Tube Damage Mechanism and Analysis in Feed Water Heaters

Abstract

Steam power plants are responsible for the production of most electric in the world. A small increase in the thermal efficiency of the plant means a large saving of fuel consumption. Therefore every effort is made to improve the efficiency of the cycle on which steam power plants operate. One of the major elements that increase the efficiency of the power plants is feed water heater.The study has been carried out to investigating the causes of tube failure of the high pressure feed water heaters in an electric power stations. Specimens of the failed tubes were examined and photographs of the microstructure of the tube material were taken. Mechanical properties and chemical composition of the tube material were also examined. Comparison between the failed tube and new tube was made. The results of the laboratory test showed that the main reason for the tube failure is the OD (outside diameter) erosion. This effect is very clear especially in desuperheating zone