An Approximate Method for Determining the Limit Pressure of Piping Branch Junctions With d/D ≤ 0.5

A series of finite element computations have been conducted to establish the limit pressures for a range of piping branch junctions with d/D ≤ 0.5. The results have been compared with those obtained using existing assessment procedures. In general, the latter have been found to be conservative. An approximate method for calculating the limit pressure of a branch junction is proposed. This method supposes that the branch junction may be treated as a plain cylinder containing an axial through-wall crack. The crack length is dependent upon the type of branch junction. The limit pressure can be established using a modified form of a standard solution limit load solution for a cylinder containing an axial through-wall crack. This approximate method is shown to be valid for a wide range of junction geometries.