Creep analysis of pressurized circumferential pipe weldments—a review

Abstract

This paper reviews work related to the high-temperature creep analysis of pressurized circumferential pipe weldments. It is important to define the problem and thus metallurgical features correctly; the identification of material microstructural-property variations within the heat-affected zone (HAZ) and the failure modes of welds are briefly included, as well as in-service experience of pipe welds. Experimental methods, including model and full-size component testing, are summarized and examples of typical tests results are described. Material constitutive equations, which can be used in describing the creep deformation of and failure mechanisms in welds, are briefly described. Numerical modelling using finite element (FE) methods, covering a range of approaches and analyses, taking account of the effects of material properties, pipe geometry, weld dimensions and system loading, on the stresses and failure behaviour of pipe weldments, are summarized. Typical results are presented to illustrate the potential uses and limitations of the FE methods.