【国外标准】 Standard Practice for Surveillance Testing of High-Temperature Nuclear Component Materials

4.1 The practice contained herein can be used as a basis for establishing conditions for the safe operation of critical structural components. The practices provide for general plant assessment and verification that materials continue meet design criteria and may in addition be of use for asset protection or life extension. The test specimens and procedures presented in this practice are for guidance when establishing a surveillance program.4.2 This practice for high-temperature materials surveillance programs is used when nuclear reactor component materials are monitored by specimen testing. Periodic testing is performed through the service life of the components to assess changes in selected material properties that are caused by neutron irradiation, thermal effects, chemical reactions, and mechanical stress. The properties of interest are those used as design criteria for the respective nuclear components or well correlated to said criteria (see 5.1.6). The need for surveillance arises from the need to assess predictions of aging material performance to ensure adequate component performance.4.3 This practice describes specimens and procedures required for the surveillance of multiple components. A surveillance program for a particular component will not necessarily require all test types described herein.1.1 This practice covers procedures for surveillance program design and specimen testing to establish changes occurring in the mechanical properties of ferrous and nickel-based materials due to irradiation and thermal effects of nuclear component metallic materials used for high-temperature structural applications above 370 °C (700 °F). This should include consideration of gamma heating. This practice currently only applies to an initial program based on initial estimates of design life of components.1.2 This practice was developed for non-light-water moderated nuclear power reactors.1.3 This practice does not provide specific procedures for extending surveillance programs beyond their original design lifetimes.1.4 This practice does not consider in-situ monitoring techniques but may provide insights into the proper periodicity and design of such.1.5 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.