The Past and the Future of Horizontal Steam Generators

Abstract

The design concept of horizontal steam generators (SG), applied at WWER NPPs, differs from the design concept of vertical SGs applied at NPPs of the most western countries. Nowadays all over the world there are 270 SGs in operation at Units with WWER-400 and WWER-1000, and some Units are under construction. Operation experience showed that the horizontal SGs have a number of advantages from the viewpoint of both reliability, and safety. The report deals with consideration of the design concept of SGs applied at WWER NPPs as compared to vertical SGs. The effect of SG design on thermal efficiency and engineering and economic indices is analysed. The ways of improving the efficiency of horizontal SGs are described. The selection of tubing material and a possibility of assuring the tubing reliable operation throughout the design service life are considered. The operation experience is analyzed and the ways of solution of the occurred problems are shown. In the future, the operational performance of SGs for WWER NPP will be improved as a result of theoretical and experimental studies. A description is given for the ways of design development on the basis of operation experience. It is shown that the basic design solutions for the horizontal SGs can be used for new Units of power to 1600 MW.