Document: NUREG-0800
Document ID: 8d8c874b-f1ef-4884-8228-654f526c0ce4
Document Type: srp
Title: PUMP FLYWHEEL INTEGRITY (PWR)
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0520/ML052070445.pdf
Revision Date: 2023-06
Chapter: 5
Section ID: 5.4.1.1
CFR Part: 
CFR Title: 

Content:
ould fail. Overspeed of the pump rotor assembly during a transient increases both the potential for failure and the kinetic energy of the flywheel. The safety consequences of flywheel failure could be significant because of possible damage to the reactor coolant system, the containment, or the engineered safety features. Application of this criteria ensures that there will be an extremely low probability of missiles from the flywheels resulting in consequences to the reactor coolant system pressure boundary, containment, and engineered safety features. 5.4.1.1-7 DRAFT Rev. 2 - April 1996 III. REVIEW PROCEDURES The reviewer will select and emphasize material from the procedures described below, as may be appropriate for a particular case. For each area of review, the following review procedure is followed: 1. Materials Selection The materials selection, including the procedures to minimize flaws and improve mechanical properties described by the applicant, are reviewed and compared with the requirements of subsection II.1 of this SRP Section. If it is a new material not used in prior licensing cases, the materials selection is reviewed and evaluated to establish its acceptability. Based on past evaluations, the following materials are suitable for pump flywheels provided that they meet all the criteria listed in subsection II.1 and II.2 of this SRP section: ASME SA-533-B Class 1, ASME SA-508 Class 2, ASME SA-508 Class 3, and ASME SA-516 Grade 65 (Ref 2) . These material specifications are listed in 34 35 the Code, Section II.36 2. Fracture Toughness The fracture toughness properties of the flywheel materials, including test data where applicable, are reviewed and compared with the requirements of subsection II.2 of this SRP section. Two alternative methods for deriving the fracture toughness of the flywheel materials are acceptable. 1) The value of the critical or reference stress 37 38 intensity factor is based on fracture mechanics testing., while the 2) The use of