Document: NUREG-0800
Document ID: 645cc743-c9e4-428c-b05d-ead2517eb3fa
Document Type: srp
Title: DETERMINATION OF RUPTURE LOCATIONS AND DYNAMIC EFFECTS
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0520/ML052070315.pdf
Revision Date: 2023-06
Chapter: 3
Section ID: 3.6.2
CFR Part: 
CFR Title: 

Content:
tresses under those loads and conditions thereof for which level A and level B stress limits 5 have been specified in the System's Design Specification, including an OBE event as calculated by Eq. (9) and (10), Paragraph NC/ND-3652 of the ASME Code, Section III. Select two locations with at least 10% difference in stress, or if stresses differ by less than 6 10%, two locations separated by a change of direction of the pipe run. 3.6.2-17 DRAFT Rev. 2 - April 1996 (c) At intermediate locations where the cumulative usage factor exceeds 0.1. (d) If two intermediate locations cannot be determined by (b) and (c) above, two highest stress locations based on Eq. (10) should be 5 selected. If the piping run has only one change or no change of direction, only one intermediate location should be postulated.71 As a result of piping reanalysis, the highest stress locations may be 72 shifted; however, the initially determined intermediate break locations need not be changed unless one of the following conditions exist: (i) Maximum stress ranges or cumulative usage factors exceed the threshold levels in (b) or (c) above.The dynamic effects from the new (as-built) intermediate break locations are not mitigated by the original pipe-whip restraints and jet shields.73 (ii) A change is required in pipe parameters such as major differences in pipe size, wall thickness, and routing. (iii) Breaks at the new highest stress locations are significantly apart from the original locations and result in consequences to safety- related systems requiring additional safety protection. In such conditions, the newly determined highest stress locations should be the intermediate break locations.74 (2) With the exceptions of those portions of piping identified in B.1.b, 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