Evolution of Section XI of the ASME Boiler and Pressure Vessel Code

Abstract

This article will describe the development of Section XI from a pamphlet-sized document to the lengthy and complex set of requirements, interpretations, and Code Cases that it has become by the year 2000. Section XI began as a set of rules for inservice inspection of the primary pressure boundary system of nuclear power plants. It has evolved to include other aspects of maintaining the structural integrity of safety class pressure boundaries. These include procedures for component repair/replacement activities, analysis of revised and new plant operating conditions, and specialized provisions for nondestructive examination of components and piping. It has also increased in scope to cover other Section III construction: Class 2, Class 3 and containment structures. First, to provide a context for the discussions to follow, the differences in administration and enforcement between Section XI and the other Code Sections will be explained, including its dependence on the US Nuclear Regulatory Commission. The importance of interpretations and Code Cases then will be discussed. The development of general requirements and requirements for each class of structure will be traced. The movement of Section XI toward a new philosophy, risk-informed inspection, will also be discussed. Finally, an annotated bibliography of papers describing the philosophy and technical basis behind Section XI will be provided. [S0094-9930(00)01703-0]

Corrosion damage assessment and monitoring of large steel space structures

“…The SIFs also depend on the shape and size of cracks which are commonly irregular and even unknown before field inspection. ASME proposed a reference semi-elliptical crack having a depth a of 1/4 thickness t and a length c of 2 times depth a for steel components [18]. This type of crack is applied to both the structural members and structural joints in this study.…”

“…Since some uncertainties exist in the determination of K ISCC and the fracture due to stress corrosion cracking threats the safety of a structure, the necessary margin of safety should be taken into consideration in the assessment of stress corrosion cracking [18]. To this end, ASME [19,20] introduced a safety factor n b in stress corrosion cracking assessment of pressure vessels:…”

Nondestructive Detection of Tilted Planar Flaws on Back Surfaces Using Ultrasonic Wave Interference

“…The incident angle of the waves generated at a region other than the region C is too large to return to the probe which means the waves are missed. The offset of the probe location from top of the flaw denoted by 1 x in Fig. 9 (a) results in the side face reflection of the waves generated at the region C * (side reflection in Fig.…”

“…It is important to nondestructively detect flaws nucleated and developed on the inner surface of a structure, such as pressure vessels or pipes, from the outside of the structure to ensure their structural integrity (1) . The inspection schedule is based on the resolution limit of flaw detection and sizing of an nondestructive testing method used, as well as the prediction of flaw extension (2) .…”

Promoting the Regulatory Acceptance of Combined Ion and Neutron Irradiation for Material Degradation in Nuclear Reactors

“…Section XI of ASME BPVC focuses on the in-service inspection and maintenance of nuclear components. In 1970, Section XI published the first set of rules and standards for in-service inspection of LWR primary circuit components and piping [90,91]. Over the years, Section XI has expanded its scope to include other systems in LWRs, as well as gas-cooled and liquid metalcooled reactors [92].…”