Document: NUREG-0800
Document ID: a4232dd4-7548-4c1c-9a51-16dc766f1087
Document Type: srp
Title: Revision 2 - March 2007
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0708/ML070800008.pdf
Revision Date: 2023-06
Chapter: 3
Section ID: 3
CFR Part: 
CFR Title: 

Content:
shifted; however, the initially determined intermediate break locations need not be changed unless one of the following conditions exists: (i) The dynamic effects from the new (as-built) intermediate break locations are not mitigated by the original pipe-whip restraints and jet shields. (ii) A change is necessary in pipe parameters such as major differences in pipe size, wall thickness, and routing. (2) With the exceptions of those portions of piping identified in 2A(ii), breaks in Class 2 and 3 piping (ASME Code, Section III) should be postulated at the following locations in those portions of each piping and branch run: (a) At terminal ends. (b) At intermediate locations selected by one of the following criteria: (i) At each pipe fitting (e.g., elbow, tee, cross, flange, and nonstandard fitting), welded attachment, and valve. Or, where the piping contains no fittings, welded attachments, or valves, at one location at each extreme of the piping run adjacent to the protective structure. (ii) At each location where stresses are calculated2 by the sum of Eqs. (9) and (10) in NC/ND-3653 of ASME Code, Section III, to exceed 0.8 times the sum of the stress limits given in NC/ND-3653. As a result of piping reanalysis, due to differences between the design configuration and the as-built configuration, the highest stress locations may be shifted; 4 Note that, in addition, breaks in nonseismic (i.e., non-Category I) piping should be taken into account as described in Section II.2.k, "Interaction of Other Piping with Category I Piping," of SRP Section 3.9.2. BTP 3-4-6 Revision 2 - March 2007 however, the initially determined intermediate break locations may be used unless redesign of the piping resulting in a change in pipe parameters (diameter, wall thickness, routing) is necessary, or the dynamic effects from the new (as-built) intermediate break locations are not mitigated by the original pipe-whip restraints and jet shields. (3) Breaks in seismically analyzed non-ASME