Evaluation and Improvements to a Mechanical Engineering Capstone Designed Autoclave System for Use in High Temperature Aqueous Environments

Servohydraulic load frames have been used to perform fatigue testing for decades. Additions to these frames, such as high temperature furnaces and torsional stressing, have allowed for increased research opportunities. An area of additional needed fatigue research is the nuclear industry. Crack growth analysis in an aqueous reactor environment with high temperature and pressure is needed. Specimens in this environment provide fatigue data in a corrosive environment when subjected to these conditions for long tests. To gather this data, a new experimental system is required. One such system was designed by a senior capstone group at the University of Idaho. The system was developed from a modified autoclave with a servo-hydraulic frame attached to it. The system was designed to be attached to a fluid control panel that would circulate pressurized water into the autoclave. This system could be heated and would fully simulate a reactor environment. Several issues emerged in the building of this system. The control and functionality was limited, causing the need for future improvements. Improving the cooling jacket, seals, fluid control, and data collection process was performed. Several iterations of these processes were attempted. Preliminary testing of these new devices was performed to show the progress and results. Data was collected in both air and water as the working fluid filling the autoclave chamber. Several heated and pressurized tests were performed as well. Problems were encountered upon several stages of the initial testing. While promising results were gathered, future improvements are still needed. Safety features as well as additional system cooling will need to be applied. Once completed, this system can perform fatigue testing in a heated and pressurized aqueous environment simulating that of a reactor.masters, M.S., Mechanical Engineering -- University of Idaho - College of Graduate Studies, 2020-0