ML101690170

Enclosure 5, Prairie Island Nuclear Generating Plant, Units 1 and 2, Supporting Engineering Evaluations, EC 16270, Screening of Pipe Whip Interactions for Sdp

ML101690170
Person / Time
Site:	Prairie Island
Issue date:	06/11/2010
From:	Northern States Power Co, Xcel Energy
To:	Office of Nuclear Reactor Regulation
References
EA-01-070, IR-10-010, L-PI-10-060 EC 16270
Download: ML101690170 (52)

Text

ENCLOSURE 5 PRAIRIE ISLAND NUCLEAR GENERATING PLANT SUPPORTING ENGINEERING EVALAUTIONS EC 16270 51 Pages Follow

Xcel Erergy" EC-0441 EC Closeout Package Report (Rev. 3)

Report Date: 06/11V2010 EC Number: 0000016270 Revision: 000 Engineering Change EC Number :

0000016270 000 Facility PI Status/Date :

CLOSED 06/10/2010 Type/Sub-type :

EVAL /

EC

Title:

SCREENING OF PIPE WHIP INTERACTIONS FOR SDP Mod Nbr:

KWI KW2:

KW3:

KW4:

KW5:

Master EC Work Group Temporary Outage Alert Group

E-ME/CS DE Aprd Req. Dt.

06/30/2010 WO Required

N Image Addr Exp Insvc Date Adv Wk Appvd Alt Ref.

Expires On Auto-Advance Priority Auto-Asbuild Caveat Outst Resp Engr

PTTD06 Units and Systems Facility Unit System

System Description

PI 0

OTH OTHER Attributes Attribute Name Value SCRN NO NA SIMULATOR SYSTEM HEALTH EVAL NO PORC DTE PRIORITY RANKING Pedigree Information Updated By PTTD06 Last Updated 06/02/2010 Notes This eval does not support design basis. Used as input into SDP. No 50.59 s creening. required.

Page 1 of 3

C40XcelEnergy" EC-0441 EC Closeout Package Report (Rev. 3)

Report Date: 06/1112010 Topic Notes Se Sarpon DESCRIPTION JUSTIFICATION REVIEWER COMMENTS Notes See sharepoint purpose section.

See Sharepoint See QF0628 in S'karepoint.

Cross References XRef Number Sub Status Date Reference Description AR 01178236 APPROVED 04/15/2009 No HELB flooding calculation for Turbine Building Affected Documents Milestone Milestone Date ID Name Req By APPROVED BY 06/10/2010 BRSM05 Brossart, Mark A APPROVED Notes: Preparerand Reviewer were Verified to be qualified to perform the evaluation. Assumptions are validated and the evaluation is reasonable using sound engineering principles. The vendor eval captured in EC 16275 was received and approved (Ref 6).

EC is approved.

CLOSE 06/10/2010 LDWHIP01 Whipple, Linda D CLOSED Notes:

PRE JOB BRIEF 05/05/2010 PTTD06 Potter, David J Notes:

PREPARED (EVL) 06/02/2010 PTTD06 Potter, David J H/APPR

Notes, TECHNICAL RVW 06/10/2010 N153792 Slack, Brian C Notes:

Document References Facilty Doc-Type PI EC Sub-Type Doc #

0000016270 Sheet Rev 000 Minor Rev Date 06/10/2010 Pedigree Information Page 2 of 3

XcelEnergy-EC-0441 EC Closeout Package Report (Rev. 3)

Report Date: 06/11/2010 Pedigree Information Page 3 of 3.

QF-0528 (FP-E-MOD-07) Rev. 1 She~et

1

,of

.3 DOCUMENT NUMBER/ TITLE':

EC162701I Screening of Pipe Whip, Interactionsfor SDP, REVISION:

N/A DATE:

6/02/10.,

ITEM REVIEWER'S COMMENTS, PREPARER'S REVIEWER'S RESOLUTION DISPOSITION f Provide-the basisithat 4" pipe break = 5000 Added Assumptions section and an ok gpm in the acceptance criteria.

assumption.

2 Element I basis: Additional areas beyond the Revised text to, not limit the criteria ok 15FW heater were included. Add those toareasaround 15 FW heaters areas to the technical justification.

3 Element 2 basis: The HELB criteria is "200F Corrected text ok and greater-and greater than 275psig" 4

Element3 basis: Provide refe rences.for the Added assumptions and basis.

ok statements regarding the severity of-a 5000 gpm flow.

5 Element 5 basis: I counted different numbers Counting' corected Ok of tests for each category in the NUREG. 4, 17, and 11 for moving pipe thinner, equal wall, and moving pipe thicker, respectively.

I'could notvalidate'the'inputs:or results of the.

LS-DYNA analysis as It is not complete: This will need to be*Validated prior to.completion

,of thisEC.

6 Element 6 basis: I found differentnomihal Values ih'tables are gauge pressure ok system pressures for.CD and MS on the heat rather~than absolute. Values were, balanc, diagrams (444.7 psia &..841.,7 p'sia).

changed to be,conshstant"with 560%

depending on unit and power level. I could power on unit-2 Which maximizes not validate HD pressure from the heat pressures.

balance diagram.

In the pipe flailing calculations, I think the end Corrected.

conditions for the column should result in C=2 instead of C=1.

I could not validate the neoprene mechanical Changed to Hypalon due to properties in MERM.

-availability ofdata.

Thestress calculations for the columns Corrected.

should include the C = 2,end'condition, AlIthough not the: purpose o' the flailing. pipe Added additional tablesithat calculations, the results given show that the indicated that for a slenderness 25 ft long steel column will buckle under the ratio of 806, the pressures needed to jet load described earlier. I believe a cause buckling exceed pressures discussion stating that this is an seen In'the plant systems, unrealistically long unsupported length ýis warranted to: eliminate this potential comment by. readers.

7 Element 1 implementation: lIdon't think that Agreed. Corrected..,

ok Page, 1 of 3

Error! Reference source not found.

Error! Reference source not found., Revision Error! Reference source not found.

interaction #39a should be excluded. There was no mention of it in. the SDP report flooding tables.

8 Element2 implementation: Item. 7 should not Agreed. Text Adjusted.

ok be excluded. It is high energy per ENG-ME-358.

9 Element 4 implementation: The"CS" field in Changed references to tech ok passport used as a reference in several manuals as. appropriate.

locationsis an uncontrolled field. A better reference should be given If possible. It Was noted that VTM XH-1 95-22 is. applicable to several of these valves and could potentially provide a better reference,

,Interaction 14: Valve CW-32-1 is present on Added'text for interaction 14.and the 14"line to the H2 coolers. This valve 114.

could See a significant bending moment if.the 16" line were-displaced. It should be discussed.

Interaction 114' Valve 20L-32-1 is present on the 14" line to theH2 coolers. This Valve.

could see a significant bending moment if the 16" line were displaced. It should be discussed.

10 Element5 implemeritation: Interaction 20a Text Adjusted ok was screened for cast iron and meets the thickness criteria. It should be excluded from the SDP.

The discussion,,related to Interaction 151 interaction 151 failed the LS-Dyna failing the LS-DYNA work can not be analysis, Included. forcompleteness validated.

but screened out due to geometry.

11 Remaining interactions:

-20a now excluded in element 5 ok

-20a should bIe included'here unless excluded in element 5

-29 & 30were screened out and should be

-29&30- Agreed,. Text Adjusted.

removed.

-143 was screened out due to 4'

-143-Agreed. Text Adjusted.

-197-199 were screened"out in attachment A

-197 remains in, 198 &199

-200 & 201,should remain in the SDP removed.

-200 &201 kept in and not screened out.

12

==

Conclusion:==

Re-check the total numbers of Numbers updated.

Ok interactionsexciUded. I got'different numbers and 'the comments here will likely change a few.

13 Attachments' I think Att B can be deleted, or Attachment B deleted.

ok at least changed to the SDP report.

14 Att A, #53: The interaction is not shown on Drawing number corrected.

ok drawing A45..

15 Att A, #76: A discussion is needed regarding Added Text to this section ok a break at the west 900 elbow that pushes the pipe horizontally towards the vertical riser.

16 Att A, #82: A break in the vertical portion of Added Text.

ok

Error! Reference source not found.

Error! Reference source not found., Revision Error! Reference source not found.

16-FW-3 is also possible but hot discussed.

It is noted that this break does* not-appear to affect the resultS.

17 AttA, #151: I dbn't qUite follow the discussion Text Adjusted ok of this break. T11e.20" line is a:straight northý south line With no elbows. Breaks would need to be in the branch conhections to cause pipe whip, Which would, be, adifferent interaction.

18 Att.A, #159: The discussion references. an Added sketch and adjusted text..

ok isometric that is not included.

The discussion states that the northernmost FW heater is applicable, but that piping is in a different grid reference and' has no chance, of Interacting.

19 Att A, #180: The interaction is not shown on Adjusted drawing number and ok drawing A48 added text to clarify.

The 12" MS line goes from vertical to horizontal at -725' elevation. This.wiil cause a pipe Whip, although not towards the ZX line.

Add: discussion as'needed.

20 Att A, #197-: It is not clear that the breaki interaction cannot be excluded.

ok between 71&5V6 and 717' is acceptable based Removed from appendix.

on the,.discussion, Clarify as needed.

Ibelleve that a sketch should be added to illustrate thedimiensions and relative positions stated in this interaction.

21 Att A, #198::1 believe that a sketch should be Added Sketch, ok added to illustrate the dimensions and

_relative positions stated in this interaction.

Reviewer: Brian Slack Date: 6/05/10 Preparer:

&'/1,

,*/DateO L/4/6 1,;9",rzrW

/

r

EC 16270 Page 1 of 38 SCREENING OF PIPE WHIP INTERACTIONS FOR Prepared By: DJP SDP Date: 06/02/2010 P u rp o s e...................................................................................................

..... 2 M e th o d o lo g y.................................................................................................

.. 2 A cceptance C riteria.......................................................................................

2 Inherent C onservatism...................................................................................

2 A n a ly s is....................................................................................................

.... 5 Screening Flow Chart.................................................................................

5 Element 1: Was the target included in Previous CC HELB SDP?........... 6 Element 2: Is moving pipe normally isolated?..........................................

6 Element 3: Is target pipe so small that it does not contribute to the SDP (4 ")?.....................................................................................................

..... 7 Element 4: Does the target pipe have cast iron component that could fail? '.........................................

........... 7 Element 5: Is the moving pipe thicker than the target pipe?..........

8 Element 6: Did ENG-ME-732 determine interaction could not occur due to g e o m e try ?................................................................................................

.. 9 Flowchart Implementation......................................................................

20 C o n c lu s io n s...............................................................................................

.. 24 R e fe re n c es...................................................................................................

.. 2 6 A tta c h m e nts..............................................................................................

26 A tta c h m e nt A...............................................................................................

.. 2 7

EC 16270 Page 2 of 38 SCREENING OF PIPE WHIP INTERACTIONS FOR Prepared By: DJP SDP Date: 06/02/2010 Purpose The purpose of this evaluation is to provide a better understanding of the interactions associated with HELB. As part of the plant design basis assumptions, HELBs are required to be assumed as well as their direct consequence. If the assumed HELB is a circumferential break, pipe whip is an expected consequence. The targets that could result include other sources of water. This evaluation will review the possible interactions to determine if significant damage to the target piping is a reasonable event.

It should be noted that this evaluation is not to conclude that interactions do not exist. Rather, the intent of this evaluation is to lay out criteria associated with reviewing the circumferential break interactions and show which interactions are not expected or will result in neglible consequences.

Methodology This evaluation will develop screening criteria to be applied to the high energy line interactions.

The screening criteria is in the form of a flow chart. Each step of the flow chart will be justified on its own accord to determine its appropriateness. The justification will use engineering judgment and technical references.

After the establishment of the flow chart, the flow chart will be applied to the interactions listed in ENG-ME-732 [2].

Acceptance Criteria It should be noted that while this evaluation will "screen out" HELB interactions, screening out merely establishes that damage to the target piping is "minimal".

It has been determined that pipe break flow rates less than 5,000 gpm do not result in significant consequences. 5,000 gpm is greater than the flow that would be expected from a complete guillotine break of a 4" line from the CL system (See Assumption 1). A four inch line has an approximate flow area of 12.5 square inches.

Piping "screened out" by this evaluation merely means that in the unlikely event the screened out interaction occurs the target pipe will not be so great as to exceed a 12.5 square inch opening area.

Inherent Conservatism This analysis has some inherent conservatism built in that should be acknowledged.

Thrust forces-This analysis assumes that reaction forces from a break location are sufficient to cause pipe bending. Not all breaks are capable of generating significant reaction forces. This analysis does not calculate the reaction forces from a break location to determine if sufficient force is generated to cause whipping. Rather, it is assumed that if a break occurs, it generates sufficiently high forces to cause pipe whip.

Moment Arm-This evaluation assumes that the break location, direction of the jet and hinge point are conducive to generation of pipe whip. This evaluation contains examples of moment arms needed to cause plastic elbow deformation. In the context it was used, this evaluation demonstrated a moment arm of finite length in order to cause pipe whip.

That length of moment arm required is dependant on the assumed loads, direction of jet, and pipe diameter and size. Detailed hinge location calculations were not performed and this evaluation assumed that a sufficiently long moment arm is available associated with the force being applied.

EC 16270 Page 3 of 38 SCREENING OF PIPE WHIP INTERACTIONS FOR Prepared By: DJP SDP Date: 06/02/2010 Kinetic energy-This evaluation assumes sufficient kinetic energy is developed in the moving pipe to cause damage in the target pipe. Kinetic energy is equal to the work applied from the jet force. Work is determined by multiplying the applied force by the distance the force acts. However, the work to create the plastic hinge must be subtracted from the kinetic energy. In several cases of field application, the distance between the whipping pipe and the target pipe is very small (i.e. inches). NUREG CR-3231[3]

estimates that travel distances must be greater 3 pipe diameters of the moving pipe in order to develop sufficient kinetic energy.

Energy transfer-For the interactions that are not excluded, it is assumed that sufficient kinetic energy is transferred from the moving pipe to the target pipe to cause failure of the impacted pipe. In a perfectly inelastic collision, the velocity of both objects are equal following the impact (consider two balls of clay colliding). This assumption is close to reality when the two pipe collide orthogonally with sufficient energy. However, in reality, until plastic deformation occurs in both the moving pipe and the target pipe, the collision will be elastic. As the impact angle between the swinging pipe and the target pipe approaches zero, the impact behaves more elastically. Additionally, the impact area is spread over a larger area of the target pipe. Because the targets are generally made of ductile steel, extending the impact zone results in a lower magnitude of deformation but the deformation occurring over a larger area. This is illustrated in the diagram below.

Vi 4V As can be seen, as the approach angle approaches zero, the length of contact on the target line is extended. As the impact length is extended, the same energy imparted into the target pipe results in deformation of smaller magnitude.

Additionally, the main cause of deformation of the target piping is the absorption of kinetic energy. The effective impact velocity changes as the approach angle changes.

Therefore, if the moving pipe was moving towards the target pipe where angle" A" is zero (an orthogonal impact). The following is the resulting velocity toward the target pipe.

EC 16270 Page 4 of 38 SCREENING OF PIPE WHIP INTERACTIONS FOR Prepared By: DJP SDP Date: 06/02/2010 VY = Cos(A)

• V = Cos(O)

• V = V Next consider the case where the angle "A" is 45 degrees.

VY = Cos(A)

• V = Cos(45)* V = 0.707* V Graphically, the relation ship between Cos (A) (which is proportional to Vy) and Angle "A" 1.2 0.8 0.6-.

0.4 0.2 0 i 0

10 20 30 40 50 Angle "A" 60 70 80 90 100 Therefore, it can be seen as the approach angle decreases, the impact velocity decreases for a fixed moving velocity.

Additionally, many of the interactions in the field are not between pipe that are perpendicular skew. Many of the HELB/target pipe combinations are parallel. Where the pipes are parallel, the worst case interaction geometry would be as follows:

V V

Again, the impact energy is extended over a much longer length of the target piping. As the length of target piping impacted is extended, the amount of energy needed to deform

EC 16270 Page 5 of 38 SCREENING OF PIPE WHIP INTERACTIONS FOR Prepared By: DJP SDP Date: 06/02/2010 the target piping increases and permanent, substantial deformation or pressure boundary failure is less likely.

Assumptions

1.

Piping less than 4" sch 40 NPS can be excluded from the analysis-The risks associated with a flood are associated with the time to isolate the event. As the allowable operator response time increases, the probability of success increases.

Due to the large volume of the condenser pit and large area of the turbine hall, the time to reach critical flooding heights in the pre-April configuration is three hours with flow rates less than 5,000 gpm [211. Although the probability of success is not 100% for a required isolation times greater than 3 hours3.472222e-5 days <br />8.333333e-4 hours <br />4.960317e-6 weeks <br />1.1415e-6 months <br />, the success rate is high enough that judgment amongst personnel involved with this project indicate low flow events from pipes less than 4" will not be a significant contributor: This is an assumption that will be validated by later work associated with the SDP. EC 16090 [24] concludes that a 4" CL line break will result in 2911 gpm. Therefore, it can be seen that excluding target pipes less than 4" sch 40 NPS will result in required isolation times of approximately 3 hours3.472222e-5 days <br />8.333333e-4 hours <br />4.960317e-6 weeks <br />1.1415e-6 months <br />.

2.

Nominal wall thicknesses were assumed for both the moving pipe and the target pipe.- It is acknowledged that the target piping is subject to corrosion as it has been in service for several years. However inspection results (and engineering experience) indicates that nominal pipe wall thickness are suitable for this type of evaluation. The basis for using nominal wall thickness is based upon the experience that piping is typically manufactured at thicknesses greater than the nominal thickness for the pipe size and schedule. In fact, much of the service water piping system (even after 30 years of service) is greater than nominal thickness for the piping's diameter and schedule. Additionally, available industry guidance indicates that general corrosion (general uniform wall attack rather than localized wall attack such as Microbiologically Induced Corrosion) general corrosion rates of 1 mil per year [20]. The experience at PINGP is that general corrosion rate are less than 1 mil per year. Localized pipe wall thinning (areas of thinning approximately 1-2" in diameter) on 14, 16 and 24 NPS pipe represents a small fraction of the pipe's circumference (between approximatelyl % and 5% of the pipe circumference). Therefore, considering wall thickness equal to nominal is a reasonable estimate of wall thickness for a structural assessment.

Analysis Screening Flow Chart Below is the flow chart associated with screening.

EC 16270 Page 6 of 38 SCREENING OF PIPE WHIP INTERACTIONS FOR Prepared By: DJP SDP Date: 06/02/2010 11 Has the interaction been evaluated in CCHELB SDP?

-*.L**xcluded from this SDP No &

21 Is moving pipe normally isolated/

Denerpized?

3 NO+

F Is the target less than 4" NPS?

No I, Does the target have a cast iron Component that could fail?

~Exclude from SDP

_Pý Will not contribute Significantly, does not Warrant further investigation In this EC N4~

Is moving pipe thicker than target pipe?

Yes No AES analysis Supports no 01 Target damage, Excluded from interaction set 5

t-Has the interaction been geometrically analyzed and concludes target pipe damage is minimal?

yes No Can not conclude target pipe receives minimal damage Not Considered a piping interaction.

Excluded The application and justification of each of the flow chart elements are discussed below.

Element 1: Was the target included in Previous CC HELB SDP?

This screening step considers whether the flooding affects have been previously assessed by the NRC.

Technical Justification In CC HELB, high energy line breaks were assumed to affect the CC piping in Unit 1 and 2 of the TB. In addition to failure of the component cooling water line as a result of this postulated break location, significant flooding flows were postulated from the cooling water system. These effects were accounted for in the assessment of the "CC/HELB" finding.

Justification of Order This criteria is non-subjective and simple to implement.

Element 2: Is moving pipe normally isolated?

This screening step considers whether the target pipe is normally de-energized. The licensing basis for Prairie Island requires the High Energy Line Break program to include piping systems for analysis if the piping is meets the HELB criteria of 200F operating temperature and greater and

EC 16270 Page 7 of 38 SCREENING OF PIPE WHIP INTERACTIONS FOR Prepared By: DJP SDP Date: 06/02/2010 greater than 275 psig design pressure. Branch technical position MEB 3-1 [4] relaxes the guidance indicating that piping need not be considered high energy if the duration of time that it is high energy is less than 2% of the operating cycle.

Technical Justification From a PRA perspective, application of the 2% guidance reduces the initiating event frequency to 1/5 0 th and from a PRA purist standpoint should still remain in the SDP but at a lower initiating event frequency. However, the lines that meet this criteria are in service much less than 2% of the plant normal operating cycle. In actuality, these lines are associated with plant start up conditions where the plant is only in this configuration for a day (or so) a year (approximately 0.3% of plant planned operation) or during transients such as condenser steam dump.

Justification of Order This criteria is non-subjective and simple to implement. References are readily available (ENG-ME-732 Rev 1 [2] and ENG-ME-358 [5])

Element 3: Is target pipe so small that it does not contribute to the SDP (4")?

This screening step will consider the target pipe diameter. Targets less than 4" NPS are excluded from further examination.

Technical Justification See Assumption for discussion.

Justification of Order The element was chosen second. Assuming that 4" piping does not meet any of the later screening criteria, PRA personnel indicate that the lower flow rates will be screened out regardless. Following steps require additional work including field intensive walk downs.

Therefore, placement of this criteria eliminates the need for further walk downs because the results of those walk downs are irrelevant. The flow is not sufficient to be a significant contributor.

Element 4: Does the target pipe have cast iron component that could fail?

This step will consider whether the target piping system has cast iron components. If it is determined that the target piping system has cast iron, then the interaction bypasses element 5.

Technical Justification Many of the target piping systems have cast iron components. These components are items such as valve bodies, tee, reducers, et cetera. While cast iron is an engineering material with decent strength characteristics, it tends to be brittle in nature. Brittle materials will not yield greatly before breaking. Should the target piping systems have contact with a whipping pipe, the target system is more vulnerable if a cast iron component is in the load path generated by the piping interaction. If the cast iron component is near an anchor point (sufficiently larger pipe or restraint) or is at or near the location of the plastic hinge, then the cast iron piping is more likely to have a large rupture instead of small leakage crack. If the material of construction (valve, etc) what not known, it was assumed that the piping system had cast iron components.

Justification of Order The element was placed prior to elements that rely on the ductile properties of steel.

The implications are that pipes with cast iron components are screened in to catastrophically fail even if a 2" steam line makes contact with a 16" heavy wall pipe with a cast iron valve 10' from the interaction point. This is very conservative for smaller whipping pipes but included due to uncertainty.

Element 5: Is the moving pipe thicker than the target pipe?

This element will compare the wall thickness of the target pipe versus that of the moving pipe.

Only target pipes that are thinner than the moving pipe (regardless of pipe diameter) are considered vulnerable.

Technical Justification Justification for this element is associated with field tests documented in NRC NUREG CR-3231

[31 and supporting computer simulations modeling piping interactions [6]..

CR-3231 [3] provides guidance associated with pipe wall thickness screening. The report concludes that the probability of failure was considered high if the moving pipe was thicker than the target pipe. Review of test results indicate the following:

Category Number of Tests Number of Failures Moving pipe wall 4

0 thinner than target wall Moving pipe wall 17 3

equal to target wall Moving pipe wall 11 5

thicker than target wall Total tests 32 8

In summary, no failures occurred when the moving pipe wall was thinner than the target pipe wall.

Three failures out'of 17 trials occurred when the pipe wall thicknesses were equal. Five failures out of eleven trials occurred when the moving wall thickness was greater than the target wall thickness. Failure criteria in CR-3231 [3] was any loss of pressure retaining function of the target piping. As discussed in the acceptance criteria section, the failure criteria of this evaluation is associated creating with large flow areas in the target piping. None of the failures in CR-3231 met the criteria of failure established by this evaluation.

As further validation of this screening criteria, a contractor performed simulations of selected cases using the LS-Dyna software package under EC 16275 [6]. LS-DYNA is an advanced general-purpose multiphysics simulation software package that is actively developed by the Livermore Software Technology Corporation (LSTC). While the package continues to contain more and more possibilities for the calculation of many complex, real world problems, its origins and core-competency lie in highly nonlinear transient dynamic finite element analysis (FEA) using explicit time integration. LS-DYNA is being used by the automobile, aerospace, construction, military, manufacturing, and bioengineering industries.

EC 16270 Page 9 of 38 SCREENING OF PIPE WHIP INTERACTIONS FOR Prepared By: DJP SDP Date: 06/02/2010 The computer simulation modeling utilized plant specific diameter size and thickness criteria from HELB interactions. The following is a list of possible piping combinations that were considered.

[Ref 2]. (This list was developed by completing the screening criteria later in this evaluation and utilizing only those where the moving pipe wall thickness was not greater than the target pipe thickness.)

I Moving Pipe Target Diameter 8

2.5 6

12 16 20 8

Pipe Diameter Schedule/

40/

80/

80/

Std/

30/

20/

80/

Nominal 0.322" 0.276 0.432" 0.375" 0.375" 0.375" 0.500" Wall Thickness 24 20/ 0.375" x

x x

14 XS/0.500 x

x x

x x

16.

30/0.375" x

x x

Bounding scenarios were selected from the above interaction matrix. The demonstration of which cases were bounding were demonstrated using engineering techniques. If it was determined that an interaction combination could not be bounded by a simplified engineering analysis, then the specific interaction was evaluated. Because this evaluation was used as a screening criteria, an orthogonal configuration for pipe contact was selected as it represents the limiting case. Nominal pipe wall thickness were utilized based upon assumption 2.

Justification of Order At this point in the screening criteria, only interactions comprised of carbon steel are included (due to element 4). The information needed to determine whether these interactions are screened out based upon this criteria is readily available in ENG-ME-732 [2].

Element 6: Has the interaction been geometrically analyzed and concludes target pipe damage is minimal?

This screening step determines if the geometry of the interaction is conducive to significant piping failure. It reviews data within ENG-ME-732 to determine if the interaction is a realistic event.

Technical Justification There are several components needed for pipe whip to occur:

1. A complete guillotine break must occur.

2.

Plastic hinge must form in the piping.

In ENG-ME-732 [2] both of these elements are assumed to occur on the base list. ENG-ME-732

[2] established the list of interactions in attachment one based upon proximity. Once the list was established, the interactions were evaluated. These are conservative assumptions to establish the interaction list. In order for a plastic hinge to occur additional items are required. From engineering statics, the moment developed at any one point is defined the cross product of two vectors. In the case of pipe whip the vectors are defined as the force vector from the jet and the displacement vector from the jet location to the plastic hinge.

It takes a sufficient bendingmoment to cause deformation of a pipe. The table below demonstrates total moments needed to cause stresses in excess of the yield stress in a schedule 40 pipe. (Pipe wall thickness taken from Mechanical Engineering Reference Manual [7]). The full

EC 16270 Page 10 of 38 SCREENING OF PIPE WHIP INTERACTIONS FOR Prepared By: DJP SDP Date: 06/02/2010 mathematical computation will be written for a 5" schedule 40 pipe to demonstrate the methods used to develop the table.

Solid _ Rod: Ix = )--r4 4

7' 4

7)T 4

(D

)

Pipe:Ix

- r0 D r1D KD

_DID 7

_(OD_

(L--2 )

2

- D OD - Tj4

= 7c r

( 5

.5-6 3 " 44_ ( 5.5 6 3 " "

)

Pipe,

=3

-0.258

=15.16In4 4.,

2 2

Mc (Orb,max )Ix

-bmax

- or _ M -

(

c Dis tan ce _ From _ Neutral _ Axis = ROD = 5.563"/2 = 2.7815" M = 43KSI(yeild _ Strength _ for 1020 Steel[7]

M - (('bmax)1x,

(43,000 PSI)15.16In4 = 234,000_ In - lbf C

2.7815" Pipe Sch OD (in)

T (in)

Ix (INA4)

Syt Required Moment NPS

[7]

[7]

(PSI) [7]

(Inch-lbs) 2 40 2.375 0.154 0.67 43000 24,000 3

40 3.500 0.216 3.02 43000 74,000 4

40 4.500 0.237 7.23 43000 138,000 5

40 5.563 0.258 15.16 43000 234,000 6

40 6.625 0.280 28.14 43000 365,000 8

40 8.625 0.322 72.49 43000 722,000 10 40 10.750 0.365 160.73 43000 1,280,000 12 40 12.750 0.406 300.21 43000 2,020,000 14 40 14.000 0.437 428.61 43000 2,630,000 16 40 16.000 0.500 731.94 43000 3,930,000 20

.40 20.000 0.593 1703.71 53000 7,330,000 It should be noted that the force calculated above is based upon yield strength which is conservative. The yield strength is determined by a 0.2% parallel offset from the proportionality limit of the stress strain curve. In the application of pipe collapse and bending, deformation well beyond 0.2% is needed and significant work hardening may be occurring while the pipe is collapsing. The pipe deforming in shape and the material work hardening are counteracting affects, but using the yield strength is conservative in this application.

As can be seen from the table above, some very significant moments need be applied in order to cause deformation of the pipe section with a yield stress of 43 ksi. Assuming a jet force is applied perpendicular to the moment arm, the required length of the moment can be determined. For this example, a jet force is determined as follows (based upon ENG-ME-369 [8]).

EC 16270 F

Page 11 of 38 SCREENING OF PIPE WHIP INTERACTIONS FOR Prepared By: DJP SDP Date: 06/02/2010 Thrust = P*A*K = (920psia-14.7psia)*20.01*1.26 = 22,825 lbf L - Moment _ 234,000_ in - lbf _ 10.25 Thrust 22825 lbf The pressure 920 psi is selected based upon heat balance diagrams and is the highest pressure in either unit 1 [9] or unit 2 [10] (pressures downstream of feedwater pumps).

Pipe Sch Pipe Flow Area Required Moment Thrust Load (1.26 x pipe Moment NPS (Inches2) [7]

(Inch-lbs) flow AREA'*(920-14.7)

Arm psi)

Length (in) 2 40 3.356 24,000 3,828 6.27 3

40 7.393 74,000 8,433 8.78 4

40 12.73 138,000 14,521 9.50 5

40 20.01 234,000 22,825 10.25 6

40 28.89 365,000 32,954 11.08 8

40 50.03 722,000 57,068 12.65 10 40 78.85 1,280,000 89,942 14.23 12 40 111.93 2,020,000 127,676 15.82 14 40 135.32 2,630,000 154,356 17.04 16 40 176.72 3,930,000 201,581 19.50 20 40 278.00 7,330,000 317,108 23.12 Therefore, it can be seen that even with the largest thrust loads available, a significant moment arm must be present to allow the piping to deform. If the forces act through the plastic hinge, then no whipping will occur. Applying discharge pressures from other systems (main steam, condensate, heater drain) would result the following moment arm increases from above(limiting pressure observed in [16]):

System Nominal Previously Percent of Percent Increase Operating assessed evaluated in moment arm Pressure (PSIG)

Pressure (psig) pressure length Heater Drain 685 ([11] for pipe 905.3 75%

32%

8-HD-6)

Condensate 430 [16]

905.3 47.5%

110%

Main Steam 827[16]

905.3 91.4%

9.4%

In order for a whip to occur a plastic hinge must be formed in the piping system. As previously discussed, significant moments must be generated in order to cause a bending point. Assuming the piping system is of consistent geometric characteristics (area moment of inertia in particular),

bending will first occur at the point where the greatest moment is created between anchors.

Secondary plastic hinges may be formed after the first hinge allows maximum displacement of the whipping pipe. However, it should also be noted that when plastic hinges are formed the hinging section of pipe is collapsing. The collapsing of the pipe will tend to reduce the net allowable flow area and only the remaining kinetic energy will remain to form the secondary hinge. Second, the forces required to cause a pipe whip are beyond the systems normal flow capability, the large forces are caused by rapid expansion of a subcooled liquid flashing to equilibrium conditions. These events occur rapidly such that the initial hinge is capable of forming but secondary hinges do not form.

In practical application, the motion of pipe whip can be demonstrated and applied. The following are geometric configurations which are common in the plants piping configurations.

EC 16270 Page 12 of 38 SCREENING OF PIPE WHIP INTERACTIONS FOR Prepared By: DJP SDP Date: 06/02/2010 Anchor A

Front View Isometric A x I B

A B

Top View Side view Figure 1 In the figure above, pipe "A" is the target pipe and the pipe "B" is the whipping pipe. It should be noted that if the target pipe is parallel with the plane defined by the plastic hinge and the force vector (jet from the end of the broken pipe) then contact will not occur. This case is outlined above in figure 1. This can be seen by severing the line in the horizontal section of line B and forming the plastic hinge at either anchor location.

EC 16270 Page 13 of 38 SCREENING OF PIPE WHIP INTERACTIONS FOR Prepared By: DJP SDP Date: 06/02/2010 A-Anchor A

B Front View Isometric BB A

A X

Top View Side view Figure 2 In the figure above, pipe "A" is the target pipe and the pipe "B" is the whipping pipe. It should noted that if the target pipe is parallel with the plane defined by the plastic hinge and the force vector (jet from the end of the broken pipe) then contact will not occur. Figure 2 illustrates a configuration where the target line is not parallel to the whip plane. However, the reaction forces from a break in the horizontal section of pipe B will tend to push the whipping pipe away from target pipe A. This can be seen by severing the line in the horizontal section of line B and forming the plastic hinge at either anchor location. While this is a simplistic piping system and often times field application appears much more complex, piping systems can often be reduced to such geometries by field observations.

Reduction of complex piping systems to a simple model can be done with simplifying assumptions. First, one can normally assume a plastic hinge occurring at the second elbow (both upstream and downstream). While it is not always true that the second elbow away from the break location often yields the largest moment arm (and therefore have the greatest moment applied), it is not uncommon for second elbow to result in the longest moment arm. The second assumption is to maximize the moment, the jet force should be perpendicular to the moment arm. It should be known that these assumptions are not bounding. However, it should also be acknowledged that most piping systems are predominantly constructed of 90 degree elbows.

Other elbows geometries are present but occur much lower frequency. Considering that piping systems are constructed mostly of 90 degree elbows, inspection to determine the point in the piping system where the greatest moment arm is going to be generated is a simple act that can be accomplished with field inspections. Additionally, with the known direction of the reaction force from the jet, the anticipated travel of the whipping pipe can be anticipated.

Flailing of the Pipe While a pipe whip has been likened to a "fire hose" with whipping direction being unpredictable, this is not a fair characterization of a piping system. The main reason why the fire hose analogy is not appropriate is understanding why a fire hose flails. A fire hose is made of very tough but very weak material. When the jet comes from the end of a fire hose, the length of hose is placed in compression and the hose supports the force of the jet like a slender column. Because the

EC 16270 Page 14 of 38 SCREENING OF PIPE WHIP INTERACTIONS FOR Prepared By: DJP SDP Date: 06/02/2010 hose is weak (compared to the thrust load), flexure occurs at a mid-point in the hose. This flexure results in a change in the force vector where the load is no longer applied through the hinge point (assumed to be along the hose) and the hose moves laterally. However, in comparison to a pipe, the pipe will support the load created by jet force.

To illustrate this principle consider the following table which applies Euler's rule for slender columns:

Parameter Rubber Steel E [7]

1,000 psi [17]

2.9x10' psi L (Assumed Length) 25 ft 25 ft K (Radius of 2.245 in (6" Schedule 40 Pipe) 2.245 in (6" Schedule 40 Pipe) gyration, Assumed)

[7]

Tensile Strength 2,000 psi (Hypalon)[17]

36,000 psi [7]

(SR)T[7]

32 1

1 2Ff2E 2

1 i 2 E=2(1,000) 1 2

1 2

_z(2.6E7) 3

-S E

=21 (10 1.57 C

Sy 2

(36,000)

C S~

2 (2000) 0 Minimum length to

=(25ft)(12 (in/ft))/2.245 In= 133.6 (OK

=(25 ft)(12 (in/ft))/2.245 In= 133.6(OK to consider a slender to consider a slender column) consider a slender column) consider a slender column [7]

Sigma (e) [7]

are=

'2 E

,2(1,000) e 2E

,E 2 (2.9E7)

C Le (2 *25ft *l2in/ft) ~2 (CL 2___ (2*25ft*12in/ft)_

k) 2.245in

-k~J

~2 2

45~iin/f)

-e = 0.138psi oe =4007psi Therefore, in the application of Euler's to determine the allowable stresses for the same column, the allowable stress (and because the geometry is identical, the force) that can be applied to a rubber column is less than 1/2 9,0 0 0 th that of the same steel column prior to component buckling.

It is not reasonable to conclude that a pipe will behave in the same manner as rubber hose. The wild movement observed in a fire hose is the result of the column being too slender to support the axial loading resulting in the jet load exerting a lateral force and the process repeating. Due to the nature of the materials involved, random movement of a steel pipe would not be expected as a result of a jet leaving the end of the pipe.

It should be recognized that buckling needs the column to be considered slender.

slenderness ratio is the quotient of the length divided by the radius of gyration [7].

Slenderness Ratio =

Length Radius _of _ Gyration The The radius of gyration is based upon the parallel axis theorem. Therefore, it is not appropriate to simply subtract the outer pipe diameter radius of gyration from the inner pipe diameter radius of gyration. The rudimentary definition must be used [7].

EC 16270 Page 15 of 38 SCREENING OF PIPE WHIP INTERACTIONS FOR Prepared By: DJP SDP Date: 06/02/2010 Radius of _ Gyration J Area -Moment_ of _ Inertia Gyaio Area IOD ID AOD

-ID Where :

o= Area _ Moment_- of _ Inertia _ Based _ On _ Outside _ Diameter(In)

IID = Area _Moment ofInertia _Based

_On

_Inside

- Diameter(In')

AOD = Area _ Based _ On _ Outside _ Diameter(In2 )

AID = Area _ Based _ On - Inside - Diameter(jn2)

The Area Moment of inertia of a circle is determined as follows:

4 The critical slenderness ratio is between 80 and 120. For various diameters of schedule 40 piping, the piping length needed to be considered slender is as follows (using the lower critical ratio of 80).

NPS OD WALL I(OD)

I(ID)

I(OD)-

A RADIUS CRITICAL CRITICAL (IN)

THICKNESS (IN^4)

(INA4)

I(ID)

(INA2)

OF LENGTH LENGTH (IN)

(IN4)

GYRATION (IN)

(FT) 2.5 2.875 0.203 3.35 1.82 1.53 1.70 0.95 75.79 6.32 4

4.5 0.237 20.13 12.90 7.23 3.17 1.51 120.76 10.06 6

6.625 0.28 94.56 66.42 28.14 5.58 2.25 179.64 14.97 8

8.625 0.322 271.65 199.16 72.49 8.40 2.94 235.02 19.59 10 10.75 0.365 655.55 494.81 160.73 11.91 3.67 293.91 24.49 12 12.75 0.406 1297.21 997.00 300.21 15.74 4.37 349.33 29.11 16 16 0.5 3216.99 2485.05 731.94 24.35 5.48 438.63 36.55 20 20 0.593 7853.98 6150.27 1703.71 36.15 6.86 549.17 45.76 The critical length where slender column equations apply (where buckling failures occur in lieu of compressive material failure) are shown above for various schedule 40 pipes. The ratio of critical length to pipe diameter is approximately 26.

Determining pressure and thrust to buckle piping is as follows[8]:

= Thrust A*K Where:

K = 1.26[8]

A = Pipe _ Flow_ Area (1n 2)

Thrust = Thrust -Force (lbf )

EC 16270 Page 16 of 38 SCREENING OF PIPE WHIP INTERACTIONS FOR Prepared By: DJP SDP Date: 06/02/2010 NPS RADIUS CRITICAL SIGMA E PIPE METAL THUST INTERNAL PRESSURE OF LENGTH AREA (IN^2)

FORCE(LBF)

AREA REQUIRED GYRATION (IN)

(IN^2)

TO CAUSE FAILURE (PSI) 2.5 0.95 75.79 11180.41 1.704 19052 4.79 3158 4

1.51 120.76 11180.41 3.174 35487 12.73 2212 6

2.25 179.64 11180.41 5.581 62402 28.89 1714 8

2.94 235.02 11180.41 8.399 93907 50.03 1490 10 3.67 293.91 11180.41 11.908 133140 78.85 1340 12 4.37 349.33 11180.41 15.745 176031 111.93 1248 16 5.48 438.63 11180.41 24.347 272213 176.72 1223 20 6.86 549.17 11180.41 36.155 404223 278.00 1154 From review of references [9], [10], and [16], pressures do not exist in the system that could cause piping failure at the given column lengths.

Break Plane perpendicular to the piping axis The break plane is presumed to be perpendicular to the axis of the piping. Breaks of this geometry are only logical based on piping failure modes. For piping to break and have significant displacement, the piping must sever. If the piping does not sever, the remaining ligament will act as an tether preventing significant displacement of the piping at the break location. With a complete severanceof the piping, the remaining restraint is the piping systems ability to resist the bending moment imparted by the jet forces.

For break to occur, either the internal forces within the pipe must exceed the allowable stress limits of the piping or the combined stresses induce a failure. If the forces are a result of internal pressure, axial stresses are 1/2 that of circumferential stress, therefore a longitudinal break is the outcome. As discussed previously, a longitudinal break is not expected to cause significant pipe whip displacement.

However, if the axial stress combined with other loads (dead weight, seismic, thermal stresses, etc) would cause the piping failure, then the break plane would be perpendicular to the pipe axis.

The axial stress generated by internal loads is discussed previously but does add at the axial stress. The axial stress state of the pipe will be defined as follows [7]:

EC 16270 Page 17 of 38 SCREENING OF PIPE WHIP INTERACTIONS FOR Prepared By: DJP SDP Date: 06/02/2010 P

Compression Neutral Axis Tension t

~

-y Mc

-b,max IC Where :

M = Applied_ Moment c = Maximum Dis tan ce From the Neutral Axis Ic= Area Moment_ of_ Material The principle of superposition can be utilized to apply additional stresses from the internal pressure loads. This would result in more tension be added to the material in tension, and less compressive stress for the material in compression. Therefore, this would also result in a shift in the neutral axis. Ultimately, the piping material would fail first where the stress is the highest.

Assuming the material is uniform (long pipe with no stress concentrators), the area of failure is the location of greatest moment is applied. Because the nature of this evaluation is a random failure, this applied moment could occur anywhere. However, if the random load is applied and local failure occurs, the first material failure would occur at the material in tension furthest away from the neutral axis. Because of this failure, the area moment of the beam will decrease where the material failure is occurring, weakening the pipe locally. The process would then be repeated until the moment load completely severed the pipe. Therefore it is only reasonable to conclude that, for a randomly assumed break due to an applied excessive moment load, the break plane will be perpendicular to the axis of the piping system.

Jet forces Generated The forces generated to cause pipe whip are from two areas but are from the same principles.

The principle being applied is a change in momentum. Consider the following piping system:

EC 16270 Page 18 of 38 SCREENING OF PIPE WHIP INTERACTIONS FOR Prepared By: DJP SDP Date: 06/02/2010 x

Yl A

B Flow C

In this figure, momentum changes which cause a moment about point "C" occur at two points, A and B. This is the "Impulse-Momentum Principle". The forces generated at point "A" are a result of the fluid changing direction at the elbow. The fluid is changing direction from the Y direction to the X direction. Note that the change in force resulting from the change in the Y direction momentum is through the hinge point and therefore applies zero moment. The impulse momentum equation can be reduced to the following:

Forces due to the elbow (Point A) in the X-direction [71:

Fm Av mAv

_ m(via-Vxnitiala)=

m(Vxfina

--o)_

m(Vxfn) gx,

• g=

gc g

-(vfnl Force due to the exit of the pipe F

M mAy m A vx m(vxfinal - Vxiniiai )

Fx,B ca be c a

These forces can be combined as follows:

EC 16270 Page 19 of 38 SCREENING OF PIPE WHIP INTERACTIONS FOR Prepared By: DJP SDP Date: 06/02/2010 m(v xfinaA )

m(Vxfina! -

Vx"ni(tiaB) =m (VxfinaIA + VxftnaI -

Vx)iniiagB Fxtlotai =FxA+/-FXB=

9

+

91 At the instant of the break at point "B", the initial velocity will equal the final velocity at point A.

However, if the mass flow rate of the system is not sufficient to support the choked flow at point "B", the sonic plane will move back through the pipe until the pipe is depressurized or a minimum cross sectional area of the pipe is encountered where the upstream velocity is sufficient to maintain the choked flow at that throat.

Case A Case B Case C Assuming the break occurs instantaneously ( and the conditions are present for choked flow), the flow will be instantaneously choked perpendicular to the break plane for an instant. However, the sonic plane will move back up through the pipe to the smallest area upstream break location as the fluid in the pipe depressurizes. As a matter of fact, the sonic plane will continue to migrate through the pipe dependant upon the velocity of the fluid feeding the system. As such, the fluid exiting the pipe will have velocity vectors aligned predominantly axially with the pipe.

There are some minor exceptions, the fluid leaving the pipe will expand (either steam or water flashing to steam) and cause a lateral force to the end of a beveled pipe. These forces are negligible compared to the overall forces acting axially along the pipe and should not cause the reactions forces shown in Case C.

EC 16270 Page 20 of 38 SCREENING OF PIPE WHIP INTERACTIONS FOR Prepared By: DJP SDP Date: 06/02/2010 Justification of Order This element basically determines if the pipe will even make contact. If the whipping pipe does not make contact with the target pipe, then damage cannot occur.

Flowchart Implementation Element 1-Included in CC HELB SDP Reference [15] is the final report associated with CC/HELB significance determination. This report describes which lines were considered to be flooding sources coincident the component cooling water line.

The following interactions were excluded on this basis:

11, 16, 39, 40, 41 and 42 Element 2-Is the moving pipe normally isolated?

ENG-ME-732 Revision 0 did not identify which pipes were normally isolated.

ENG-ME-732 Revision 1 did exclude interactions due to the high energy line being meeting the HELB rules less than 2% of normal expected operation.

The following interactions were excluded on this basis:

1 through 6, 8, 17, 86 through 94, 96, 97 and 108 Element 3-Is the target pipe so small that it does not contribute to the SDP (4")?

ENG-ME-732 Revision 0 and Revision 1 (which correct some discrepancies with target line designations). The following lines are excluded as their nominal pipe size is less than 4".

21, 24, 25, 29, 30, 48a, 48b, 57, 58,59, 62, 63, 72a, 98 through 107, 116, 116a, 119, 122a, 124,125, 138a, 141,143,150,152,157 Element 4-Does the target pipe have cast iron component that could fail?

The following interactions were reviewed to determine if a cast iron valve or support was in the system that would affect it ability to absorb an impact. In this regard, only interactions that could possibly be screened out by element 5 (the moving pipe is not thicker than the target pipe were reviewed). The remaining interactions were assumed to have cast iron.

EC 16270 Page 21 of 38 SCREENING OF PIPE WHIP INTERACTIONS FOR Prepared By: DJP SDP Date: 06/02/2010 Interaction Target Line Basis Reference(s) 10 14-CL-110 14-CL-1 10 was walked

[12],[18]

down in the Unit 1 TB. No valves were identified on that line with exception of CL-35-1. CL-35-1 valve body is identified as A-516 Gr 70.

14 16-CL-67 16-CL-67 was reviewed on

[12]

Ref [12]. No valves are present on 16-CL-67.

Upstream the line has MV-32031. MV-32031 valve body is identified as A-516 Gr 70. Attached line 14-CL-67 does have a cast valve in it (CW-32-1). Passport indicates the valve is cast steel [11]. The 14" line is not structurally significant to 16-CL-67. Impacts to 16-CL-67 from 12-CD-7 (or 20-CD-7) will provide axial loading to CW-32-1 which would be non-consequential. 16-CL-67 pipe will deform (along with 12-CD-7 or other laterally impacting pipe) to absorb most of the energy from the event.

15 16-CL-67 See Interaction 14

[12]

18 16-CL-67 See Interaction 14

[12]

19 16-CL-67 See Interaction 14

[12]

20 24-CL-110 24-CL-110 was walked

[12], [19]

down in the Unit 1 TB. No valves were identified on that line with exception of CL-34-1. CL-34-1 valve body is identified as A-515 Gr 70..

20a 24-CL-1 10 See Interaction 20 48 24-CL-1 10 See Interaction 20 49 24-CL-110 See Interaction 20 56 24-CL-110 See Interaction 20 60 24-CL-1 10 See Interaction 20 109 16-2CL-9 No valves were identified on

[18], [13]

16-2CL-9. Upstream the line

EC 16270 Page 22 of 38 SCREENING OF PIPE WHIP INTERACTIONS FOR Prepared By: DJP SDP Date: 06/02/2010 Interaction Target Line Basis Reference(s) has MV-32033. MV-32033 valve body is identified as A-516 Gr 70 Attached line 14-2CL-10 does have a cast iron valve in it (2CL-32-1).

The 14" line is not structurally significant to 16-2CL-9. Impacts to 16-2CL-9 from 16-2CD-3 will provide axial loading to 2CL-32-1 which would be non-consequential. 16-2CL-9 pipe will deform (along with 16-2CD-3) to absorb most of the energy from the event.

114 16-2CL-9 See Interaction 109 115 16-2CL-9 See Interaction 109 121 16-2CL-9 See Interaction 114 123 24-2CL-56 The only valve on 24-

[18], [13]

2CL-56 is 2CL-34-1.

Reference 18 identifies 2CL-34-1 1 valve body is identified as A-516 Gr 70.

134 14-ZX-161 The only valve shown

[18], [14]

on line 14-ZX-161 in reference 14 is CL-1 14-

1. Reference 18 identifies CL-1 14-1 valve body is identified as A-516 Gr 70.

135 14-ZX-161 See Interaction 134 136 14-ZX-161 See Interaction 134 142 14-ZX-161 See Interaction 134 151 16-ZX-128 The only valve shown

[11],[13]

on line 16-ZX-128 in reference 13 is ZX 1. Reference 11 identifies zx-1 9-1 with the material identifier "CS".

161 24-2CL-56 See interaction 123 164 24-2CL-56 See interaction 123 168 24-2CL-56 See interaction 123 169 24-2CL-56 See interaction 123

EC 16270 Page 23 of 38 SCREENING OF PIPE WHIP INTERACTIONS FOR Prepared By: DJP SDP Date: 06/02/2010 Interaction Target Line Basis Reference(s) 181 14-ZX-161 See Interaction 134 182 14-ZX-161 See Interaction 134 183 14-ZX-161 See Interaction 134 184 14-ZX-161 See Interaction 134 185 14-ZX-161 See Interaction 134 187 14-ZX-161 See Interaction 134 188 14-ZX-161 See Interaction 134 189 14-ZX-161 See Interaction 134 190 14-ZX-161 See Interaction 134 191 14-ZX-161 See Interaction 134 192 14-ZX-161 See Interaction 134 Element 5-Is the moving pipe thicker than the target pipe?

This screening criteria is only applicable to lines that do not have cast iron components in them. Therefore, only items listed in element 4 can be screened out. (See element 4 above).

Additionally, only pipes where the moving pipe was equal to or thinner than the target pipe wall thickness was document in element 4.

Based upon the computer simulations conducted, the following interactions were successfully modeled to indicated that only minor (if any) would occur from the target piping.

14, 15, 18, 19, 20, 20a, 48, 49, 56, 60, 109, 114,115, 118, 121,123, 134, 135, 136, 142, 161, 164, 168, 169, 181, 182, 183, 184, 185, 187 through 192.

Interaction 151 was a limiting case that did not successfully pass computer simulation. Therefore, it will not be excluded from the SDP based upon criteria in element 5 and will be reviewed in element 6.

Interaction 10, while meeting the criteria of this block, cannot be considered bounding by [6]. Therefore, it will not be excluded from the SDP based upon criteria in element 5 and will be reviewed in element 6.

Element 6-Does geometry preclude interaction between the moving piping and the target pipe?

The following interactions have been evaluated to conclude that the likelihood of interaction is low based upon the geometric configuration of the target and

EC 16270 Page 24 of 38 SCREENING OF PIPE WHIP INTERACTIONS FOR Prepared By: DJP SDP Date: 06/02/2010 moving pipes. The detailed write-up for each interaction is included in of this evaluation.

10, 12, 13, 43, 46, 53, 58, 76, 82, 110, 111, 112, 113, 117, 151, 155, 156, 157, 159,160,163,180,198,199 Remaining Interactions The following interactions did not meet the screening criteria above and should therefore be included fully in the SDP.

7, 9, 22, 23, 26 through 28, 31 through 38, 39a, 40a, 44, 45, 47, 50, 51, 52, 54, 55, 61, 64 through 72, 73, 74, 75, 77, 78, 79, 81, 83, 84, 85, 95, 120, 122, 126 through 133, 137, 138, 139, 140, 144 through 149, 153, 154, 158, 158a, 159a, 162, 165, 166, 167, 170 through 179, 186, 193 through 197, 200, 201, 202, 203, 204,205.

Conclusions This evaluation has determined the interactions that should be included in the SDP. The criteria used to determine whether the interaction should be included is based upon the following flow chart.

EC 16270 Page 25 of 38 SCREENING OF PIPE WHIP INTERACTIONS FOR Prepared By: DJP SDP Date: 06/02/2010 Has the interaction been evaluated in CCHELB SDP?

No L,*Excluded from this SDP

~Exclude from SDP 21 Is moving pipe normally isolated/

Denergized?

No, 31 Is the target less than 4" NPS?

No

{ Does the target have a cast iron Component that could fail?

Will not contribute Significantly, does not Warrant further investigation In this EC No AES analysis Supports no 10, Target damage, Excluded from interaction set No, 51 Is moving pipe thicker than target pipe?

Yes I Has the interaction been geometrically analyzed and concludes target pipe damage is minimal?

yes No Can not conclude target pipe receives minimal damage Not Considered a piping interaction.

Excluded Of the original 218 interactions, total lines were excluded as follows:

Element Number Total Number Interactions Excluded Previously Evaluated in CC/HELB 6

Normally Isolated 22 Less than 4" NPS 35 Not cast Iron and moving pipe not thicker than 34 target Geometry limited from interacting 24 Total Excluded 121 There are 98 interactions remaining following this screening whose numbers are listed above in the appropriate section.

Again, it is worth noting that several of the remaining items could be excluded if items in the "inherent conservatisms" section were implemented. However, these criteria tend to require specific analysis and did not lend themselves to a generic analysis but with additional resources could be applied to reduce the remaining interactions to less than 98.

EC 16270 Page 26 of 38 SCREENING OF PIPE WHIP INTERACTIONS FOR Prepared By: DJP SDP Date: 06/02/2010 It should also be noted the inherent conservatism are also applicable to items screened out due to geometry. For instance, many items whose geometry is not conducive to pipe whip affecting the target piping have very small distances between the moving pipe and the target pipe. Additionally, the piping geometries may not lend themselves to the generation of kinetic energy due to the work required to form the plastic hinges in the moving pipe. As a result of these inherent conservatism, the overall result of this analysis is conservative as it tends to over populate the interactions required to fully evaluate.

References

1. Calculation CA-1998-04320 (Film Location 3498-2714)

2. ENG-ME-732 (Revision 0 and Revision 1), "Determination of HELB / Flooding Interactions in the Turbine Building"

3. NUREG CR-3231, "Pipe-to-Pipe Impact Program"

4. Branch Technical Position MEB 3-1.

5. ENG-ME-358 Rev 1, "APPENDIX I - HELB - PIPING SYSTEM SELECTION"

6. EC16275, "EFFECTS OF PIPE WHIP INTERACTIONS FOR VARIOUS PIPE COMBINATIONS For Internal Flooding SDP"

7. Mechanical Engineering Reference Manual, Lindeberg, Twelfth Edition

8. ENG-ME-369 Rev 0, "JET IMPINGEMENT FOR HIGH ENERGY LINE BREAKS"

9. USAR Figure 11.2-5 Rev 30

10. USAR Figure 11.2-1 Rev 27

11. Passport Equipment Database

12. NF-39216-2 Rev 77

13. NF-39217-1 Rev 78

14. NF-86172-1 Rev 76

15. PINGP Report "Component Cooling Water / Turbine Building SDP Issue Risk Significance" Dated 6/5/2009

16. USAR Figure 11.2.4 Rev 27

17. Dupont Hypalon Synthetic Rubber Engineering Properties

18. Technical Manual XH-195-22, "Pratt Butterfly Valves"

19. Drawing XH-195-1, "Model Ri-a Butterfly Valve

20. EPRI Technical Report 1010059, Service Water Piping Guideline

21. EC 15656, "EVALUATION OF FLOODING TIMES AND FLOW RATES ASSOCIATED WITH UNIT 1 AND UNIT 2 TB FOR SIGNIFICANCE DETERMINATION"

22. Crane Technical Paper No.410,

23. NSP Technical Manual Number X-HIAW-48-24, "#11, #21 Cooling Water Pump."

24. EC16090, "TURBINE BUILDING FLOODING SDP: CL TURBINE BUILDING PIPE BREAK ANALYSIS" Attachments A. Walk down exclusion write-ups B. Base Spreadsheet from ENG-ME-732 Rev 0 (Amended with Rev 1 information if needed) with interaction review data.

EC 16270 Page 27 of 38 SCREENING OF PIPE WHIP INTERACTIONS FOR Prepared By: DJP SDP Date: 06/02/2010 Attachment A Interaction 10 Interaction 10 is between 20-CD-7 and 14-CL-1 10 with the break occurring in Row B Column 2 Elevation 695. The interaction is shown on Scientel Drawing A52a and A52b. The high energy line is identified as P2 in those drawings. The direction of whip will be along the plane generated by the axis of pipe where the break occurs and the plastic hinge point. There are two elbows on 20-CD-7 which direct the west 45 degrees up from the horizontal plane followed be a 90 degree to the southbound run in a horizontal plane. As shown in plan view of A52a and plan view of A52b, 14-CL-110 runs under the southbound horizontal section of 20-CD-7. Break locations are assumed anywhere along the length of the line.

Assuming a break occurs in the east-west section of 20-CD-7, the upstream pipe will thrust axially to the west but will not whip. The downstream section of piping will rotate in the horizontal plane but not move toward 14-CL-1 10.

Postulating a break between the two elbows will result in the upstream pipe thrusting down and north, away from 14-CL-1 10. The downstream pipe will thrust upward and rotate clockwise (looking down) away from 14-CL-110 pipe (which runs underneath this section of pipe).

Lastly, should the break occur down stream of the second elbow in this pipe segment, the upstream pipe will be pushed north and will tend to rotate up and away from the 14-CL-1 10. The downstream segment will receive an axial load but will not bend as not moment will be generated to develop a plastic hinge.

Therefore, this interaction is excluded as an initiating event for this SDP.

Interaction 12 Interaction 12 is between lines 20-CD-7 and 14-CL-67 with the break occurring in Row B Column 3 Elevation 695. The interaction is shown on Scientel Drawing A52a. The high energy line is identified as P1 in isometric view of A52a. The direction of whip will be along the plane generated by the axis of pipe where the break occurs and the plastic hinge point. There are two elbows on 20-CD-7 which direct its flow from the west to 45 degrees up from a horizontal plane to finally a southbound run in a horizontal plane. As shown in plan view of A52a and plan view of drawing A52b, 14-CL-67 runs over the east west horizontal section of 20-CD-7. Break locations are assumed anywhere along the length of the line.

Break locations upstream of the elbows would result in an axial load on 20-CD-7

EC 16270 Page 28 of 38 SCREENING OF PIPE WHIP INTERACTIONS FOR Prepared By: DJP SDP Date: 06/02/2010 but no moment is generated on the pipe while the downstream pipe moves away from the target pipe described in this interaction. The upstream pipe would not experience movement. Breaks downstream of the elbows would result in upstream section 20-CD-7 thrusting down and North, away from 14-CL-67.

Therefore, this interaction is excluded as an initiating event for this SDP.

Interaction 13 Interaction 13 is between line 20-CD-7 and target line 14-CL-84 in Row B, Column 3, elevation 695. The interaction is shown on Scientel drawing A52a.

Line 14-CL-84 runs vertically, south of 20CD-7 turning south into row C column

3. Breaks in 20-2CD-7 will cause the upstream section of 20-2CD-7 to thrust north, down & west, or west (depending on the assumed location of the break).

The downstream section will rotate clockwise (in plan view shown in A52b) away from the target pipe.

Therefore, this interaction is excluded as an initiating event for this SDP.

Interaction 43 Interaction 43 is between 16-FW-1 and 24-CL-1 10 with the break occurring in Row F Column 4 Elevation 695. The interaction is shown on Scientel Drawing A45. The high energy line is identified as P1 in those drawings. The direction of whip will be along the plane generated by the axis of pipe where the break occurs and the plastic hinge point. The pipe will tend to thrust up through the grating, moving past 24-CL-1 10. As no lateral thrust load is generated by the break, it is reasonable to conclude that no interaction will occur with 24-CL-1 10 as the 715 grid decking and steel structure will prevent lateral movement. The minimal lateral movement would result in incidental (if any) contact with 24-2CL-110 whose centerline is 24" south.

Therefore, this interaction is excluded as an initiating event for this SDP.

Interaction 46 Interaction 46 is between 16-FW-1 and 6" FP line with the break occurring in Row F Column 4 Elevation 695. The interaction is shown on Scientel Drawing A45. The high energy line is identified as P1. The direction of whip will be along the plane generated by the axis of pipe where the break occurs and the plastic hinge point. The pipe will tend to thrust up through the grating, moving past 6" FP line. Movement will continue until 16-FW-1 makes contact with the 735 ceiling.

As no lateral thrust load is generated by the break, it is reasonable to conclude that no interaction will occur with 6" FP as the 715 grid decking and steel structure will tend to prevent lateral movement. The minimal lateral movement

EC 16270 Page 29 of 38 SCREENING OF PIPE WHIP INTERACTIONS FOR Prepared By: DJP SDP Date: 06/02/2010 would result in incidental (if any) contact with 24-2CL-1 10 whose centerline is 24" south.

Therefore, this interaction is excluded as an initiating event for this SDP.

Interaction 53 Interaction 53 is between 16-CD-10 and 6" FP line with the break occurring in Row F Column 5 Elevation 695. The interaction is shown on Scientel Drawing A41. The high energy line is identified as P1. The direction of whip will be along the plane generated by the axis of pipe where the break occurs and the plastic hinge point. The pipe will tend to thrust up through the grating, moving past 6" FP line. As no lateral thrust load is generated by the break, it is reasonable to conclude that no interaction will occur with 6" FP as the 715 grid decking and steel structure will prevent lateral movement.

Therefore, this interaction is excluded as an initiating event for this SDP.

Interaction 58 Interaction 58 is between 3-MS-5 and various fire protection piping with the break occurring in Row F Column 7 Elevation 695. 3-MS-5 is enclosed in an engineered steel enclosure which prevent pipe whip. This enclosure is secured closed with a lock and administratively closed with shift supervision permission to open the enclosure during normal operations. This enclosure would prevent a failed pipe within the enclosure from whipping and affecting the fire protection piping adjacent to the enclosure from being affected.

Therefore, this interaction is excluded as an initiating event for this SDP.

Interaction 76 Interaction 76 is between 16-FW-3 and 6" fire protection line with the break occurring in Row F Column 5 Elevation 715'. The interaction is shown on Scientel Drawing A46a and A46b. The high energy line is identified as P4 and P5 in those drawings. The 6" FP line runs horizontally 3' over 16-FW-3 then turns vertically down through the floor grating approximately 8' south of the horizontal section of 16-FW-3. The direction of whip will be along the plane generated by the axis of pipe where the break occurs and the plastic hinge point. If the break is assumed to occur in the vertical section from the 11 FWP, the ceiling will prevent significant travel of the whipping pipe. In this case, the 6" FP line (which is located some distance from the assumed break location) would not be contacted.

Breaks occurring in the east-west horizontal section of 16-FW-3 will not affect the 6" FP line either. The assumed break locations in the horizontal section will not cause a thrust vertical upward. The assumed break location will cause piping west of the break location to receive a westward force and the piping east of the break location to receive an eastward force. The piping to the west of the break location will have limited travel due to two 16" pipes (16-FW-3 and 16-CD-1 0)

EC 16270 Page 30 of 38 SCREENING OF PIPE WHIP INTERACTIONS FOR Prepared By: DJP SDP Date: 06/02/2010 associated with the FWP inlet and discharge. The east ward pipe has upstream elbows that would tend to cause piping movement to the north (which is the opposite direction of the 6" FP vertical section). Assuming a break downstream of the elbow that directs flow from west to north will cause the upstream piping segment to thrust south causing 16-FW-3 to strike the G-line wall prior to contact with the 6" FP line.

Therefore, this interaction is excluded as an initiating event for this SDP.

Interaction 82 Interaction 82 is between 16-FW-3 and 10-FP-31 fire protection line with the break occurring in Row F Column 4 Elevation 715'. The interaction is shown on Scientel Drawing A46a and A46b. The 10-FP-31 line runs horizontally 4'6" above and 5' 6" south of 16-FW-3. The direction of whip will be along the plane generated by the axis of pipe where the break occurs and the plastic hinge point.

Breaks occurring in the east-west horizontal section of 16-FW-3 will not affect the 10-FP-31 line. The assumed break locations in the horizontal section will not cause a thrust vertical upward. The assumed break location will cause piping west of the break location to receive a westward force and the piping east of the break location to receive an eastward force. The piping to the west of the break location will have limited travel due to two 16" pipes (16-FW-3 and 16-CD-10) associated with the 12 FWP inlet and discharge lines. The east ward pipe has upstream elbows that would tend to cause piping movement to the north (which is the opposite direction of the 10-FP-31). Breaks in the vertical section of 16-FW-3 will cause and upward thrust which will limit travel and preclude additional contact.

Therefore, this interaction is excluded as an initiating event for this SDP.

Interaction 110 Interaction 110 is between lines 20-2CD-7 and 10-2CL-53 with the break occurring in Row B Column 14 Elevation 695. The interaction is shown on Scientel Drawing A54. The high energy line is identified as P1 in isometric view of A54. The direction of whip will be along the plane generated by the axis of pipe where the break occurs and the plastic hinge point. There are two elbows on 20-2CD-7 which direct its flow from the east 45 degrees up from a horizontal plane to finally a southbound run in a horizontal plane. As shown in plan view of A54, 10-2CL-53 runs skew of 20-2CD-7. Break locations are assumed anywhere along the length of the line 20-2CD-7. Break locations upstream of the elbows would result in an axial load on 20-2CD-7 but no moment is generated on the pipe while the downstream pipe moves away from the target pipe described in this interaction. The upstream pipe would not experience movement. Breaks downstream of the elbows would result in upstream section 20-CD-7 thrusting down and North, away from 10-2CL-53. The horizontal section of 20-2CD-7

EC 16270 Page 31 of 38 SCREENING OF PIPE WHIP INTERACTIONS FOR Prepared By: DJP SDP Date: 06/02/2010 would thrust towards the "C" line but no moment is applied and therefore no whipping would be expected.

Therefore, this interaction is excluded as an initiating event for this SDP.

Interaction 111 Interaction 111 is between lines 20-2CD-7 and 10-2CL-56 with the break occurring in Row B Column 14 Elevation 695. The interaction is shown on Scientel Drawing A54. The high energy line is identified as P1 in isometric view of A54. The direction of whip will be along the plane generated by the axis of pipe where the break occurs and the plastic hinge point. There are two elbows on 20-2CD-7 which direct its flow from the east 45 degrees up from a horizontal plane to finally a southbound run in a horizontal plane. As shown in plan view of A54, 10-2CL-56 runs under the of southbound section 20-2CD-7. Break locations are assumed anywhere along the length of the line 20-2CD-7. Break locations upstream of the elbows would result in an axial load on 20-2CD-7 but no moment is generated on the pipe while the downstream pipe moves away from the target pipe described in this interaction. The upstream pipe would not experience movement. Breaks downstream of the elbows would result in upstream section 20-2CD-7 thrusting down and North, away from 10-2CL-56.

The horizontal section of 20-2CD-7 would thrust towards the "C" line but no moment is applied and therefore no whipping would be expected.

Therefore, this interaction is excluded as an initiating event for this SDP.

Interaction 112 Interaction 118 is between line 20-2CD-7 and target line 14-2CL-10 in Row B, Column 14, elevation 695. The interaction is shown on Scientel drawing A54.

Breaks in 20-2CD-7 in will cause the section of 20-2CD-7 to thrust north, down &

east, or east (depending on the assumed location of the break). Due to one elbow, 14-2CL-10 passes over the horizontal straight length of 20-2CD-7 running east-west through row B column 14. There is no hinge point generated in the horizontal section of 20-2CD-7 as no moment arm is generated. Breaks in the elbows of 20-2CD-7 will cause the southbound section of 20-2CD-7 to thrust up and away from 14-2CL-10.

Therefore, this interaction is excluded as an initiating event for this SDP.

Interaction 113 Interaction 113 is between lines 20-2CD-7 and 14-2CL-53 with the break occurring in Row B Column 14 Elevation 695. The interaction is shown on Scientel Drawing A54. The high energy line is identified as P1 in isometric view of A54. The direction of whip will be along the plane generated by the axis of pipe where the break occurs and the plastic hinge point. There are two elbows on 20-2CD-7 which direct its flow from the east 45 degrees up from a horizontal

EC 16270 Page 32 of 38 SCREENING OF PIPE WHIP INTERACTIONS FOR Prepared By: DJP SDP Date: 06/02/2010 plane to finally a southbound run in a horizontal plane. As shown in plan view of A54, 14-2CL-53 runs skew vertically adjacent to the east west section of 20-2CD-7 passing through Row B Column 14. Break locations are assumed anywhere along the length of the line 20-2CD-7. Break locations upstream of the elbows would result in an axial load on 20-2CD-7 but no moment is generated on the pipe while the downstream pipe moves away from the target pipe described in this interaction. The upstream pipe would not experience movement. Breaks downstream of the elbows would result in upstream section 20-2CD-7 thrusting down and North, away from 14-2CL-56. The horizontal section of 20-2CD-7 would thrust towards the "C" line but no moment is applied and therefore no whipping would be expected.

Therefore, this interaction is excluded as an initiating event for this SDP.

Interaction 117 Interaction 117 is between lines 20-2CD-7 and 6-2CL-9 with the break occurring in Row B Column 14 Elevation 695. The interaction is shown on Scientel Drawing A54. The high energy line is identified as P1 in isometric view of A54.

The direction of whip will be along the plane generated by the axis of pipe where the break occurs and the plastic hinge point. There are two elbows on 20-2CD-7.

The first direct its flow from the east 45 degrees up from a horizontal plane to finally a southbound run in a horizontal plane. As shown in plan view of A54, 6-2CL-9 runs above adjacent to the east west section of 20-2CD-7 passing through Row B Column 14. Break locations are assumed anywhere along the length of the line 20-2CD-7. Break locations upstream of the elbows would result in an axial load on 20-2CD-7 but no moment is generated on the pipe while the downstream pipe moves away from the target pipe described in this interaction.

The upstream pipe would not experience movement. Breaks downstream of the elbows would result in upstream section 20-2CD-7 thrusting down and North, away from 6-2CL-9. The horizontal section of 20-2CD-7 would thrust towards the "C" line but no moment is applied and therefore no whipping would be expected.

Therefore, this interaction is excluded as an initiating event for this SDP.

Interaction 151 Interaction 151 is between line 20-2CD-7 and target line 16-ZX-128 in Row E, Column 15, elevation 695. The interaction is shown on Scientel drawing A54.

Breaks in 20-2CD-7 near 16-ZX-1 28 will cause the upstream section of 20-2CD-7 to thrust north and the down stream section to swing up and to the east. The 16-ZX-128 is above 20-2CD-7 by approximately 24". There is no hinge point generated in the horizontal section of 20-2CD-7 as no moment arm is generated.

Breaks in 20-2CD-7 near 16-2CD-7 will cause the southbound section of 20-2CD-7 to thrust up and away from 16-ZX-128 while the horizontal piping near 16-ZX-128 will thrust down and away from the ZX line.

EC 16270 Page 33 of 38 SCREENING OF PIPE WHIP INTERACTIONS FOR Prepared By: DJP SDP Date: 06/02/2010 Therefore, this interaction is excluded as an initiating event for this SDP.

Interaction 155 Interaction 155 is between 16-2FW-3 and 24-2CL-56 with the break occurring in Row F Column 10 elevation 695. The interaction is shown on Scientel Drawing A49C and A49A. The line is identified as P1 in those drawings. Breaks in 16-2FW-3 (interaction 160, south 25 FW Heater) are below the 715 grating. The direction of whip will be along the plane generated by the axis of pipe where the break occurs and the plastic hinge point. As shown in plan view of A49C and plan view of drawing A49C, the section of piping below the 715 grating runs only in a vertical plane and therefore its whip would only be a vertical plane along the axis of the horizontal section of piping. The plan view of drawing A57 indicates that the vertical plane passing through 16-2FW-3 is offset by 5' from 24-2CL-56.

Thus should a break occur in 16-2FW-3, it will pass by 24-2CL-56 with no contact.

Therefore, this interaction is excluded as an initiating event for this SDP.

Interaction 156 Interaction 156 is between 20-2FW-3 and 24-2CL-56 with the break occurring in Row F Column 10 elevation 695. The interaction is shown on Scientel Drawing A57. The line is identified as P1 in those drawings. Breaks in 20-2FW-3 (interaction 160, south 25 FW Heater) are below the 715 grating. The direction of whip will be along the plane generated by the axis of pipe where the break occurs and the plastic hinge point. As shown in plan view of A57 and plan view of drawing A49b, the section of piping below the 715 grating runs only in a vertical plane and therefore its whip would only be a vertical plane along the axis of the horizontal section of piping. The plan view of drawing A57 indicates that the vertical plane passing through 20-2FW-3 is offset by 5' from 24-2CL-56. Thus should a break occur in 20-2FW-3, it will pass by 24-2CL-56 with no contact.

Therefore, this interaction is excluded as an initiating event for this SDP.

Interaction 157 Interaction 157 is between 3-2MS-6 and various fire protection piping with the break occurring in Row F Column 10 Elevation 695. 3-2MS-6 is enclosed in an engineered steel enclosure which prevent pipe whip. This enclosure is secured closed with a lock and administratively closed with shift supervision permission to open the enclosure during normal operations. This enclosure would prevent a failed pipe within the enclosure from whipping and affecting the fire protection piping adjacent to the enclosure from being affected.

Therefore, this interaction is excluded as an initiating event for this SDP.

EC 16270 Page 34 of 38 SCREENING OF PIPE WHIP INTERACTIONS FOR Prepared By: DJP SDP Date: 06/02/2010 Interaction 159 Interaction 159 is an interaction between 20-2FW-3 and 14-ZX-161 with the break occurring in Row F column 11 elevation 695. This interaction is shown on Scientel Drawing A57. The line connects to the southern most 25 feedwater heater and runs approximately 3.5' below the 715 grating. Based upon the physical lengths of pipe available to whip, a break in line 20-2FW-3 attached to the north feedwater heater will not impact 14-ZX-161. See sketch below.

2-5 B

- \\ý,/

r H.

It- = -1 S'-

11 C L :- -? i-7 0

S CLI 7~/-7~ CL EV*Zz7bAK~~

- /4'-Zx 1/G Q ~-2Pw -3 VIEW Creating a limiting length of whipping pipe by a circumferential break, if the breaks at valve 2FW-1 1-1 and hinges at the 715' grating penetration, the length

EC 16270 Page 35 of 38 SCREENING OF PIPE WHIP INTERACTIONS FOR Prepared By: DJP SDP Date: 06/02/2010 of the swinging arm is 8.76". The 14-ZX-161 line is 10.5' below the 715' grating.

Therefore, the whipping arc is not sufficient in length.

Creating a limiting length of whipping pipe by a circumferential break, if the breaks at 715' grating penetration and hinges in line 16-2FW-3, the swing radius is:

S/(715-711.)5+yc,

=

(

c,2 Where:

C1 = the horizontal distance from the break location to hinge The 14-ZX-161 line is 10.5' below the 715' grating. The radius of the ZX line to the hinge point is:

I (711.s-704.s42)2 +C 1 2 =

958)' +C,2 Therefore, the whipping arc is not sufficient in length because

• (3.5)2 +C 1 2 <

(6.958)2 +C12 Interaction is not possible due to pipe lengths and hinge points and is therefore excluded as an initiating event for this SDP.

Interaction 160 Interaction 160 is between 20-2FW-3 and 24-2CL-56 with the break occurring in Row F Column 11 elevation 695. The interaction is shown on Scientel Drawing A57. Breaks in 20-2FW-3 (interaction 160, south 25 FW Heater) are below the 715 grating. The direction of whip will be along the plane generated by the axis of pipe where the break occurs and the plastic hinge point. As shown in plan view of A57 and plan view of drawing A49b, the section of piping below the 715 grating runs only in a vertical plane and therefore its whip would only be a vertical plane along the axis of the horizontal section of piping. The plan view of drawing A57 indicates that the vertical plane passing through 20-2FW-3 is offset by 5' from 24-2CL-56. Thus should a break occur in 20-2FW-3, it will pass by 24-2CL-56 with no contact.

Therefore, this interaction is excluded as an initiating event for this SDP.

Interaction 163 Interaction 163 is between 16-2FW-1 and 24-2CL-56 with the break occurring in Row F Column 12 elevation 695. The interaction is shown on Scientel Drawing A48. Breaks in 16-2FW-1 occur below the 715 grating for this interaction. The direction of whip will be along the plane generated by the axis of pipe where the break occurs and the plastic hinge point. As shown in plan view of A48, the section of piping below the 715 grating runs only in a vertical direction and would

EC 16270 Page 36 of 38 SCREENING OF PIPE WHIP INTERACTIONS FOR Prepared By: DJP SDP Date: 06/02/2010 not be expected to whip. The pipe will thrust up through the grating penetration (using the grating penetration as a guide) with minimal lateral movement. The minimal lateral movement would result in incidental (if any) contact with 24-2CL-56 whose centerline is 24" south.

Therefore, this interaction is excluded as an initiating event for this SDP.

Interaction 180 Interaction 180 is between 12-2MS-36 and 14-ZX-128 with the break occurring in Row E Column 13 elevation 715. The interaction is shown on Scientel Drawings A34a and A34b. The exclusion credited in ENG-ME-732 is a design basis consideration and will not be credited for this write up. The direction of whip will be along the plane generated by the axis of pipe where the break occurs and the plastic hinge point. As shown in plan view of A48, the section of piping above the 715 grating runs vertical direction and would not be expected to whip due to ceiling interferences. Breaks in the horizontal section will move away from the the ZX-14-128 line. The ZX-14-128 line runs parallel to the plane defined by the axis of the broken pipe and the plastic hinge point.

Therefore, this interaction is excluded as an initiating event for this SDP.

Interaction 198 Interaction 198 is between 16-2CD-10 and 10-2FP-1 with the break occurring in Row F Column 13 elevation 715. The interaction is shown on Scientel Drawing A44a and A44b. The direction of whip will be along the plane generated by the axis of pipe where the break occurs and the plastic hinge point. As shown in the SE isometric view of A44a, the vertical portion of piping above the 715' grating is 5'-6" from the fire protection line. The tee connection to 20-CD-10 is 16' north of this vertical section pipe. Considering a break at the 715' grating, the whip are radius is 18.36' from the hinge location. The line 10-2FP-2 is 21.67' from the hinge point.

,i

.. m-Z~-Z.

'L =7Z*, *'

lQ1'j

EC 16270 Page 37 of 38 SCREENING OF PIPE WHIP INTERACTIONS FOR Prepared By: DJP SDP Date: 06/02/2010 West View Assuming a hinge occurs at the grating, a break in the horizontal section will strike the G-line wall which is 98" from 16-2CD-1 0. The hypotenuse of the triangle will be 10'-10.5" and the adjacent leg will be 98". The piping will come to rest at a 41 degree angle from the grating (49 degree angle on the wall). The contact point will be 86" above the 715' grating (722.8'). From this contact point, 10-2FP-2 is 22.8 degrees from the G-line wall. The G-line wall will act an obstruction preventing contact between 16-2CD-10 and 10-2FP-2.

Therefore, this interaction is excluded as an initiating event for this SDP.

Interaction 199 Interaction 199 is between 20-2CD-10 and 10-2FP-1 with the break occurring in Row F Column 13 elevation 715. The interaction is shown on Scientel Drawing A55. The direction of whip will be along the plane generated by the axis of pipe where the break occurs and the plastic hinge point. As shown in south view and plan view of A55, all of the 20-2CD-10 piping near 10-2FP-1 is horizontal at an elevation of 725'-10.5". The 10-2FP-2 at an elevation of 728'-6". Should a break occur in an area close enough to reach the 10-2-FP-2 pipe, the 20-2CD-2 pipe would pass below 10-2FP-2.

Therefore, this interaction is excluded as an initiating event for this SDP.

EC 16270 Page 38 of 38 SCREENING OF PIPE WHIP INTERACTIONS FOR Prepared By: DJP SDP Date: 06/02/2010