DEVELOPMENT FOR BOILERS AND STEAM TURBINES OPERATING AT 700 ° C

In Europe development of boilers and steam turbines for plant operating at temperatures in excess of 700°C is being carried out within the EU supported AD700 project. This collaborative project involves all of the major European power plant manufacturers supported by utilities and research institutes. The first phase of the project began in 1998 and has been extended to run until the end of 2003. A second phase began in 2002 and runs until the end of 2005, although it is hoped this phase will also be extended to allow the continuation of longer term creep tests. The objective is the development of all technology necessary for the construction and operation of such plant. This paper describes the development of the high temperature materials technology essential to underpin the development of the AD700 power plant technology. It describes the factors influencing alloy design and selection and the scope and results of investigations on candidate alloys carried out within the project. It then goes on to describe the programme of full-scale prototype component manufacture which is currently in progress. These prototype components are being characterised through extensive long term testing programmes. The development of joining procedures for these materials is also described.