Fabricated Turbine Rotors - Advanced Steam Turbines. Report No. COAL R265 DTI/Pub URN 04/1798, DTI, UK

Abstract:

<p>This document is a report for the project titled 'Fabricated Turbine Rotors - Advanced Steam Turbines'.</p> <p>An investigation has been made into the possibility of welding together 10%Cr and 3.5%NiCrMoV rotor material in order to produce the next generation steam turbines operating above 570&deg;C.</p> <p>Following a comprehensive modelling programme and complementary testing and examination by Siemens Power Generation (SPG) and the University of Cambridge, a welding procedure was developed and successful plate and small diameter welds were made between sections of 3.5%NiCrMoV and 10Cr material. Mechanical and metallurgical assessment of these welds showed that the weldment properties matched the requirements of the original parent material.</p> <p>Following the success of the initial welds, a large-scale weld has been manufactured using the established materials and procedures to fully validate the developed welding procedure. This weld has been subjected to non-destructive examination (NDE) followed by extensive mechanical and metallurgical testing. The results confirm that the large scale weldment properties matched the requirements of the original parent materials and thereby satisfy the objectives of the project.</p> This report is divided into the following sections: <ol> <li>Summary</li> <li>Introduction</li> <li>Objectives of the Project</li> <li>Technical Challenges</li> <li>Development Procedures</li> <li>University of Cambridge Modelling</li> <li>Development Welding Trials</li> <li>Full-Scale Welding Trial</li> <li>Conclusions</li> <li>Figures 1 to 9</li> </ol>

Author(s):

Hutchinson, J., Conroy, R. & Stalker, R.