Design Analysis of the Selection of the Four Main Pipelines of the 1000MW Ultra Supercritical Unit

Pipelines for the main steam, hot sections of the reheat steam, cold sections of the reheat steam and the high pressure feed water are main constitutes of the power plant boiler. Material selection of the four main pipelines will have significant impact on the security and economy of the power plant operation. The pressure of the main steam of the 1000MW ultra supercritical unit in Tianjin SDIC Jinneng Electric Power CO.LTD is 27.56 MPa, and the temperature of the main steam is 605°C. It brings forward the high requirement of the mechanical characteristic and high temperature performance of the four main pipelines. Demonstration is processed considering the thermal stress, coefficient of the heat expansion, operation reliability and the economy, and the compositions of the four main pipeline material are selected.