Document: NRC Regulatory Guide
Document ID: 2704425a-c58a-45c4-93ab-8761721c3e7a
Document Type: regulatory_guide
Title: Evaluation of Reactor Pressure Vessels with Charpy Upper-Shelf Energy Less Than 50 Ft-Lb
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML0037/ML003740038.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.161
CFR Part: 
CFR Title: 

Content:
= [56.927 + 264.21 (a/t') - 838.6 (aft')2 + 750.88 (aft')2] ksiv"in. A-3 These results were also used in developing the unified Equation 13 for K, where the constant CR and the nomalizhd crack depth, at', are used as dependent vaiables. A least-square statistical fit was performed to obtain Equation 13. The czoss-product term, (CRXa/'), was also used in developing this fit, in addition to the polynomial terms in aW and CIL A-4 L. 0 iz 4- 30 ..... 60 ..... 9 ..... 0 Transient Time (Minutes) Figure A-i: Transient Tcmperatxnc H-istory at Crack Tip for Scrvce Levels A and B. A-5 CD- t"o O 0 an PWR Vessel, Service Levels A and 8 11R=86.5 In, t =0.156 In, t'8.6 I,. a/t*=0.25 l O0"/hr Cooldown for 150 Minutes •o--o Temperature at the Crack-Tip 0 ""150 0 -. Co 0 U) .-D1 PWR, Level A&B, Generic Welds. t.L0. 156 In C R3,1486.5in, t'=8.6 In, Axial Crack, a/V'0.25 Io 00*F/hr Cooldown, Critical Time =45 Minutes o---o : J (Applied Load, Criteria No. 1) Crack Extension = 0.1 In. +-+ : J-R Curve (CVN - 41 ft-1b) O-'-- : J-R Curve (CVN - 40 ff-ib) *" * J-R Curve (CVN = 39 ft-lb) 6 . 3b 60 90 120 150 Transient Time (Minutes) Figure A-2: J-Applied mnd J-R Curve History at Crack Tip for Service Levels A and B at a Crack Extensio of 0.1 inch. A-6 0 C o PWR. Level A&B, Generic Welds, f.O=.l 56 In S R=86.51n, f=8.6 In.. Axial Crack, a/t=0.25 j o00F/hr Cooldown. Critical Time =45 Minutes o--o : J (pplied Load. Criteria No. 1) ICe---1.. J-% Curve (CVt=41 ft-lb, T=5.00TF) I ,-- .J (Applied Load, Criteria No. 2) i . .. ... .......... ,.,,. "0.1 " 0.2 Crack Extension 0.4 (in) 0.5 0.6 Figure A-3: Acceptable Upper-Shelf Ewrgy in a PWR Vessel for Service Levels A and B. A-7 N CE) -o T C 4 C .0 0 | , I ; i I 0.1 0.2 Crack 0.3 Extension 0.4 0.5 0.6 (in) Figure A4: Safdy Margin Evaluation in a PWR Vessel for Service Lcve C. A-S 0 V Un C4 0 0 .0 CdA T -o i'5 * PWR Vessel, Level C, High Toughness Plate R1=90 In, t=9 In, Axial Crack, ao0.9 In T=550-250[exp(-.1 tm)]°F, tm=20 minutes : J (Appliled