WRC Bulletin 297 presents methods and data for treating two normally intersecting cylindrical shells, i.e., cylindrical nozzles radially attached to cylindrical vessels (shells). Stresses in both the nozzle and vessel can be determined, and the range of vessel diameter-to-thickness ratio covered is increased over that in Bulletin 107. The analytical method used was derived and developed by C.R. Steele on the basis of the thin shell theory.
Publication of these documents was sponsored by the WRC Pressure Vessel Research Council. WRC Bulletin 297 was published in 1984 and revised in 1987.
The sign convention indicated in PV Elite is according to WRC 107, and WRC 297 has a different sign convention rule.
Regarding to radial load, WRC 107 is + for compressive to cylinder, WRC 297 is + for tension to cylinder on the other hand. If pressure gives tension membrane stress and it combine radial force with algebraic summation. The plus or minus case for radial force with pressure gives different maximum results. For example, the pulling radial force is the severest because it generate tension membrane stress and it is same as one due to pressure.