Piping-Flexibility Analysis

Abstract

Abstract A steadily expanding literature bears testimony to the growing recognition of the importance of the problem of providing flexibility in piping and to the many difficulties besetting efforts at establishing a simple rational approach for its solution. This paper aims to outline the various phases of the problem, with particular emphasis on the phenomena of plastic flow and fatigue which distinguish the behavior of piping systems under thermal expansion from the ordinary room-temperature steady-state structural problem and lead to the concept of a limiting-stress range rather than an allowable stress as the criterion of the adequacy of a layout. In treating his subject, the author has sought to present the consensus of the Task Force on Flexibility charged with reformulating Chapter 3 of Section 6 of the Code for Pressure Piping. Their Proposed Rules are included as a focal point on which it is hoped broad discussion will center.