The Pre-1955 Era Until 1955, the ASME Boiler and Pressure Vessel Codes, and the ASME B31 Pressure Piping code provided rules of good design practice with quantitative criteria for pressure design. For example, quoting from ASME VIII Rules for the Construction of Unfired Pressure Vessels Section VIII A. S. M. E. Boiler Construction Code, 1927: […]
The evaluation of wall thinning corrosion in steel pipes is addressed in three ASME XI code cases: N-513, N-597, and N-806. I have no ambition here other than to summarize in a table the differences between these three code cases. A brief commentary follows the table. The brief commentary… Line A – While these are […]
Download/View as PDF Summary – This article assists engineers in selecting ASME XI options for the repair of ASME III nuclear components. In summary, the repair options in ASME XI are dispersed throughout Section XI and Code Cases, while, in contrast, the ASME PCC-2 repair standard (for non-safety related components) lists repair options in a […]
Before we tackle environmentally-assisted fatigue (EAF), what is fatigue? In ASME Boiler & Pressure Vessel Section III Division 1, Subsection NB (in short, ASME III NB) fatigue refers to the damage caused by systems and components as a result of cyclic loads. The qualification of the primary coolant system of light water reactors (ASME III […]
by Greg Hollinger and George Antaki One of the qualification requirements for a piping system is to keep the loads imparted by the piping on equipment nozzles within certain allowable limits. These loads consist of sets of three forces and three moments, for the various load combinations. There are basically two types of nozzle load limits: […]
Nuclear power plants are designed to be capable of a safe shut-down in case of a large design-basis tornado or hurricane. The magnitude of the postulated design-basis tornado or hurricane is such that there is less than 1 in 10 million chance (1E-7) per year and per reactor that it would be exceeded. This probability […]
It is normal for piping systems to exhibit steady pressure pulses. Most of the time these pulses are inconsequential; however, in a few cases they must be eliminated because they can affect the reliable operation of the system or they can cause a mechanical failure. Becht Engineering recently assisted a client in the evaluation of […]
Road Map of Regulatory Requirements General Design Criteria – The protection of nuclear power plants from the effects of tornadoes (or extreme winds from typhoons or hurricanes, depending on the locality) is required through 10CFR50 Appendix A, 10 CFR 50, Appendix A, General Design Criterion 2 which requires that structures, systems, and components (SSCs) important […]
Immediately following the Fukushima accident of March 11, 2011, the US Nuclear Regulatory Commission assembled a Near-Term Task Force to gather the lessons learned from the Fukushima Dai-Ichi accident. The Task Force compiled a set of “Recommendations for Enhancing Reactor Safety in the 21st Century.” The Recommendations were approved by the Commissioner and issued for […]
This article outlines the procedure to evaluate the fitness-for-service of corroded buried pipe, and explains what CC N-806 covers … and what it does not cover. What are the Damage Mechanisms in Metallic Buried Pipe? The inspection of a buried metallic pipe, after years of service, can reveal that the pipe has little if any […]
