ML20099K307

Rev 2 to Design Rept, SCE - San Onofre SG Manway & Handhole Stud/Studhole Repair Evaluation Units 2 & 3

ML20099K307
Person / Time
Site:	San Onofre
Issue date:	05/13/1992
From:	Bell B, Sodergren J ABB COMBUSTION ENGINEERING NUCLEAR FUEL (FORMERLY, ASEA BROWN BOVERI, INC.
To:
Shared Package
ML20099K305	List: ML20099K304 ML20099K307
References
CR-9448-CSE92-1, CR-9448-CSE92-1106R2, CSE-92-212, NUDOCS 9208260031
Download: ML20099K307 (18)

Text

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REPORT: _13 Pacres APPENDICES: O Paces OTHER ATTACHMENTS: O Paces DESIGN REPORT FOR SOUTHERN CALIFORNI A EDISON - SAN ONOFRE STEAM GENERATOR MANWAY AND HANDliOLE STUD / STUD'iOLE REPAIR EVALUATION UNITS 2 AND 3 CR-9448-CSE92-110G, REV. 2 This document is the pronerty of ABB/ Combustion En;ineering, Chattanooga, Tennes ee, and is to be used orJy for the purpows of the greement with ABB/CE pursuant to which it is fumished.

PREPARED BY: O A d6" - #

DATE: NW9L VERIFICATION STATUS COMPLETE The safety-Related design information contained in this -

document has been verified tog "e correct by means of Design Review using checklist (s) 7 of QAM-101.

Name JC- Signature -

Cate 6 / 4 L Independent Reviewer /

APPROVED BY: . DATE: 5 -O ~ 7 7-

_.s .s aege m ABB COMBUSTION ENGINEERING CH ATTANOOGA. TENNESSEE 9200260031 920824 PDR ADGCK 0S000361 P PDR

___ _ _m . .. .

V.

CR-9448-CSE92-1106, REV. 2 Page 2 Of 18 RECORD OF REVISIONS PARAGRAPH (s) PREPARED INDEPENDENT APPROVED NUMSER DATE INVOLVED BY REVIEWER BY J.H.

B.A. Bell K.E. Coe Sodergren 0 3/5/92 Original Issue 2/27/92 2/27/92 2/27/92 J.H.

B.A. Bell K.E. Cce Sodergren 1 5/5/92 2.0, 4.4 5/5/92 5/8/92 5/8/92 B A. 8ess- Mc '% s J.M. W , v s

• d# 1( h. A b 2 5/13/92 4.2, 4.4 g/fy/tL 8/ 7/4 % 5~lt 'n.

CSE-92-212

CR-9448-CSE92-1106, REV. 2 Page 3 of 18 TABLE OF CONTENTS PAGE

1.0 INTRODUCTION

4

'2.0

SUMMARY

OF RESULTS 5

3.0 REFERENCES

6 4.0 ANALYSIS 7 4.1 Stud Thread Engagement 7 4.1.1 Primary Manway 9 4.1.2 Secondary Manway 9 4.1.3 Secondary Handhole 9 4.2 Reinforcement with Helicoil Inserts 9 4.2.1 Primary' Manway 9 4.2.2 Secondary Manway 10 4.2.3 Secondary Handhole 11 4.3 Shear Strength of Helicoil/ Stud Arrangement 12 4.3.1 Primary Manway 13 4.3.2 Secondary Manway 14 4.3.3 Secondary Handhole 15 4.4 Compatibility of Stud /Helicoil/

Manway/Handhole Materials 16 CSE-92-212

~

CR-9448-CSE92-Il06, PEV. 2 Page 4 of 18

1.0 INTRODUCTION

The required stud thread engagement is determined for the SCE San Onofre Units 2 and 3 steam generator manway and handhole closures. The application of helicoilinserts for stud hole thread repair is established for these closures.

Design conditions are evaluated in accordance with the requirements of the ASME Boiler and Pressure Vessel Code,Section III.

be d

CSE-92-212 O

L_L______-_--_ - - - - - _ - _ _ _ _ _ . . _ _ _ _ _ _ _ _ _ _ _ _ _ _ - _ _ _ _ _ _ _ _ - _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ - _ _ _ - _ _ _ _ _ _ - _

5 CR-9448-CSE92-1106, REV. 2 Page 5 of- 18 2.0 -

SUMMARY

OF RESULTS The stud minimum required thread engagement is 1.5" or 12 full threads for the primary manway,1.25" or 10 full thr: ads for the secondary manway and 1.25" or 10 full threads for the secondary handhole. When the helicoil insens are installed, the stud minimum required thread engagement is greater than the above i values Application of the following helicoilinserts requires a larger diameter hole which _

meets the reinforcement requirements of the ASME Code.

1.5"-8 Pitch x 2.5" Nominal Length Helicoil Insert for Primary and Secondary Manways.

1.0"-8 Pitch x 1.5" Nominal Length Helicoil Insert for Secondary Handhole.

The shear stress in the threaded insert is less than the allowable stress for the maximum design stud load. It is concluded that the helicoil insert meets the ASME Code requirements and may be installed in any of the closure stud holes.

Also, there is no limit on the number of helicoil inserts that can be installed in each enclosure.

No compatibility problems are known to exist with the use of a stainless steel _

helicoil insert installed with a low alloy steel stud and studhole for the manways and handhole. This statement applies to both corrosion and thermal expansion points of consideration.

CSE-92-212

CR-9448-CSE92-1106, REV. 2 Page 6 of 18

3.0 REFERENCES

1. " Analytical Repon for Southern California Edison San Onofre Unit No. 2 Steam Generator", CENC-1272, dated September,1976.

2. " Analytical Report for Southern California Edison San Onofre Unit No. 3 Steam Generator", CENC-1298, dated September,1977.

3. AShiE Boiler and Pressure Vessel Code,Section III for Nuclear Vessels, 1971 Edition, and Addenda through Summer 1971.

4. Bulletin 913B, " Heli-coil 8-pitch Insert", Heli-Coil Products, A Black &

Decker Company, Danbury, CT 06810.

5. Bulletin 1000, " Heli-Coil Screw Thread Inserts Inch Series Design and Production hianual", Heli-Coil Products, A Black & Decker Company, Danbury, CT 06810.

6. "hiachine Design", by Shigley, J.E., hicGraw-Hill Book Co., Inc.,1956.

CSE-92-212

-w , .._

= - u- m~ - w , m m -w +

CR-9448 CSE92-1106, REV. 2 Page 7 of 18 4.0 ANALYSIS .

From References 1 and 2, the following table summarizes the specifics for each closure opening using the worst case design conditions from Units 2 and 3 steam generators.

TABLE 4.1 Manway and Handhole Stud Details Prirnary Secondary Seccadary:

De.scription l Manway Manway Handhole No. of Studs 20 16 10 l Threads Specitication i 1/2 8N-2A 1 1/2-8N 2A 1-8UNC 2A Stud Material SA-540 B-24 CL.3 SA 540 B-24 CL.3 SA-t93 B-7 S. (stud) KS! 34.8 36.6 28.t Base Material SA 533 Gr.B CL.1 SA 508 CL.2 SA-508 CL.1 S. (base) KSI - 26.7 26.7 17.9 d (pitch dia.) in. 1.4188 1.4188 0.9188 F (preload/ stud) kips 48.75 36.5 18.5 Design Temp. 'F 650 560 560 4.1 Stud Thread Engagement The average thread shear stress for the stud screw is given by the following formula:

t = '. Equa cion 1 n ch l CSE-92-212 L

CR 9448 CSE92-1106, REV. 2 Page 8 of 18 Rearranging this equation results in a formula for minimum length of thread engagement or:

2 h= Equa cion 2 Where, d = Pitch Diameter, in.

F = Prelcad/ Stud, kips. ,

T = .6 S, (Paragraph NB-3227.2 of References 3 for Pure Shear) 3, = Design Stress Intensicy ior Incernal Thread Ma cerial, KSI,1. 0, Base Material in Table 4.1 _

B Equation 1 or 2 is more conservative than the one in Reference 6, page 185, for averaec thread shearing stress of the internal thread material.

This is due to the pitch diameter in equations 1 and 2 being less than the major diameter of the thread in the equation from Reference 6.

Substituting into equation 2 resuits in the following minimum thmd length engagements for each c!nsure opening using the design conditions in Table 4.1 CSE-92-212

/ ,

r CR 9448 CSE92-1106, REV. 2 Page 9 of 18 4

4.1.1 Primary Manway h= (4 ~

.ns8) 26. E " l'37 i"*

For primary manway stud use 1.5" minimum or 12 full threads.

4.1.2 SecondaIy_Maruny 2 ~$

1

-h = -

= 1.o2 in.

, ,41 8 (.6 26.7)

For secondary manway stud use 1.25" minimum or 10 full threads.

4.1.3 Secotdary Handhole h= 2( .

(g,g1g8) . 6 x 17 . 9 )

For secondary handhole stud use 1.25" minimum or 10 full threads.

4.2 Reinforcement with Helicoil Inserts -

The manway and handhole reinforcement areas are calculated for the helicoilinserts in both Units 2 and 3 per Paragraph NB 3334 of Reference

3. Using the worst case closure openings from Units 2 and 3 steam generators, results in the following reinforc: ment areas.

4.2.1 Primary Manway From page A 41 of Reference 2, CSE-92 212

y,-,,,,, .. - - -- ~ ~ ~ ~ ~ ~ ~ ~ ' ~~

CR-9448-CSE921106, REV. 2 Page 10 of 18 A3 = M.764 in.a A2 " 8*327 IU*

A 3n;uc,a a 3.125 (1.625) =

5. 07 8 in.2 ( w/helicoilin ser c)

Asy,gurty = A +A 2 -A sn~?me 3

= 39.7 64 + 8. 3 27 - 5. 07 8

= 4 3. 013 in. 2 > Amvim = 31. 9 06 in. 2 The reinforcement area requirement is met based on using a 1 1/2" helicoil insert with a tapped hole diameter of 1.625".

4.2.2 Seondary Manway From page A-48 of Reference 2, A1 = 1.596 in.2 A = 31. 56 2 in. ' + Old Studhole (i . e. 4. 5 in. 2) = 36.062 in.2 2

A3 = 10. 37 0 in. 2 A, = 4. 3 4 6 in. 2 Asneuxs = 3. 0 (1.625) =

4. 87 5 ia ' (w/helicoil inser t)

CSE 92-212

A CR 9448 CSE921106, REV. 2 Page 11 of 18 l

An.,gw u = A g *A g

• A, + As - Am nou

= 1. 596 + 36. 06 2 + 10. 37 0 + 4. 346 - 4. 87 5

= 47. 49 9 in.2 > Ancurac = 4 3 . 4 5 2 in . 8 The reinforcement area require..nent is_ met based on using a 1 1/2" helicoil insert with a tapped hole diameter of 1.625".

4.2.3 Secondarv Handhole From page A-55 of Reference 2, Ag = 0. 0171 in. 8 A2 =

12. 8 31 in.2 + Old Seudhole (i . e. 2. 2 5 in.8) = 15. 0 81 in. 8 A3 = 2. 6 41 in. 2 --

A, = 1. 5 51 in. a Amruou = 2. 2 5 (1.12 5) = 2 'i31 in. a l'

A,y,,wu = A + A,

• A, + A, - A megou g

= 0. 0171 + 15. 0 81 + 2. 6 41 + 1. 5 51 - 2. 5 31 CSE 92 212

1 CR.9448 CSE921106 REV. 2 Page 12 of 18

= 16 . 7 5 9 in . 3 > A,g.;m = 15 . 3 2 8 in . 2 The reinforcement area requirement is met based on using a l' helicoil insert with a tap,atd hole diameter of 1.125" 4.3 - Shear Strencth of Helicoil/ Stud Arrangement The helicoil specifications are as follows:

1 Material: SA-479, Type 304 or 302 (Reference 5)  ;

S.: 16.8 ksi @ 560 'F (Table I 1.2 of Reference 3) 16.2 ksi @ 650 'F (Table I 1.2 of Reference 3)

Size: 1 1/2" 8N x 21/2" engagement (Reference 4) 1"-8N x 1 1/2" engagement (Reference 5)

The tensile stress area of the stud design, A, is based on the thread root or section of least diameter, do , and is given by the following formula:

~

A= ",d Equa cion 3 The maximum design stud load, F, is:

F = A x S., (for stud ma terial) Equa tion 4 The shear stress in the helicoil, r, is:

,e x= Equa tion 5

[

l' CSE 92-212 l

l l

l

...-r._ . _ , , . - - . . , . - - . _ . ,__ . - - - ~ , - - _ . - - _ - . _ _ . _ - , - - _ . , _ , . _ - . . - _ , . . . , . . . . . . . . , , . , - . _ , _., _ -..-.,. .... - -.. m -.-,-- . , . - - - , - . , .

F CR 9448 CSE921106, REV. 2 Page 13 of 18 Where, d = Pitch Diamecer of Th:eads h, = Minimum Thread Engagemene of Helicoil Equation 5 is the same as Equation 1 and is also more conservative than the one in Reference 6, page 185, for reasons previously mentioned. _

Substituting into Equations 3,4 and 5, results in the following helicoil shear stresses for the respective closure opening.

4.3.1 Primary Manway Tensile Stress Area a = " (1 31)* 1.348 in.:

Maximum Design Stud Load at 650 'F F = (1.348)(34.8) = 46.91 kips Shear Stress in Helicoil

, , 2(46.91) n (1.4188) (2.25)

Where:

d = 1.4188" h,, = 2.25' (Reference 5 for 1 1/2" Helicoil Insert)

Use 1 1/2 8 x L i" long insert with 18 minimum free" coils.

" Free coils are counted 90* from the tang in the uninstalled (free) condition (Reference 4).

5 CSE-92 212

i CR-9448 CSE921106, REV. 2 Page 14 of 18 .

t = 9 . 3 5 ksi < . 6 S ' or . 6 (16.2) = 9.72 ksi "Per paragraph NB-3227.2 ef Reference 3 for Pure Shear The shear stress allowable is satisfied for the Maximum Design Stud ,

Load. ,

4.3.2 S.c.condary Manway Tensile Stress Area

• I1'31I = 1. 34 8 in. 2 A=

4 Maximum Design Stud Load at 560 'F F = (1. 34 8) (36.6) = 4 9 . 3 4 kips Shear Stress in Helicoil y , 2(49.34) x (1.4168) (2.25)

Where; d = 1.4188" h,, = 2.25" (Reference 5 for i 1/2" Helicoil insert)

Use 1 1/2 8 x 2.5" long insert with 18 minimum free

• coils

" Free coils are counted 90* irom the tang in the uninstalled (free) condition (Reference 4).

CSE 92-212 y- ~ w op a q g-og+_. m., , -_m,-,yg o.y7-r -t--t y

CR 9448 CSE921106, REV. 2 Page 15 of 18

= 9. 64 ksi < .6 S, er . 6 (16. 9) = 10. 0 8 ksi The shear stress allowable is satisfied for the Maximum Design Stud Load.

4.3.3 Secondary Handhole

~

Tensile Stress Area A. n (.837 5): = 0. 5 51 in. 2 4

Maximum Design Stud Load at 560 'F F = (0. 551) (28.1) = 15.48 kips Shear Stress in Helicoil

,, 2(15.48) n(0.9188) (1.5)

Where; d = 0.9188"

h. = 1.50" (Reference 5 for 1" Helicoil insen)

Use 1"-8 x 1.5" long insert with 10.2 minimum free" coil

" Free coils are counted 90' from the tang in the uninstalled (free) condition (Reference 5).

T = 7 .15 ksi < . 6 S, or . 6 - (16. 8) = 10. 0 8 ksi The shear stress allowable is satisfied for the Maximum Design Stud Load, CSE 92-212

-A

CR-9448 CSE921106, REV. 2 Pr.ge 16 of 18 4.4 Compalibility of Stud /Helicoil/Manway/Handhole Materials The helicoil material is stainless steel, type 304 or 302 with an ASME designation of SA 479. The stud is a high strength low alloy steel bolting material either in SA 540, B 24, CL 3 or SA 193, B 7 designation. The j manway/handhole studhole is also low alloy steel materialin either SA-533, Gr B, CL 1; SA 508, CL 2: or SA 508, CL 1 designation.

The heli coil insert is manufactured from a corrosion resistant alloy (stainless steel), This alloy will not degrade from corrosion in the reactor containment environment as long as the material does not come in contact with known chemicals (chlorides, etc.) that can potentially initiate a corrosion mechanism.

The presence of stainless steel installed in a bolted joint with low alloy steel will not increase the propensity for corrosion of low alloy in this particular environment.

From a thermal expansion standpoint, only the primary manway opening was examined, since the application of the nominal coefficients of thermal expansion to its respective dimensions would give the most conservative results, I

d 1

4 l

CSE 92 212 4

o, w e-y ** MyYT'M-->-g-yw 'wiymr--qq=-q- k g' 'm ei mm'm 9 e p--m- g wyv y F-**" - * ' *-'

CR 9448-CSE92 Il06, REV. 2 Page 17 of 13 From Table I 5.0 of Reference 3, Table 4.2 lists the properties for the respective primary manway materials.

TABLE 4.2 Thermal Expansion Coef6cients for Primary Mansvay J

Mean Coef6cient of Thermal Expansion Rate Expansion @ 650 F (in/in)

Description Material a (104 in/in/'F) (a x (650-70))

Stud SA-540, B-24, CL 3 7.41 0.004298 Helicoil Insert SA-479, Type 302 or 304 9.61 0.005574 Studhole SA-533, Gr B, CL 1 7.90 0.004582 i Figure 4.1 shows a cross section view of the stud /helicoilinsert/studhole material arrangement with the applicable " worst case" dimensions.

FIGURE 4.1 Cross Sectional View s7m lsrgse

is.ns?

anuPT

/ s a

,,S ~ 4 p ?,/!,3 ' '*w.. ';;

.v ,

v

.. . , ., a r .

i

=!

1. ,  % nl. n V, '

i

i, ]/'

}i l \ h l r~s w . a i,, ' % 6 .

.>y t ,

l 1

',w, i, 2 .

i: ,o = a . o z s . n

/ ,, N.

l N."

s

• CSE-92-212 f

1

CR 9448 CSE92.I106, REV. 2 Page 18 of 18 Prr the above figure, the following dimensions at room temperature,70

'i , are:

r., = 0.6733 in. (max.) i r = 0.8125 in. (min.)

w=ru r,,, = 0.1392 in. (min.)  !

h,,,, = .750 p = .750(.125) = 0.0938 in. (min.)

w, = 0.115 in."

h = 0.092 in.*

Since the dimensions on the cross sectional view of the helicoil insert are 0.092 in by 0.115 in., there is clearance between the helicoil insert and the stud and studhole thread surfaces at room temperature,70 'F. When the strangement in Figure 4.1 is increased in temperature to 650 'F, all the surfaces expand. The new dimensions at 650 *F are:

rjeug = 0.6733 (1.004298) = 0. 6 7 6 2 in. (max . )

rb 3, = 0. 8125 (1 .004582) = 0. 808 8 in. (min. )

v' = tb., - t eud = 0.13 26 in. (min. )

004502 hdin = 0. 09 3 8 (1 - a .004298) a 0.0934 in. (min.)

v,3 9 0.115(1.005574) = 0.1156 in. < 0.13 26 in = v$n h,v 0. 09 2 (1. 005 57 4 ) = 0.0925 in. < 0. 09 34 in. = han At.650 'F, there is still clearance between the helicoil insert and the stud and studhole thread surfaces. Therefore, no stnictural problem is present with the thermal expansion of the different materials.

" Actual as-measured values from a typical helicoil (1.5" size).

CSE 92-212 r w w ,, -

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