PRODUCTION OF AIR COOLED TYPE GAS TURBINE BLADE

摘要

PURPOSE:To cast the gas turbine blade having the cooling holes of high cooling effect by using the glass tubes of rough surfaces as cores. CONSTITUTION:Part or the whole of the surfaces of the glass tubes 6 used as cores for providing cooling holes 5 of the turbine blade are roughly formed such as to satin skin form. The glass tubes 6 are mounted to the metal mold for pattern and a wax pattern 9 is made. The wax pattern 9 is coated with casting material to make a mold. After the turbine blade is cast by using this mold, it is dipped in a hot alkali solution to let the glass tubes 6 remained in the casting elute. By this method, the air cooled type gas turbine blade formed with the cooling holes 5 having suitable roughness on the inside surfaces is perfected. The inside surface shapes of these cooling holes 5 result in increased heat transfer area and increased disturbance of the velocity of flow of the cooling air 7, thereby improving the cooling effect of the blade.