Experimental Research On Security And Economic Performance Of600MW Steam Turbine For Fenghe Power Plant

This paper stated the problems about security and thermal performance of600MW steam turbine after put into operation in Fenghe power plant. The problems include high heat rate in steam turbine and the serious deformation of inside cylinder. Investigation of similar problems and experience in handling domestic model unit was conducted. Combined with the latest technology, technology and material from East Steam Turbine Factory about supercritical units, as well as the successful transformation experiences from electric power industry, the comprehensive transformation test was conducted in Fenghe power plant#2Turbine.According to the theory analysis and experiment results, the most economic and practical steam seal DAS was selected to transform the traditional labyrinth seals that designed originally, and this makes the steam turbine can improve the thermal efficiency and run with high efficiency long time. And then, in view of the market situation that the actual load rate was not high and based on the actual test analysis, the optimization and improvement of high-profile sequence management and the degree of overlap optimization to improve on the original design is relatively conservative compound with steam way, so it tends to be more close to the nozzle governing mode. This will greatly reduce the valve throttling losses at low load, and the thermal efficiency of low load unit will be improved significantly under the premise of safety, At last, the problem of serious deformation in inside cylinder is analysised comprehensively, and the control and prevention measures on deformation are taken into practice. This will eliminate the cylinder deformation which will result in the metal damage and the risks of steam leakage in joint surface. So the safety performance and thermal efficiency of the unit will be improved.According to the safety and economic transformation test in#2Turbine, as well as the thermal test data and actual operating parameters of the unit from the Electric Power Test Centre, the major safety and economic indexs before and after transformation are contrasted reasonably. The effect and evaluation about this comprehensive transformation is given. This will lay a foundation and provide guidancefor the overhaul#1Turbine. The methods and technologies used in this project can be drew on for other steam turbine.