ML042050317
| ML042050317 | |
| Person / Time | |
|---|---|
| Site: | Millstone  |
| Issue date: | 07/22/2004 |
| From: | Hartz L Dominion Nuclear Connecticut |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| 04-411 | |
| Download: ML042050317 (13) | |
Text
Dominion Nuclear Connecticut, Inc.
Mill\\ronc Power Stxion l h p e berry R o d
\\J tc r h rd, (Il 0638 5 July 22, 2004 U. S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, DC 20555 ominion Serial No.:
04-41 1 NL&OS/PRW Rev 4 Docket No.:
50-336 License No.:
DPR-65 DOMINION NUCLEAR CONNECTICUT, INC.
MILLSTONE POWER STATION, UNIT 2 10 CFR 50.55A RELIEF REQUEST RR-89-51 USE OF ANNULLED CODE CASE N-2 REQUIREMENTS FOR CORROSION-RESISTING STEEL, STEEL BARS, AND SHAPES, SECTION 111 Pursuant to 10 CFR 50.55a(a)(3)(i), Dominion Nuclear Connecticut, Inc. (DNC),
requests approval to use an alternative to the requirements of the American Society of Mechanical Engineers (ASME) Code, Section Ill, 1998 Edition with the 2000 Addenda, for the material requirements associated with the replacement of the Control Element Drive Mechanism (CEDM) housings as described in Attachment 1. These replacement housings are to be made of modified Type 403 stainless steel that will be fabricated to the requirements of ASME Code Case N-2 (Previously 1334-3), Requirements For Corrosion-Resisting Steel, Steel Bars, and Shapes, Section 111, provided in Attachment
- 2. DNC considers this alternative to provide an acceptable level of quality and safety and therefore meets the necessary requirements for approval under 10 CFR 50.55a(a) (3) (i).
The current ASME Code requirements for supplying a modified Type 403 stainless steel needed for a CEDM housing are in Code Case N-4-11 which is listed as an approved Section Ill Code Case in U. S. NRC Regulatory Guide 1.84, Rev. 32, June 2003. DNC recently determined that the material currently being used for fabrication of the CEDM housings does not meet the requirements of Code Case N-4-11. However, the material is able to meet the requirements of annulled Code Case N-2. Code Case N-2 is currently listed in Table 3, Annulled Unconditionally Approved Section Ill Code Cases, in the U. S. NRC Regulatory Guide 1.84, Rev. 32, June 2003.
To support reactor pressure vessel head (RPVH) replacement at the next refueling outage, fabrication of the CEDM housings, which has been in progress for several months, will continue.
In parallel, DNC has continued efforts to procure CEDM materials that meet the requirements of Code Case N-4-11. Due to the lead time required for CEDM fabrication, outage resource planning, and securing commitments for replacement power due to the extended outage required for RPVH replacement, DNC requests NRC complete its review of this application by August 12, 2004.
In a telephone conversation between Mr. Scott Wahl of the NRC and Mr. David Dodson of DNC on July 22, 2004, the need and schedule for this relief request were discussed.
Serial No. 04-41 1 Request RR-89-51, Use Of Annulled Code Case N-2 Page 2 If you should have any questions regarding this submittal, please contact Mr. Paul R.
Willoughby at (804) 273-3572.
Very truly yours, Leslie N. Hartz-Vice President - Nuclear Engineering Request RR-89-51, Use Of Annulled Code Case N-2 ASME Code Case N-2 (1334-3), Requirements For Corrosion-Resisting Steel, Steel Bars, and Shapes, Section Ill Commitments contained within this letter: None cc:
U. S. Nuclear Regulatory Commission Region I 475 Allendale Road King of Prussia, PA 19406-1415 Mr. V. Nerses Senior Project Manager U. S. Nuclear Regulatory Commission One White Flint North 1 1555 Rockville Pike Mail Stop 8C2 Rockville, MD 20852-2738 Mr. S. M. Schneider NRC Senior Resident Inspector Millstone Power Station
ATTACHMENT 1 USE OF ANNULLED CODE CASE N-2, REQUIREMENTS FOR CORROSION-RESISTING STEEL, STEEL BARS, AND SHAPES, SECTION 111 RELIEF REQUEST RR-89-51 DOMINION NUCLEAR CONNECTICUT, INC. (DNC)
MILLSTONE POWER STATION, UNIT 2
Serial No. 04-41 1 Request RR-89-51, Use Of Annulled Code Case N-2 Attachment I/
Page 1 of 6 Relief Request RR-89-51, Use Of Annulled Code Case N-2, Requirements For Corrosion-Resisting Steel, Steel Bars, and Shapes, Section 111 CONTENTS I
.O ASME CODE COMPONENTS AFFECTED....................................................
2 2.0 APPLICABLE CODE EDITION AND ADDENDA................................
............ 2 3.0 APPLICABLE CODE REQUIREMENTS........................................................
3 4.0 REASON FOR REQUEST..............................................................................
3 5.0 PROPOSED ALTERNATIVE AND BASIS FOR USE.....................................
3 6.0 DURATION OF THE PROPOSED ALTERNATIVE........................................
5 7.0 PRECEDENTS............................................................................................... 5 FIGURE 1 : TYPICAL CONTROL ELEMENT DRIVE HOUSING.........................
6
Serial No. 04-41 1 Request RR-89-51, Use Of Annulled Code Case N-2 Attachment I/ Page 2 of 6 Relief Reauest RR-89-51, Use Of Annulled Code Case N-2, Reauirements For Corrosion-Resistina Steel, Steel Bars. and Shapes, Section 111 Proposed Alternative In Accordance with 10 CFR 50.55a(a)(3)(i)
- Alternative Provides Acceptable Level of Quality and Safety -
1.O ASME CODE COMPONENTS AFFECTED:
Code Class:
1 System:
The 69 magnetic jack assembly Control Element Drive Mechanism (CEDM) housings at Millstone Power Station, Unit 2 (MPS 2) were originally fabricated in accordance with the American Society of Mechanical Engineers (ASME) Code Case 1337 (now Code Case N-4-11) and made of modified Type 403 stainless steel. These housings are pressure retaining, installed on nozzles in the Reactor Pressure Vessel Head (RPVH),
and encased in a non-pressure retaining shroud cover with bolted coil stacks that surround the drive mechanisms for the insertion and withdrawal of control rods for startup, operation, and shutdown of the reactor. A typical CEDM housing is shown in Figure 1. The specific component of the CEDM to which this request applies is identified on Figure 1 as the Motor Assembly Pressure Housing.
2.0 APPLICABLE CODE EDITION AND ADDENDA:
MPS 2 is currently in the third 10-year inservice inspection (ISI) interval, which started on April 1, 1999. The 1989 Edition of Section XI with No Addenda applies to the IS1 program and the 1998 Edition of Section XI with No Addenda is used as the primary ASME Code Edition for Section XI Repair/Replacement program activities. The original RPVH and CEDM housings met Section Ill, 1968 Edition through the Summer 1969 Addenda with Code Case 1337 used for the modified Type 403 stainless steel CEDM housing material. The replacement RPVH and CEDM housings will meet Section Ill, 1998 Edition with the 2000 Addenda and annulled Code Case N-2 for the modified Type 403 stainless steel housing material subject to the approval of this request.
Serial No. 04-41 1 Request RR-89-51, Use Of Annulled Code Case N-2 / Page 3 of 6 3.0 APPLICABLE CODE REQUIREMENTS:
CEDM housings need to exhibit certain material (i.e., strength and magnetic) properties that are not contained within the standard requirements for Type 403 stainless steel.
Because of the evolution of incorporating American Society for Testing and Materials (ASTM) specifications into Section II material specifications and the reduced need for CEDM material after early RPVH fabrication in the 1960s and 1970s, these requirements were never incorporated into Section II and thus Section Ill has no specified requirements at this time for this material. The only NRC approved Code requirements that exist today for supplying a modified Type 403 stainless steel needed for a CEDM housing are in Code Case N-4-11 which is listed as an approved Section Ill Code Case in U. S. NRC Regulatory Guide 1.84, Rev. 32, June 2003.
4.0 REASON FOR REQUEST:
DNC is submitting this request to allow the use of an Annulled Unconditionally Approved Section Ill Code Case, Code Case N-2, Requirements for Corrosion-Resistant Steel, Steel Bars, and Shapes, Section 111, shown in Attachment 2, for the following reasons:
0 There are no other NRC approved requirements other than Code Case N-4-11 to supply this material and only a limited number of suppliers are available that can meet the requirements of Code Case N-4-11.
Code Case N-2, although annulled, is unconditionally approved by the NRC and has always provided an acceptable level of quality and safety and continues to do so for plants that have used this Code Case for their RPVH CEDM housings.
5.0 PROPOSED ALTERNATIVE AND BASIS FOR USE:
The alternative in this request is to allow the use of annulled Code Case N-2 for the material requirements of the replacement CEDM housings at MPS 2. Modified Type 403 stainless steel material was used in the original design and fabrication of CEDM housings for Combustion Engineering Type Pressurized Water Reactors with two Section Ill Code Cases. Code Case 1334 (now Code Case N-2) and its revisions permitted use of modified Type 403 stainless steel in the annealed (40 ksi yield strength, 70 ksi tensile strength) and heat treated (80 ksi yield strength, 100 ksi tensile strength) conditions. Code Case 1337 (now N-4-11) and its revisions also permitted use of modified Type 403 stainless steel in the annealed (40 ksi yield strength, 70 ksi tensile strength) and heat treated (90 ksi yield strength, 110 ksi tensile strength) conditions. Code Cases 1334 and 1337 were originally approved on February 26, 1964. When the Nuclear Code Cases were renumbered in the 1977 Edition, these two Code Cases became Code Case N-2 (Previously 1334-3) and Code Case N-4-11 (Previously 1337-1 I), respectively.
Serial No. 04-41 1 Request RR-89-51, Use Of Annulled Code Case N-2 Attachment I/ Page 4 of 6 Code Case N-4-11 is still an active Section Ill Code Case and is listed as an acceptable Code Case in Regulatory Guide 1.84. Code Case N-2 was annulled in January 1981 in Supplement 4 of the 1980 Edition of the ASME Code. Most of the materials covered by Code Case N-2 were incorporated into Section Ill. However, the design stress intensity and material property values for the heat treated condition of modified Type 403 stainless steel in Code Case N-2 were never incorporated into Section 111. Code Case N-2 (1334-3) is identified in Regulatory Guide 1.84 as an Annulled Unconditionally Approved Section Ill Code Case.
The ASME is currently in the process of revising Code Case N-4-11 to add the heat treated condition of modified Type 403 stainless steel that was previously covered by the annulled Code Case N-2, but that revision may not be available to support the MPS 2 RPVH replacement schedule. The proposed Code Case revision adds the heat treatment and mechanical property requirements and design stress intensity values for heat treated modified Type 403 stainless steel that are defined in Code Case N-2. In the background statement for the proposed change ASME indicates that reinstating this second heat treatment condition will permit plants to design and build replacement CEDMs with the same requirements as the original components. Providing the second heat treated condition for the modified Type 403 stainless steel also provides an option to plants to select a more readily available material for the CEDM housings, provided all other design requirements are met.
The original MPS 2 CEDMs were fabricated using Code Case 1337 (now Code Case N-4-1 1) with a process that involved fabricating a CEDM housing by piercing a forging into a tubular housing shaped product form. There are limited suppliers at this time to provide this material. However, annulled Code Case N-2 can be used to supply the material requirements for the CEDM housings subject to the approval of this request in support of the upcoming MPS 2 spring 2005 RPVH replacement project. This Code Case will permit production of the CEDMs by forging a solid piece of material and machining that material into a tubular housing shaped product form that will meet the heat treated conditions described above as the proposed revision to Code Case N-4-11.
Although, the ASME has annulled Code Case N-2, it has been used for several other existing RPVH CEDM housings in earlier revisions as follows:
AN02 Code Case 1334-2 PALOVERDE2 Code Case 1334-3 0
ST. LUCIE 1 Code Case 1334-2 ST. LUClE2 Code Case 1334-3 WATERFORD3 Code Case 1334-2 Therefore, this request to use the existing Annulled Unconditionally Approved Section Ill Code Case N-2 meets the 10 CFR 50.55a(a)(3)(i) requirement as an alternative that provides an acceptable level of quality and safety.
Serial No. 04-41 1 Request RR-89-51, Use Of Annulled Code Case N-2 / Page 5 of 6 6.0 DURATION OF PROPOSED ALTERNATIVE:
Since this request centers on the replacement of the MPS 2 RPVH specific to the material requirements for the replacement CEDM housings, it is intended that approval of this request will apply for the life of the CEDM housings.
7.0 PRECEDENTS
A search of the documents within ADAMS has identified no precedents for the approval to use an Annulled Unconditionally Approved Section Ill Code Case. However, ASME has provided a Code Interpretation as follows:
Interpretation:
111-1-83-223
Subject:
Date Issued:
May 7,1984 Section Ill, Division 1, NA-1140/NCA-1140 Use of Code Editions, Addenda, and Cases (All Editions)
File:
N184-035, 111-1 Question:
May an organization utilize a Code Case, with the approval of the Owner and the jurisdictional authorities, after the annulment date of the Code Case?
Reply:
Yes, provided the annulment date of the Code Case is later than the Code of Record date for the plant.
DNC understands the NRC position on use of Code Interpretations, but this interpretation is shown to identify the ASMEs support for this type of request. This interpretation indicates that although no precedent has been found related to this request that, subject to the Staffs approval, this would be an acceptable alternative to the ASME.
Serial No. 04-41 1 Request RR-89-51, Use Of Annulled Code Case N-2 1 Page 6 of 6 FIGURE 1: TYPICAL CONTROL ELEMENT DRIVE HOUSING
ATTACHMENT 2 ASME CODE CASE N-2 (1334-3),
REQUIREMENTS FOR CORROSION-RESISTING STEEL, STEEL BARS, AND SHAPES, SECTION 111 DOMINION NUCLEAR CONNECTICUT, INC. (DNC)
MILLSTONE POWER STATION, UNIT 2
Serial No. 04-41 1 Request RR-89-51, Use Of Annulled Code Case N-2 / Page 1 of 3 I
CASES OF ASMB BOlldR AND PRE$SUtE VESSEL CODE Meettng of November 3,1978 Approved by Council, January 8, I979 27th Care rhdl sxpira on Jonuaty 8, I982 curlez, pwviourty annultad tw mffmd.
(2) Bur may bc utal ln only the follow-ing conditiom of hut trcihwnt:
(a) The arutcnlttc p d u ddl rocdvc a carbide duffon treatment whfch #MI con-sist or hdding the bur tors tuffldant length of t h e at mmpcntrse at which the chro-mium carbldor will p Into rolutfonmd then cooling in otlll air or I Ifquid medium at a rate mtffldsnt to pewt rnpredpttatbt~
(b) Tbe fgtitie p d u dull be an.
nsded or normrliPed i d tampered at 1260 F mMmum.
CASE N -2 (1 334-3) 3
Serial No. 04-41 1 Request RR-89-51, Use Of Annulled Code Case N-2 / Page 2 of 3 16,700 15,900 15,400 14,900 14,500 14,000 13.900 CASE (continued)
N-2 CASES OF ASME BOILER AND PRISSS1;RE VESSELCODE (1 334-3) 1 aa,300 aa,aoo ai.400 1
33,300 32.500 30,600 29.900 fanprature F I 309Sa up LO 100 20,000 20,000 20,000 20,000 650 18,800 18,300 750 18,000 17,500 600 i9,aoo NOTES:
- a. Specified minimum taodlo etrengrh. 75,000 p.4 SpsciIied aimhum yield strength at 0.2%
oflael; 30,000 poi.
- b. For sonin limlring factors rder 10 Tuble 1-3.0 Table II Design Strass Intensity, psi Annealed
[
Nornalissd end Temporod Temperature F 1 405e I 403.416 Sc 1 403,41Ob.416Sa {
414=
up 10 100 200 300 400 500 600 650 700 750 800 13;700 43,600 13,400 23.300 23,300 23,300 2f800 22,000 21,200 20,900 26700 19,900 19,000 29,500 28,500 27,100 38,300 38,300 37,400 36,100 34,900 34,400 a8,aoo 39;900 32,800 31,200 4
Serial No. 04-41 1 Request RR-89-51, Use Of Annulled Code Case N-2 / Page 3 of 3 200 27.0~0 z w o o ne,ioo 76.250 W,TSO 750 10.000 40,400 82.700 66,450 73,400 C A S I (contlnumd)
N =2 (1 334-3)
CASES 01' ASME BO11,BR AND PRESSIiRE VESSEL CODE 300 100 500 600 650 700 46,sso zamo 2i,sso ZI,.SSO PO,SSO 20.350 sa,oso zg,aoo 21.700 ~1,050 ~0,800 PO.SSO 36.8~0 35.6~0 34,700 aa,6so 8s.050 a2,900 78,750 71,360 69.450 67,860 66.5~0 6~.aoo 8a.000 BO,~OO 78,100 76,710 ?d.aso 74.060 800 850 PO0 950 1000 19,460 19,000 16,600 16,150 17,W
'20JS9 19,760 19,100 18.100 16.960 32,100 S1,bW 30.600 29,OW 47,110 64.460 a.100
~L.ZOO 58,050 64.2.00 7 2, s ~
71,100 6 a m o w o o 61,100 NOTES:
- 8. Speciflid minimum rmnaila atnngrhi 60.000 psi.
Specified minlmun ylsld mtren@thi 25,000 PI!.
- b. Specfliad mlnfmun cmrlla awn&
Specified minlmum yldd mken&i 80,000 C. Spscifiad minimum tenrih sLmn#th:
115,000 pa1; Serclfhd minimum yhld ohngthi 90.000 pai.
loovooo P d l Id.
414L a 09s 408' 408', 416' &
403*,4lOz 418s 414' 90.000 Table 111 Values o f Y h l d Strength I
I I
I I
1 I
100 ao,ooo 261000 40,000 80,ow 90,000
'Annealed ZTmpwed 5