CVGRAPH Version 5.0 Released

CVGRAPH Version 5.0 is a complete upgrade from the previous version of CVGRAPH 4.1 (a DOS-based program) to make the program fully compatible with Windows 95/98.  The program has been redesigned with a completely new graphical user interface and includes a number of new features.  

In addition to the new user interface, a significant technical enhancement has also been added -  the option to fit Charpy data to the asymmetric hyperbolic tangent equation of the form:

Cv = A + B*TANH(T - To)/(DT + C)

   where:

   D = the degree of asymmetry (in temperature) in the Charpy curve.

This asymmetric fitting function provides a better fit to data that is not symmetric in the upper shelf and lower shelf regions of the test data.  Of course, CVGRAPH 5.0 retains the previous version's symmetric fitting function as well.

CVGRAPH 5.0 was designed to facilitate the data input and management process.  Data input is greatly simplified by the ability to enter Charpy data directly via the Windows clipboard (e.g., from CVN test data in Excel spreadsheets).

Other refinements/enhancements include:

The ability to plot up to five data sets on the same plot;

The ability to customize the plot range and selection of major and minor tics to be displayed;

CVGRAPH 5.0 permits data conversion and plotting in both English or metric units.

Special upgrade pricing is available to currently licensed users of CVGRAPH 4.1 (or earlier versions).  Contact Bill Server at (925) 577-6496 or by E-mail for more information.

RPV Material Property Handbooks

Since 1993 ATI has assisted nuclear plants to improve the documentation of essential reactor vessel material properties.  Recently, this has included the development of comprehensive material property handbooks to be used as quick reference tools for responsive utility engineers.

The RPV Material Property Handbook organizes and reports essential vessel materials data, with clear explanations of the data sources and the bases for derived materials parameters, such as Adjusted Reference Temperatures.  Such handbooks facilitate the plant owner's embrittlement management and life extension planning activities.

The typical RPV handbook documents fabrication history, offers a detailed review of chemistry test results (eliminating duplicates), calculates best estimate chemistries, and reviews available surveillance test results.  Appropriate chemistry factors based on Reg. Guide 1.99, Revision 2, methods are also derived.  Finally, an analysis is performed to confirm the Adjusted Reference Temperature values and identify the limiting vessel materials  (with respect to embrittlement).  Differences with previously reported values are noted so that licensed values can be updated, as appropriate.

In several cases, the process of generating the handbook helped to resolve ambiguities in RPV materials data that had existed since construction.

Additional information about ATI's services for reactor vessel material property documentation is available from Bill Server at (925) 577-6496 or by E-mail.