Research on the Manufacturing of Steam Turbine Blade by Using Investment Casting Technology

This paper presents the results of research on the manufacturing of steam turbine blade by using investment casting technology. Metal forming technology with precision casting process or investment casting is the right technology for the manufacture of turbine blades, because it can produce casting products that has advantages in size and shape accuracy, surface finish and the ability to produce thin casting, which the usually foundry can not be done. The purpose of this research is to produce a good quality of the casting products as an effort to reduce import dependency of steam turbine blade and to be the alternative way of making steam turbine blades in Indonesia, in addition to the machining process. Based on the experimentation trial implemented on casting products of stainless steel 304, the result indicates that the injection temperature for the wax NF-411 and optimal nozzle in hydraulic injection machine are 64°C and 30°C, injection pressure 1.75 MPa and injection time 9 seconds. The best casting induction furnace achieved at temperature 1,620°C as for to the number of ceramic mould coat which is good to be obtained at 7 layers. The testing results show that: (1) the chemical composition is appropriate with standard, (2) the hardness is 160 HB, (3) the shrinkage is 2.83%.