This report is the culmination of an effort initiated in 1976 by the IWGFR to evaluate detailed and simplified analysis methods for piping systems with particular emphasis on piping bends. The procedure was to collect from participating member IWGFR countries descriptions of tests and test results for piping systems or bends, to compile, evaluate, and issue a selected number of these problems for analysis, and to compile and make a preliminary evaluation of the analysis results. The Oak Ridge National Laboratory agreed to coordinate this activity, including compilation of the original problems and the final analyses results. Of the problem descriptions submitted three were selected to be used. These were issued in December 1977. As a follow-on activity, addenda were issued that provided additional data or corrections to the original problem statement. A variety of both detailed and simplified analysis solutions were obtained. A brief comparative assessment of the analyses is contained in this report. All solutions submitted have also been included in order to provide users of this report the information necessary to make their own comparisons or evaluations.