ML19095A241

From kanterella
Jump to navigation Jump to search
Response to Request for Additional Information Fracture Toughness and the Potential for Lamellar Tearing of Steam Generator and Reactor Coolant Pump Supports
ML19095A241
Person / Time
Site: Surry  
Issue date: 05/15/1978
From: Stallings C
Virginia Electric & Power Co (VEPCO)
To: Case E, Reid R
Office of Nuclear Reactor Regulation
References
Download: ML19095A241 (5)
v • d • e


Text

-, i*, ~,---~n\\\\1/

-,-;*r**'i:1\\1*

1.--. i, ~i\\

TI'1'

'1*-1 I",,, II. \\

I.*\\ I

  • *,,
  • 1,1,-\\i'

- l:

~ \\ *- L '.._:,__':',, \\_'.. '--_-.....

VIRGINIA. ELECTRIC A.ND POWER COMPANY R:r:oHMOND, V:tRGXNXA 23261 May 15, 1978

    • '.t--i

-:.. - t~ ;

.. ~.. i";

.::~-2 -~* 1 Mr. Edson G. -* Case;,
  • Acting Director Office of Nuclear.Reactor Regulation Attn:

Mr~ Robert W *. Reid Serial No.~ 425Ai091477='/J POM/DLB: j.p-1

,-~

(.:)

-L

  • Operating Reactor Branch.No. 4 Division of Operating Reactors U.S. Nuclear Regulatory Commission Washington, DC* 20555
  • Docket Nos.

50-280 50-281 License Nos.

DPR-32 DPR-37

Dear Mr. Case:

This is in response to your letter of September-14, 1977 which requested-information on fracture toughness and the potential for lamellar

.tearing of steam generator and reactor*coolant pump supports.

Our previous submittal of December 6, 1977 (Serial No. 425/091477) provided a majority of the information requested~

As stated in that submittal since certain information was not readily.available our architect-engineer was requested to provide this information. *The architect-engineers review has _recently been completed~

The information obtained from their review is discussed below.*

I

.The_ f irSt. request* waS to provide themaximum developed and allow-able stresses for the steam.generator and main coolant pump supports under various load conditions.* AJ.tho_ugh sufficient data exists to confirm the adequacy.of the.support system design, the detailed information which develops the bases and loads_ for the reactor coolant pump supports*is not

.readily available,-~nd_ could be compiled only at considerable expense.

Due to the design of this support system, lamellar.tea:i:ing could not occur; therefore,. the.review of,detailed.design loads and stresses is not considered necessary. Thesesupports*are designedwithpin-ended connections at all niemb.er junctions. - There. a.re no welds at. heavy intersecting members which might be subject to.the potential. for lamellar tearing. _For this reason, we see no justification for. further investigation into this matter *

. The second request is for an evaluation of the fracture to_ughness of these supports. A review of the specifications and available material test reports for these supports was.performed and can be sununarized as

. follows:*

a. Insufficient material.test report data is available to assess fracture toughness on the*reactor coolant pump supports.*
b. *. The* steam genera tor support casting material is ASTM A352 GR. LC3 *. The highest nil ductility transition temperature
  • (NDTT} for which material test*_ reports* are available is below -20° F. This is more than-100 degrees lower than the minimum operating temperature of 83° F, cited* in VEPCO letter No. 425/091477.

This difference between the-operating.temperature and the NDTT ensures toughness and ductility of these steam generator support materials under all operating conditions.

---~~ ~-~---

-,i-*

e vrnmNIA ELECTn1c _AND PowEB CoMPANY To

~. Edson. G. Case*

c *. The lower ring swivel end coupling material is ASME SA 540. Fracture to_ughness of this material was found to* be acce]?table. *

d. Attachment 1 shows a summary of the NDTT values from available.test*results,*and Attachment 2 shows.the
  • specified NDTT requirements.

A comparison of available data shows that actual NDTT values are all considerably lower than required, thus providing the required fracture toughness.

Attachments cc: Mr. James P. O'Reilly, Director Office of:Inspection and Enforcement

.Region II 2

.:J_

i,

/

Attnchment l

  • Vepco letter Serial No. 425A/091477
  • I' p art Lower Ring Casting Lower Ring-Cylinder Tru.11nion l*bunts
  • Lower Ring Caps Lower Ring Cylinder End Clevises Upper RinEJ ATTACHMENT l STEAM GENE~ATOR SUPPORT CASTINGS - Jl2~2: Gr. L02 NDrT FROM 'rES'r REHULTS -

SURRY ll'<:2 S&W

.$&{

S

  • r* t*

N

.ioec1 1cn ion o.

D N

rmnnit o.

NUS-22 llf+./.8-FM-51A. 51B NUS-22 llli48-FM-

'51A. '51B NUS-22 llM~S-Frii-

  • 151A. 51B NUS-22 /

1M48-Fl.f...:

'51D NUS-22 11448-FM-51D NUS-22 llli48-J.iM-

'51D NUS-22 111.48-FM-

  • '5 J.D NUS-22 111.. 1.8-:FM-

'51D NUS-22 11448-FM-t;1D NUS-22 111.1~8-FM-51D NUS-28 11M,.8-F11.:..

I Erie Forge 0 d N

r er o.

F-3233-P-1 F-.3233-P-2 F-3233-P-3 F-3237-P-l*

-2 F-3237-P-3

-I..

F-3237-P-5

-6 F-3238-P-l

-16 F-3238-P-l 7

":"21,.

F-323~.-F:-l.

n

-o F-3~31:-P-9

-12.

F-3;:u~2-P-l See Note NDTT

°F I

0 = -110 M =

-110 0 <

-60 M <

-20 O<

-1.0 M<

-60 O= -110 M = -110 0 = -100*

H<

120 Q<

-60 M<

-1,0 0 = -100 M<.:.120 0 <

-60 M<

-/,n 0 = -100 M< -120 0 <

-60 M<

-//)

0 =

-80

  • 5lE

.. M =

.-8*1 NOTE:

l!DTT test in accordance with ASTH E-208 0 = o*.!ter third of the? wall (Sp.:cificatiok.reauirement.NDTT H =.middle third of the wo.11 (Specification ~cquircment,NDTT Erie Forge T t R t

es eoor N/A 7/16/68 10/31/68 N/A 4/16/68 11/22/68 4/16/68 10/31/68 4/16/68 11/22/68 11/29/68 I'

/

p t

o.r Upper Ring *(Cont)

ATTACfn.1ENT 1 - Cont STEAM GENERATOR SUPPORT CASTINGS -:._!.:3_2,. Gr. LC-~

NDTT FROM Tl~ST llf..SUL'l'S -

SURRY Jl.,.2 S&W S

  • f. t.

N

,,nec:t 1ca ion o.

NUS-28 NUS-28 S&W D

N raw1nrr lllil,.8-FM-51.E 11M~8-;FM-51F.

o.

Eric Forge 0 d N

r Ar

o.

F-J:2/~2-P-2.

F-3242-P-J Vepco letter Serial No. 425A/0914_7~

See Note NDTT °F

  • O< -60 H~ -~O..

0 = -50

. M ::: -50 Erie Foree, T t R es CJ?2!:!:

. 10/31/63 I I

N/A

\\

I -*

e

~epco letter Serial No.

425A/091477 ATIACHMENT 2

1.

Steam Generator Support, Upper Restraint Support, and Bearing Pad Material Drawing Requirement ASTM A352, Gr. LC3 11448-FM-SlF NDTT (ASTM E208) = 0 F for the outer third of the wall;

+40 F for the middle third of the wall The properties of thts material are similar to the properties of the castings in Attachment 1.

2.

Steam Generator Support Lower Ring Leg Assembly and Details Specification Material Requirement NUS-280 ASTM A237, Class E (Forging}

NDTT (ASTM E208) = +20 F 3,

Steam Gener?tor Support Lower Ring Leg Assembly and Details Specification Material Drawing NUS-198 Vascomax 300 CVM and 350 CVM 11448-FM-518 No specific fracture toughness requirements.

(

Retrieved from "https://kanterella.com/w/index.php?title=ML19095A241&oldid=4933375"