Appendix O “Determining Joint Assembly Bolt Load’ was added in the 2010 version of ASME PCC-1 “Guidelines for Pressure Boundary Bolted Joint Assembly”. It outlines a method of calculating an appropriate assembly load for pressure vessel and piping bolted joints. However, the possible uses and scope of the appendix go well beyond only the selection of assembly bolt load. For example, the method can be applied to gasket selection or assembly method selection. The calculations in the appendix can easily be applied to quantify when certain technology can be employed and when it shouldn’t and can also be used as a tool to contribute to the overall gasket selection or assembly method selection process. In fact, once an understanding of the basic behavior of the joint is obtained, then the method can be applied to the full life-cycle of the joint, including use as a tool to determine the root cause of leakage. Basic procedures for performing these types of assessments and some pertinent examples are outlined in this paper.
