Published in August of 1984, Welding Research Council (WRC) 297 attempts to extend the existing analysis tools for the evaluation of stresses in cylinder-to-cylinder intersections. WRC 297 differs from the widely-used WRC 107 primarily in that WRC 297 is designed for larger d/D ratios (up to 0.5). WRC 297 also computes stresses in the nozzle and the vessel, whereas WRC 107 only computes stresses in the vessel.
The CAESAR II WRC 297 module provides input tabs for vessel data, nozzle data, and imposed loads. WRC 297 supports one set of loads. You can enter the loads in either global CAESAR II convention or in the local WRC 297 coordinate system. If the global CAESAR II convention is selected, vessel and nozzle direction cosines must be present in order to convert the loads into the local WRC 297 convention as discussed in the WRC 297 bulletin.
The CAESAR II version of WRC 297 adds the pressure component of the stress using Lame’s equations, multiplied by the stress intensification factors found in ASME Section VIII, Div. 2, Table AD-560.7. The pressure stress calculation is not a part of the WRC 297 bulletin but is added here for your convenience.
CAESAR II also uses, through Input > Piping, the nozzle flexibility calculations described in WRC 297. For more information,
see Piping Input Reference.
After you provide the necessary input, CAESAR II calculates the stress components at the four locations on the vessel around the nozzle and also the corresponding locations on the nozzle. Stresses are calculated on both the outer and inner surfaces (upper and lower). These stress components are resolved into stress intensities at these 16 points around the connection. For more information on the allowable limits for these stresses and output processing, see WRC Bulletin 107.