Reducing Shrinkage Porosity in High-Performance Steel Castings: Case of an ASME B16.34 Gate Valve Body: Part 2—Simulation and Experimental Verification

Abstract

This study presents a systematic framework for reducing shrinkage porosity in high-performance steel castings, based on a simulation-driven optimisation process coupled to micro- and macrostructural evaluation of the castings. For the test case, the macro- and microstructural investigation of a Class 300 gate valve body, based on the ASME B16.34 standard and made from A216 WCB cast steel, using X-ray computed tomography and scanning electron microscopy, was presented in Part 1: Analysis, Techniques and Experimental Approach. This forms the basis for introducing appropriate design and process improvement measures to reduce shrinkage porosity severity levels, based on parameters that influence shrinkage porosity formation, particularly in terms of temperature gradient and solidification rate. Based on the improved design, and using a patternless sand mould manufacturing technology, a trial casting of the valve body was produced, showing a significant improvement in shrinkage porosity levels.