Value/impact assessment of jet impingement loads and pipe-to-pipe impact damage

Abstract

To account for effects that might result from a loss-of-coolant accidents (LOCA), nuclear power plant designers have been required to analyze the effects of double-ended guillotine breaks (DEGB) in high-energy piping. The US Nuclear Regulatory Commission (NRC), through its Standard Review Plan (SRP), requires that plant designers follow certain prescribed methods and criteria in the estimation of dynamic effects associated with the postulated rupture of piping. The work reported in this NUREG is intended to provide the basis for NRC decisions on adopting revisions to parts of the SRP 3.6.2 entitled Determination of Rupture Locations and Dynamic Effects Associated with the Postulated Rupture of Piping.'' The revisions considered in this work evaluated updated prescriptions for calculating jet impingement forces on critical systems and the requirement to consider pipe-whip damage to a new population of pipes. In accordance with the procedures documented in NUREG/CR-3586 entitled A Handbook for Value-Impact Assessment,'' this report found indication that substantial costs and occupational radiation exposure would result from the proposed action without substantially reducing the risks to public health and safety. 21 refs., 2 figs., 18 tabs.