Document: NUREG-0800
Document ID: d5452e7b-1e61-498b-9e3d-71073b3328ef
Document Type: srp
Title: LEAK-BEFORE-BREAK EVALUATION PROCEDURES
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0302/ML030280295.pdf
Revision Date: 2023-06
Chapter: 3
Section ID: 3.6.3
CFR Part: 
CFR Title: 

Content:
nditions may be omitted when these are shown to be small at OBE conditions. 3.6.3-5 g. The piping materials toughness (J-R curves) and tensile (stress strain curves) properties should be determined at temperatures near the upper range of normal plant operation. h. The specimen used to generate J-R curves should be large enough to provide crack extensions up to an amount consistent with J/T condi tion determined by analysis for the application. Because practical specimen size limitations exist, the ability to obtain the desired amount of experimental crack extension may be restricted. In this case, extrapolation techniques may be used as described in NUREG 1061, Volume 3, or in NUREG/CR-4575. Other techniques can be used if adequately justified. i. The stress-strain curves should be obtained over the range from the proportional limit to maximum load. j. Preferably, the materials tests should be conducted using archival material for the pipe being evaluated. If archival materia, is not available, plant specific or industry wide generic material data bases can be assembled and used to define the required material tensile and toughness properties. Test material should include base and weld metals. k. To provide an acceptable level of reliability, plant specific generic data bases must be reasonable lower bounds for compatible sets of material tensile and toughness properties associated with materials at the plant. To assure that the plant specific generic data base is adequate, a determination must be made to demonstrate that the generic data base represents the range of plant materials to be evaluated. This determination is based on a comparison of the plant material properties identified in (b.) above with those of the mater ials used to develop the generic data base. The number of material heats and weld procedures tested must be adequate to cover the strength and toughness range of the actual plant materials. Peason able lower bound tensile and toughness properties