Document: NUREG-0800
Document ID: b3748a15-3b80-4626-a0a5-eb9f270739ad
Document Type: srp
Title: DETERMINATION OF RUPTURE LOCATIONS AND DYNAMIC EFFECTS ASSOCIATED
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0523/ML052340555.pdf
Revision Date: 2023-06
Chapter: 3
Section ID: 3.6.2
CFR Part: 
CFR Title: 

Content:
pture In Areas Other Than Containment Penetration (1) With the exceptions of those portions of piping identified in B.1.b, breaks in Class 1 piping (ASME Code, Section III) should be postulated at the following locations in each piping and branch run: 3.6.2-12 Rev. 1 - July 1981 (a) At terminal ends.2 (b) At intermediate locations where the maximum stress ranges as calculated by Eq. (10) and either (12) or (13) exceeds 2.4 Sm. (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 locations4 based on Eq. (10) should be selected. If the piping run has only one change or no change of direction, only one intermediate location should be postulated. As a result of piping reanalysis, the highest stress locations may be 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 Mb) or Cc) above. (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 signifi- cantly 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. 4Extremities of piping runs that connect to structures, components (e.g., vessels, pumps, valves), or pipe anchors that act as rigid constraints to piping motion and thermal expansion. A branch connection to a main piping run is a terminal end of the branch run, except where the branch run is classified as part of a main run in the stress analysis and is shown to have a significant effect on the main run behavior. In piping runs which are maintained pressurized during normal plant conditions