Current State and Trends in the Design and Operation of Water-Cooled Condensers of Steam Turbines for Thermal and Nuclear Power Stations (Review)

Аннотация

A review and analysis are presented of the available foreign publications on the modern methods of design, manufacture, design calculation, and operation of water-cooled condensers for large steam turbines used in Russia and abroad. A list of the world’s leading manufacturers of condensers is presented. The adopted alternative arrangements of condensers concerning the turbine centerline and available condenser design styles are examined. The condensers for turbines manufactured by General Electric and the Leningrad Metal Works (LMZ) are compared by their design characteristics and performance indices. The arrangements of tube bundles used in designing and upgrading condensers in Russia and abroad are presented. Information is given on construction materials of condenser tubes and tube sheets as well as on the methods for tube-to-tube sheet attachment. Data on air removal equipment of the condensers are presented. The basic lines of evolution of steam jet ejectors, water-ring pumps, and hybrid air removal systems are considered. The methods of condenser heat-transfer surface cleaning adopted in Russia and abroad are compared. The data on the number of failures and the basic causes of these failure are presented. The procedures for replacement of tubes during repair or modernization of condensers and the symptoms used to determine the necessity of tube replacement are described. Information derived from the authors' investigations and a review of American publications on the potential for heat transfer enhancement in the condensers through the use of shaped tubes is given. The condenser design methods and standards applicable in Russia and abroad are assessed. The lines of improvement in the design of condensers for modern steam turbines of thermal and nuclear power stations are outlined.