As we have discussed here for years, “flanged joints” are usually MORE difficult to manage than are welded connections. However, somehow the rumor got started that flanged connections can be done by “Billy Joe Jim Bob.” Nothing could be further from the truth! And guess which connections most often leak? Yep, flanged connections. There are many reasons for this higher leak rate, but in most of my experiences, the flange leaked because it was NOT assembled correctly. Bottom line, our flange connections MUST have the same level of QC/QA as our welded connections.
In some of my more hazardous processes, some of which we classified as Category M Service (i.e., “Lethal Service”), our flanged connections had to meet the requirements of ASME PCC-1, specifically Section 14.2, Joint Assembly Records. In this article, I want to share this practice and explain the VALUE it brings to the assembling of our PRIMARY CONTAINMENT SYSTEM that utilizes FLANGED CONNECTIONS.