 l

(2-Ixh line) 105 32.1 Reactor Coolant Pamp Seal Water to M-203 CS-2501R-2844 No No Pump "C" (2-inch line) 106 32.2 Reactor Coolant Pw p Seal t;ater to M-203 C5-2501R-2844 No No Pop *C* (2-inch line)

Causes:

1. Gaps set wrong during construction.

2. Actual gaps set based upon HFT did not account for maximum thermal displacement (no reconcillation). 'I

3. No allowance for seismic movement when original gaps were estabilshed by design.

4. Cold gaps have changed due to thennel shakedown of piping system.

Revision 1

TABLE 5.1 TROJRN NUCLEAR PLANT Page 15 of 19 Pipe Whip Restraints (WRs)

Pipe WR Reshim No. Nw6er System PtiO __ Isometric No. Contact Required Remarks 107 33.1 Reactor Coolant Pup Seal hier to 5 203 C5-250lR-28-66 Seismic No Pep *D" (2-inch line) 108 33.2 Reactor Coolant Pwp Seal Water to 5203 C5-2501R-28-67 Cold Contact Yes Causes 3 and 4.

l Pop "D" (2-inch line) 109 33.3 Reactor Coolant Pung Seal mter to 5 203 C5-2501R-28-66 Thennal+5eismic Yes Pwp *D" (2-inch line) 110 40.1 Chanical volume Control system m201 sh 1 RC-2501R-10-1 No No Nonnel Letdown (3-inch line) M-202 III 40.2 Chemical Volume Control System U201 Sh 1 RC-2501R-10-1 No No Nonnel tetdown (3-inch 11pe) U202 112 40.7 Chemical Volume Control System 5201 sh 1 RC-2501R-10-1 No No Nonnel tetdown (3-inch line) 5202 113 41.1 Chemical Volume Control System 5202 C5-2501R-10-I Seismic Yes cause 3.-

l Monna1 Letdown (3-inch line)

Causes:

1. Gaps set wrong during construction.

2. Actual gaps set based upon HFT did not account for maxianan thennat displacement (no reconciliation).

3. No allowance for seismic movement when original gaps were established by design.

4 Cold gaps have changed due to thennel shakedown of piping system.

Rev hion 1

s TABLE 5.1 TROJAN NUCLEAR PLANT Page 16 of 19 Pipe Whip Restraints (65ts)

Pipe nst Reshim No. Number System P&ID isometric No. Contact Required Remarks 114 41.2 Chemical Volume Control System M-202 CS-250lR-10-1 No No Nonnal Letdown (3-inch line) 115 41.3 Chemical Volume Control System M-202 CS-2501R-10-1 No No Nonnal Letdown (3-inch lisw.r) 116 41.4 Chemical Volume Control System M-202 CS-250lR-10-1 ho No Nonnal Letdown (3-inch line) 117 41.5 Chemical Volume Control System M-202 CS-25: A- o-1 No No -

Nonnal Letdown (3-inch line) 118 41.6 Chemical Volume control System M-202 CS-2501R-10-1 No No Nonnal Letdown (3-inch line) 119 48.1 Chemical volume contrul System M-292 CS-250lR-4-50 . No No Letdown (2-inch line) 120 48.2 Chemical Voltane Control System M-202 CS-250lR-4-50 No No tetdown (2-inch line)

Causts:

1. Gaps set wrong during construction.

2. Actual gaps set based upon HFT did not account for. maximum thertaal displacement (no reconciliation).

3. No allowance for seismic movement when original gaps were established by design.

4. Cold gaps have changed due to thennal shakedown of piping system.

Revision 1

1 TABLE 5.1 TROJAN NUCLEAR PLANT Page 17 of 19 Pipe Wh h Restraints (WRs)

Pipe WR Reshim No. Nunber System P&ID Isometric No. Contact ReqJired. Remarks 121 48.3 Chemical Volume Control Sy: tem F?O2 CS-2501R-4-50 Cold contact No WR also acts as pipe support; Letdown (2-inch line) contact is acceptable.

122 48.4 Chemical Volume Control System M-202 CS-250lR-10-2 Cold Contact Yes Cause 1. l Letdown (3-inch line) 123 49.1 Steam Generator Blowdown (2-inch line) M-208 Sh 1 EBE4-E59 Thennal+5cismic Yes cause 4.

l 124 49.2 Steam Cenerator Blowdown (2-inch line) M-208 sh 1 EBE4-659 Thennal+ Seismic Yes CZJses 2 and 3.

.l-125 49.3 Steam Generator Blowdown (2-inch line) M-208 Sh 1 EBE4-659 No No 126 49.4 Steam Generator Blowdown (2-inch line) M-208 Sh 1 EBE-6-659 No No 127 49.5 Steam Generator Blowdown (2-inch line) M-208 Sh 1 EBE4-659 Cold contact Yes Cause 4.

l 128 50.1 Steam Generator Blowdown (2-inch lina) M-209 Sh 1 EBE4-661 No No 129 50.2 Steam Generator Blowdown (2-inch line) M-208 Sh 1 EBE-6-661 Seismic No -Cause 3.

l 130 50.3 Steam Generator Blowdown (2-inch line) M-208 Sh 1 EBE-6-661 No No causts:

1. Gaps set wrong during construction.

2. Actual gaps set based upon HFT did not account fc.*im imum theraal displacement (no reconciliation).

3. No allowance for seismic movement when original gaps were established by design.

4. Cold gaps have changed due to thermal shakedown of piping systesa.

Revision 1

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TABLE 5.1 TROJAN NUCLEAR PLANT Page 18 of 19 Pipe Whip Restraints (WRs)

Pipe WR Reshim

_No Nunber System P&lD Isometric No. Contact Required Remarks 131 51.1 Steam Generator Blowdown (2-inch line) M-208 sh 1 EBE-6-654 No No M-348 132 51.2 Steam Generator Blowdown (2-inch line) 5 209 Sh 1 EBE-6-660 No No 133 51.3 Steam Generator Blowdown (2-inch line) M-208 Sh 1 EBE-6-660 No No 134 51.4 Steam Generator Blowdown (2-inch line) 5208 sh 1 EBE-6-660 Cold Contact 'Yes Cause 4. l 135 52.1 Steam Generator Blowdown (2-inch line) 5208 Sh 1 EBE-6-650 No No M-348 136 52.2 Steam Generator Blowdown (2-inch 15.e) 5 208 Sh 1 EBE-6-650 No No M-348 137 52.3 Steam Generator Blowdown (2-inch line) M-208 Sh 1 EBE-6-662 No No 138 53.1 Main Steam (28-inch line) 5208 EBB-1-1 Thermal + Seismic Yes Causes 1, 2, and 3. l 139 54.1 Feedwater (14-inch line) 5208 Sh 1 EBB-3-1 Thermal + Seismic Yes Causes 2 and 3.

&213 sh 2 l

Causts:

1. Gaps set wrong during construction.

2. Actual gaps set based upon HFT did not account for maximum thermal displacement (no reconciliation).

3. No allowance for seismic movement when original gaps were established by design.

4. Cold gaps have changed due to thermal shakedown of piping system.

Revision 1

TABLE 5.1 TROJAN NUCLEAR PLANT Page 19 of 19 Pipe Whip Restraints (WRs)

Pipe WR Reshim No. Number System P&ID Isometric No. Contact Required Renarks 140 54.2 Feedwater (14-inch line) M-?O8 Sh 1 EB8-3-1 Thennal+5eismic Yes causes 2 and 3. l M-213 sh 2 141 54.3 Feedwater (14-inch line) h-208 Sh 1 EBB-3-1 No No M-213 sh 't 142 54.4 Feedwater (14-inch line) M-208 sh 1 EBB-3-1 No No M-213 sh 2 2360W l

Ca'csts:

1. Gaps set wrong during construction.

2. Actual gaps set based upon HFT did not account for maximum thermal displacement (no reconciliation).

3. No allowance for seismic movement when original gaps were established by design.

4. Cold gaps have changed due to thermal shakedown of piping systen.

Revision 1 l

+

A - _ _ _ _ _ ____ _ ___ ____ m . _ _ _ _

i Table 5.2 Page 1 of 2-NCKnESTRUCTIVE EXeralATION TO CONFIIWI PIPIIIG INTEGRITY Isometric Weld No. Type of Inspectio9 System / Whip Restraints Reason Results RC-250lR-20-1 FW-P12220 UT, PT Pressurizer Surge Pressurizer Surge Line unusual FW-P12221 UT, PT Line/WR 1.1, 1.2, movement FW-5273 UT, PT 1.4, 1.6, 1.8 FW-5274 UT, PT TW-5275 UT, PT FW-5276 UT, PT Shop weld below UT, PT PWR 1.7.

Shop weld t!f, PT between PWR 1.4 and H-2.

C5-250lR-5-7 FW-F43318 UT and PT CVCS Nonnal NSSS Calculation WF showed

• RC-250lR-5-6 FW-F43319 UT and PT Charging /WR 19.2 overstressed (over design limits) l FW-F43250 UT and PT at these welds because of whip FW-F43251 UT and PT restraint contact FW-F15094 UT and PT FW-5164 UT and Pi FW-5165 UT and PT FW-5166 UT and PT FW-F43320 UT and PT FW-F43321 UT and PT Revision 1

Table 5.2 Page 2 of 2-NONDESTRUCTIVE EXMINATION TO CONFIM PIPING INTEGRITY Isometric Weld No. type of in>pection SystenMhip Restraints Reason Results CS-250lR-5-7 FW-5167 UT e/t PT .

• RC-250lR-5-6 *FW-A, Spool 2 UT and PT

• FW-8, Spool 2 UT and PT

• FW-C, Spool 2 UT and PT

• FW-F, Spool 2 UT and PT CS-250lR-10-2 Pipe Support PT CVCS Nonnal Letdown A-E Calculation 5-1 shows that SA 200 Stanchion the stress levels for the struc-to Pipe. tural welds on the support exceed (No weld No.) structural integrity limits All structural PT welds on Support SA200.

2371W Revision I

TABLE 5.3 Page 1 of 2-PRESSURIZER SURCE LINE AND PIPE WHIP RESTRAINT HISTORY Restraints Date Contacted Action Taken Postulated Root Cause Observations Comments 05/82 N/A Surge line nozcle N/A N/A N/A thermal liner removed.

Pipe cut and rewelded.

11/82 1.4 Analyzed stresses. Thermal shakedown. Top of pipe had Evaluation indicated no-contacted WR. problem.

01/83 1.2, 1.4 Restraints reshimmed: Thermal shakedown N/A 1.2 - moved 17/32 in. due to rewelding of from top to bottom. surge line after 1.4 - moved 3/4 in, removal of thermal from top to bcttom. liner.

05/84 1.2 Restraint reshimmed: Thermal shakedown N/A l

1/4 in. shim removed. due to rewelding of l surge line af ter removal of thermal liner.

l Thermal AT = 100*F hot Analysis indicated that l 05/85 1.1, 1.4 stratificatiori. standby. thermal stratification AT = 50*F power. could not cause observed pipe movement. Analysis of as-found condition I indicated piping within design stress limits.

Indication of. potential RCL movement was identified based upon observed condition of hot leg whip restraint and on steam generater snubber results.

1 l

TABLE 5.3 Page 2 of 2 PRESSURIZER SURGE LIFR AND PIPE WHIP RESTRAINT HISTORY Restraints Date Contacted Action Taken Postulated Root Cause Observations Comments 05/86 1.4 Restore restraint Reactor Coolant Thermal growth of Analysis indicated surge clamp. Prepare fur Locp B hot leg hot leg was restrained line would not move-as replacement in 1987. motion at surge- by inadequate gaps on observed. Analysis of line nozzle. steam generator. as-found condition showed surge line j within acceptable _i stress limits. The' '

monitoring program to measure RCL motion at the steam generator supports and hot leg whip restraint was initiated.

i l 05/87 1.4 Restraint clamp N/A N/A N/A replaced as planned.

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. APPENDIX A NUCLEAR QUALITY ASSURANCE DEPARTMENT PARTICIPATION IN PIPE WHIP RESTRAINT AND RELATED ACTIVITIES The Nuclear Quality Assurance Department (NQAD) has independently monitored and evaluated the activities surrounding the pipe whip restraint gap evaluation and pressurizer surge line movement to ensure quality is maintained. The following is a list of Quality Assurance (QA) and Quality Control (QC) activities related to the pipe whip restraints' pressurizer surge line movement and related issues.

1. Moritoring of the Reactor Coolant Loop Thermal Expansion Test Program in 1986, to confirm the proper movement of the RCL.

2. Technical Assessment of Architect-Engineer (A-E) in June 1987, to ensure that the engineering work associated with the review of pipe supports designed by the Civil Engineering discipline was being performed properly.

3. Audit and technical quality review of the Large-Bore Pipe Support Verification Program in August 1987 to evaluate the A-E pipe support design verification program.

4. Audit and technical review of A-E engineering activities in October 1987 to evaluate A-E engineering performance.

5. Audit of Consulting Engineer in March 1988 to confirm the quality assurance program was acceptable.

6. Audit of A-E in March 1988 to ensure the quality assurance program was being implemented.

A-1 Revision 1

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7. Review of pipe whip restraint activities in May 1988 to confirm that pCE engineering activities were being properly performed.

8. Review of Non-Destructive Examination (NDE) contractor during 1988 Refueling Outage to ensure correct examination results.

9. Confirmation of whip restraint gaps during 1988 Refueling Outage to ensure gap measurements were correct.

10. Verification of A-E calculation inputs for whip restraints analyses.

During the performance of the above activities, QA and QC reviewed documentation, observed the performance of engineering and construction activities, verified equipment calibration and personnel qualifications, and evaluated the abilities and qualifications of various organizations to perform safety-related work. The evaluations were based on a technical assessment and a determination of the adequacy of the programs and the documentation for the programs. Where interfaces between several companies and organizations existed, QA reviewed their adequacy. Not only was the quality of the controls for the interfaces and activities assessed, but the quality of the work was also evaluated. Although deficiencies were observed and corrected, the activities associated with ,

pipe whip restraints were technically correct, based uren sound programs to ensure quality, and followed accepted industry practices and standards.

Nonconformance Reports (NCRs) have been written to document the deficiencies and corrective actions on all pipo whip restraints and the pressurizer surge line, plant heat-up will not be permitted until the QA Department has determined that both NCRs are dispositioned properly.

As was done for the Reactor Coolant Loop Thermal Expansion Test in 1986, QA personnel will review and observe performance of the inspection and monitoring programs developed for whip restraints and pressurizer surge line movements, respectively.

A-2 Revision 1 KOL/36950

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APPENDIX B DESCRIPTION OF PRESSURIZER SURGE LINE PIPING INTEGRITY ANALYSES B.O INTRODUCTION' This appendix provides a detailed description of the tasks performed to evaluate the piping integrity of the pressurizer surge line. The sections included in this appendix are:

• Overview of approach

• Piping analysis to evaluate root cause

+ Piping analysis to evaluate thermal expansion stresses

• Fatigue analysis of RCS and pressurizer nozzles

• Fatigue analysin of piping components

• Leak-before-break assessment B.1 OVERVIEW OF APPROACH The purpose of the piping integrity analysis of the surge line was to verify the credibility of the postulated root cause and to verify integrity of the surge line piping.

The steps required to perform the verification included piping analysis and fatigue evaluation. A nonlinaar piping analysis was performod to justify the root cause postulation of stratified flow effects. An elastic piping analysis was performed to evaluate thermal expansion stresses in the piping. Fatigue analysis was performed for the surgo line piping and the nozzles. Finally, a B-1 i

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1

. preliminary leak-before-break study was performed to demonstrate the inherent safety margin in the surge line.

B.2 PIPING ANALYSIS TO EVALUATE ROOT CAUSE A nonlinear piping analysis has been used to justify that thermal stratification was a probable cause of the observed surge line conditions. Based on observed data, it has been postulated that the pipe movement produced by thermal stratification is restrained by the whip restraints and resulted in a permanent upward set of the surge line. The nonlinear evaluation correlates these causes and effects.

The piping analysis was performed using a beam model of the piping

< system, which extends from the RCS hot leg nozzle to the pressurizer nozzle. The boundary conditions are assumed fixed at the terminal ends since the hot leg and pressurizer are much stiffer than the surge line. Thermal anchor motions are applied at these fixed points to model the effects of RCS and pressurizer movement. The nonlinear analysis was performed using the ANSYS (Reference 4) computer program with the following elements:

• STIF 20 - Elastic-plastic stre.ight pipe elements

• STIF 60 - Elastic-plastic curved pipe elements

• STIF 39 - Nonlinear gap elements The material stress-strain properties are input as bilinear curves in the nonlinear analysis. Curves were developed at 70* and 617*F.

The initial nonlinear analysis consisted of evaluating thermal stratification in the pipe using a temperature differential across the pipe section of 300*F. The temperature differential was applied as a linear gradient across the pipe section (420*F at top to 120*F on bottom) for the surge line horizontal length. The piping system B-2

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was initially assumed t.o be unrestrained. The results of the analysis showed that the surge line displacements are much larger than those predicted by the original design analysis which incorporates uniform temperature thermal expansion. Therefore, large interferences would exist at several pipe whip' restraints.

Pipe whip restraint gaps were included in the nonlinear enalysis, and the surge line was evaluated for several complete heat-up and cooldown cycles. A complete cycle consists of the following loadings:

Lower Upper Load Step No. Pipe Temp Pipe Temp Stratification AT 1 (heat-up) 120*F 120*F 0 2 120*F 320*F 200 3 120*F 345*F 225 4 120*F 370*F 250 5 120*F 395'F 275 6 120*F 420*F 300 7 350*F 450*F 100 8 550*F 600*F 50 9 (100% power) 615'F 615*F 0 10 (cooldown) 100*F 100*F 0 The evaluation also included gravity loading and thermal movements at the RCL and pressurizer nozzles.

The results of the evaluation showed that the surge line movements closed the gaps on several whip restraints. Due to plasticity during the heat-up cycles, the surge line moves above its initial position during cooldown. The general behavior of the surge line in this analysis correlates reasonably well with field observations of the line. Additional cycles were considered which indicatn that the surge line retains an upward set in the cold condition.

B-3

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B.3 PIPING ANALYSIS TO EVALUATE CODE COMPLIANCE l

Since the nonlinear analysis provides reasonable justification for  !

the observed motion of the surge line, the worst-case loading conditions were selected and an elastic analysis was performed for use in the qualification of the surge line. From the analysis, maximum bending stresses were obtained to verify compliance with the ASME Code (Reference 1) Equation 12 which limits thermal expansion stresses. The stratification effects are included in the load cases evaluated. A review of the surge line motion indicated that the maximum stresses resulted from restraint of the thermal expansion produced by the 300*F stratification effects. The maximum stroes was induced by providing a gap interference equivalent to the original gap interference plus the thickness of the added shims.

The results of the clastic piping analysis indicate that the thermal expansion stresses are less than the expansion stress limit of code Equation 12. The remaining ASME qualification is described in Sections B.4 and B.S.

l B.4 FATIGUE ANALYSIS OF RCS AND PRESSURIZER NOZZLES '

This section summarizes the ASME Code (Reference 1) fatigue .

evaluation of the pressurizer surge line nozzle-to-hot leg and nozzle-to-pressurizer. This analysis lacluded consideration of the potential effects of thermal stratiffe.ation and whip restraint gap closure as well as design transients. The pressurizer nozzle, which is not significantly affected by stratification, was evalunted by load conformance and qualified. The results of the fatigue calculations of the RCS nozzle indicate that ASME Code limits are satisfied for at least 40 heat-up and cooldown cycles, as well as other design transients. The plant has currer.tly completed 32 heat-up and cooldown cycles. Data from the plant heat-up monitoring program will be used to confirm this analysis and to B-4

determine accurate stresses and cycles for longer term fatiguo calculations.

B.4.1 Thermal Stratification Stresses Thermal stratification in the pressurizer surge line causes additional stresses at the reactor coolant loop branch nozzle. These stressos result primarily from the interaction between the thermal movements of the line, and the restraint of that movement by the closure of gaps at the pipe whip restraints. Several piping analyses with various stratification profiles and gap closure conditions were used to obtain maximum loadings at the nozzle location.

The branch nozzle stresses were obtained from these loadings, using the data provided in the WRC Bulletin 297 (Reference 2) to obtain maximum stress components in the nozzle. These stresses were combined with stresses from the thermal transient analysis. The stresses from the reactor coolant c

pipe loadings (run nide) were calculated using ASME -

Section III methodology and stress indices.

The results from these calculations were factored into the usage f actor determination as described in Section B.4.3.

i B.4.2 lbermal Transient Stresses The ctresses for thermal transient loadings were obtained .

from finite element analyses of the reactor loop nozzle.

Transient loadings were applied as defined in Westinghouse System Standard 1.3K (Referenco 3). This document provides conservativo design estimates of maximum possibic transient loadings and number of occurrences of thc,o transients. This document, which had not been developed at the time of the original Trojan design analysis, is conridored to contain a  :

B-5

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o' more realistic transient description for the RCL surge nozzle and, therefore, was used for this analysis.

Two types of nozzle configurations were considered, one with a thermal sleeve, and one without. The thermal sleeve was removed from the surge line nozzle in 1982 due to cracking of the attachment wolds. All transients which occurred after this tlwe were evaluated for the nozzle without a thermal sleeve. The number of transient cycles was determined based on the number of heat-ups ar.d cooldowns and the actual years of operation assuming design transients occurred at the rate provided in the Westinghousa System Standard 1.3K.

Based on realistic frequencies of occurrence, this approach generally results in a very conservative estimate of the number of transient cycles.

Peak and secondary stresses were combined with the stresses resulting from stratification in the surge line to obtain a total thermal stress.

B.A.3 Fatigue Usage Factor Fatigue usage factor was calculated for the RCS nozzio using ASME Code Section III techniques and the design fatigue curve '

for austenitic stainless oteol. To maximize plant operating flexibility, the number of heat-up/cooldown cycles and the ,

stratification temperature difference was maximized until a usage f actor just below 1.0 was achieved. ,

B.5 FATIGUE ANALYSIS OF PIPING COHPONENTS A fatigue analysis of the critical piping components evaluated the potential effects of stratification and standard design transients.

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A bounding analysis was performed on all girth butt welds by developing an enveloping stratification stress.

Based on a three-dimensional finite element analysis..a temperature profile was selected which maximized the stratification stresses.

Stresses from other loading (normal thermal expansion, pressure, seismic, and thermal transients) were considered by comparison with generic fatiguo calculations of this line.

The three-dimensional stratification model was ccnstrained to prohibit any free rotation, which simulated the worst case constraints which could have actually occurred at Trojan from contact with whip restraints. Therefore, enveloping stratification i stresses could be obtained without using the stratification piping analysis (Section B.2).

The usage factor was calculated based on ASME Section III methods, including the design fatigue curve. This analysis demonstrated that usage factor limits could be met for approximately 40 heat-up and cooldown cycles as compared to the 32 eurrently cor.pleted.

i B.6 LEAK-BEFORE-BREAK ASSEOSMENT A preliminary leak-before-break assese.ent of the surge line piping has been completed. This assessmeat demonstrates that a flaw in Lt.o surge line would not propagate to leakage in the near term. A preliminary assessmert was completed which demonstrated that a 0.25T (wall thickness flaw) would require approximately 100,000 cycles to propagate to a 0.75T-size flaw which would still be stable under all loadings. The frequency of significant stratification cycles is low enough that many additional years of continued operation could be justified.

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e' In addition, it is judged that leak-befort.-break can be demonstrated with the recommended margins (margin of 10 with' respect to leak detection capability, margin of 2 on flav size, and margin of 1.4 on loads).

REFERENCES

1. ASME Code,Section III, Division 1, Subsection NB.

2. WRC Bulletin 297, "Local Stresses In Cylindrical Shells Due to External Loadings On Nozzle - Supplement to WRC Bulletin 107",

Revision 1 September 198.

3. Westinghouse System Standard 1.3X, Revision 0, 1979 (Westinghouse Proprietary).

4. ANSYS Computer Program, Rev. 4.2.b, Swanson Analysis System, Inc.

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