Creep crack growth was introduced over 25 years ago as a fracture mechanics discipline. However, its application to engineering structures remains rare.
With funding provided by the Edison Electric Institute (EEI), WRC's Pressure Vessel Research Council (PVRC) initiated a program to facilitate implementation of creep crack growth methods in electric power plant maintenance strategies. The objective envisioned required incorporation of an accepted creep crack growth methodology in a post-construction flaw evaluation Codes. The goal has now been reached with the inclusion of methods in an API/ASME Fitness-for-Service Standard. An important element of the plan was to establish a network of internationally recognized investigators to work on the project and to use that group to report state of the art information as the basis for developing the proposed practice.
The group provided a definitive evaluation of currently used major creep crack growth methods/parameters, identifying the strengths and weaknesses of each considering issues appropriate for use in the power plant applications to be covered. This WRC Bulletin covers the procedures evaluated by Prof. Kamran Nikbin and his colleagues at Imperial College in London. It is one of a set prepared to detail the methods, preserve the data used and comprehensively explain the concepts of the participants and others.
The results of calculations of incremental growth are assembled on a FAD diagram. If a point on the FAD predicted for crack growth to a service time lies on or outside the FAD failure contour, then the life of the component is limited to the time corresponding to such service. If this time is less than the current operating time, the component should be repaired or retired.
| File Size : | 1
file
, 5.7 MB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 103 |
| Published : | 2006 |
