CPSES-200402114, Relief Request B-5 for the Second 10 Year Lsi Interval for Unit 1 from 10 CFR 50.55a for the Purpose of Invoking Code Case N-698, Design Stress Intensities and Yield Strength Values for Uns N06690 with a Minimum
| ML042800255 | |
| Person / Time | |
|---|---|
| Site: | Comanche Peak  |
| Issue date: | 09/29/2004 |
| From: | Madden F TXU Power |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| CPSES-200402114, TXX-04168 | |
| Download: ML042800255 (6) | |
Text
TXU v9 4
Power TXU Power Comanche Peak Steam Electric Station P. O. Box 1002 (E01)
Glen Rose, TX 76043 Tel: 254 897 5209 Fax: 254 897 6652 mike.blevins~txu.com Mike Blevins Senior Vice President &
Chief Nuclear Officer REF: 10 CFR 50.55a(3)(i)
CPSES-200402114 Log # TXX-04168 September 29, 2004 U. S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555
SUBJECT:
COMANCHE PEAK STEAM ELECTRIC STATION (CPSES)
DOCKET NO. 50-445 RELIEF REQUEST B-5 FOR THE SECOND 10 YEAR ISI INTERVAL FOR UNIT 1 FROM 10 CFR 50.55a FOR THE PURPOSE OF INVOKING CODE CASE N-698, "DESIGN STRESS INTENSITIES AND YIELD STRENGTH VALUES FOR UNS N06690 WITH A MINIMUM SPECIFIED YIELD STRENGTH OF 35 KSI (240 MPA), CLASS 1 COMPONENTS," FOR NEW CONSTRUCTION OF REPLACEMENT REACTOR VESSEL HEAD Gentlemen:
Pursuant to I OCFR50.55a(3)(i), TXU Generation Company LP (TXU Power) hereby requests NRC approval of the attached relief request. The relief from Section III of the 1989 Edition of the ASME Code is being requested for the fabrication of a replacement reactor vessel head for CPSES Unit 1. The details of the 10 CFR 50.55a request are attached.
TXU Power requests that the NRC authorize the use of ASME Code Case N-698, "Design Stress Intensities and Yield Strength Values for UNS N06690 With a Minimum Specified Yield Strength of 35 ksi (240 Mpa), Class I Components," as an alternative to certain requirements of NB-3112.4 for the new construction of the replacement reactor vessel head for CPSES Unit 1.
A member of the STARS (Strategic Teaming and Resource Sharing) Alliance Callaway
- Comanche Peak
- Diablo Canyon
- Palo Verde
- South Texas Project
- Wolf Creek PC)(41
TXX-041 68 Page 2 of 2 This communication contains no new licensing basis commitments regarding CPSES.
TXU Power requests approval of this relief request by March 31, 2005. The approval date was selected to allow procurement of long lead material that will be used in the fabrication of the replacement reactor vessel head. If you have any questions regarding this request, please contact Jack Hicks at (254) 897-6725.
Sincerely, TXU Generation Company LP By:
TXU Generation Management Company LLC, Its General Partner Mike Blevins Senior Vice President and Principal Nuclear Officer By:
Fred W. Madden Director, Regulatory Affairs JCH Attachment Enclosure c -
B. S. Mallet, Region IV W. D. Johnson, Region IV M. C. Thadani, NRR Resident Inspectors, CPSES Terry Parks, Chief Inspector, TDLR
Attachment to TXX-04168 Page 1 of 2 TXU POWER COMANCHE PEAK STEAM ELECTRIC STATION UNIT 1 SECOND TEN-YEAR INTERVAL ISI RELIEF REQUEST NO. B-5 PROPOSED USE OF CODE CASE N-698 I.
ASME System/Component(s) Affected:
Relief is requested for Reactor Pressure Vessel (RPV) closure heads manufactured to the requirements of Section III of 1989 Edition of the ASME Boiler and Pressure Vessel Code.
II.
Applicable Code Edition and Addenda
The replacement reactor vessel head manufactured to the requirements of Section III of the 1989 Edition of the ASME Code, Section NB-3112.4 requires the use of design stress intensity values for materials listed in the tables of Section II, Part D, Subpart 1.
Table 2B of Section II, Part D contains the design stress intensity values for Type Designation UNS N06690 for the SB-1 67 specification for Class 1 components.
III.
Proposed Subsequent Code Edition and Addenda and Code Case:
Pursuant to 10 CFR 50.55a(a)(3)(i), CPSES is requesting relief from the requirements of Section III of the ASME Code, 1989 Edition, Section NB-3112.4.
IV.
Reason for Request
Section II, Part B, Table 3 of the SB-1 67 specification provides an UNS N06690 yield strength that is dependent on manufactured condition. For seamless pipe and tube that are less than or equal to 5.0 inch outside diameter, Table 3 specifies a minimum yield strength of 30 kilopounds per square inch (ksi) for hot-worked or hot-worked annealed and 35 ksi for cold-worked annealed.
The UNS N06690 penetration tubes in the replacement reactor vessel closure head are manufactured using a hot-working process. Evaluation of the hot-worked UNS N06690 tubing has shown that a minimum yield strength of 35 ksi is inherent to the material.
Because of the large margin in the minimum yield strength in ASME Section II, Table 3, an ASME Code Case was needed to permit the use of higher design stress intensity values (23.3 ksi in lieu of 20 ksi) when the minimum yield strength is specified as 35 ksi for hot-worked UNS N06690 Class I components.
Attachment to TXX-04168 Page 2 of 2 TXU POWER COMANCHE PEAK STEAM ELECTRIC STATION UNIT 1 SECOND TEN-YEAR INTERVAL ISI RELIEF REQUEST NO. B-5 PROPOSED USE OF CODE CASE N-698 V.
Proposed Alternative:
ASME developed and approved ASME Code Case N-698 "Design Stress Intensities and Yield Strength Values for UNS N06690 with a Minimum Specified Yield Strength of 35 ksi, Class 1 ComponentsSection III, Division 1," permitting the use of higher stress intensities associated with 35 ksi minimum yield strength, hot-worked UNS N06690 SB-167. TXU Power is requesting that the design stress intensity values of Code Case N-698 be approved pursuant to 10 CFR 50.55a(a)(3)(i).
VI.
Basis of Usina the Code Case:
Pursuant to 10 CFR 50.55a(a)(3)(i), relief is requested on the basis that the proposed alternative provides an acceptable level of quality and safety.
VII.
Duration of Proposed Alternative:
This relief is requested for the Comanche Peak Steam Electric Station Unit 1.
VIII. Precedent:
- 1)
Farley Nuclear Plant (Reference SER dated May 26,2004, TAC Nos. MC1598 and MC1599.
ENCLOSURE TO TXX-04168 CODE CASE N-698
CASE N-698 CASES OF ASME BOILER AND PRESSURE VESSEL CODE Approval Date: November 18, 2003 See Numeric Index for expiration and any reaffirmation dates.
Case N-698 Design Stress Intensities and Yield Strength Values for UNS N06690 With a Minimum Specified Yield Strength of 35 ksi (240 MPa),
Class 1 ComponentsSection III, Division I Inquiry: Is it permissible in the construction of Class I components conforming to the requirements of Section III, Division 1, to use a nickel-chromium-iron UNS N06690 hot-worked and annealed condition with mini-mum yield strength of 35 ksi (240 MPa) otherwise conforming to material Specification SB-167?
Reply: It is the opinion of the Committee that the material specified in the Inquiry may be used in the construction of Class I components under the rules of Section III, Division 1, provided the following additional requirements are met.
(a) The design stress intensity and yield strength values shall be as shown in Table 1.
(b) The outer diameter is equal to or less than NPS 5 (DN 125).
TABLE 1 DESIGN STRESS INTENSITY AND YIELD STRENGTH VALUES Temperature Design Stress Intensity Yield Strength, F
Values, S,,, ksl (MPa) ksl (MPa) 100 23.3 (161.5) 35.0 (240.0) 200 23.3 (161.5) 31.6 (216.2) 300 23.3 (161.5) 29.8 (204.0) 400 23.3 (161.5) 28.7 (198.5) 500 23.3 (161.5) 27.8 (193.0) 600 23.3 (161.5) 27.6 (191.0) 700 23.3 (161.5) 27.6 (191.0) 800 23.3 (161.5) 27.6 (191.0)
(c) For external pressure the required thickness shall be determined in accordance with NB-3133 using Fig.
NFN-4 in Section II, Part D, Subpart 3.
(d) Welding procedures and performance qualifica-tion shall be in accordance with Section IX and this Code Case. The material shall be considered to be P-No. 43.
(e) This Case number shall be shown on the Data Report for the component and the marking and certifica-tion of the material.
1213 SUPP. 11-NC