Cracks in steam turbine components

Steam turbine components that operate under conditions of high temperatures and/or stresses develop cracks. The tests carried out during residual-life assessment attempt to detect these cracks, so that proper actions can be taken. As the only manufacturer of large steam turbines in India, Bharat Heavy Electricals Ltd. is the major agency carrying out this work. However, as the analysis of RLA data of numerous USSR and KWU design turbines shows, most of the components have certain specific locations, depending on design and unit rating, where cracks occur. The authors suggest that it may be more productive and prudent to concentrate on these locations during site tests.