Analysis and verification of fracture mechanics criteria for a large monobloc high pressure vessel

Abstract

The explosive energy stored within an operating hot isostatic pressing vessel is considerable. Recently, National Forge designed and manufactured a large, forged monobloc vessel for this service. Since the heavy wall sections required raised concern as to rupture characteristics, a predictive structural analysis was performed utilizing several fracture mechanics models. For additional assurance, a series of physical tests were performed with test coupons from each end of the heat treated forging. These tests demonstrated that the fracture mechanics parameters assumed in the predictive study were conservative. This paper outlines both the predictive analysis and physical test program, and presents the results obtained for each.