COOLED TURBINE BLADE AND METHOD FOR ITS MANUFACTURE Russian patent published in 1997 - IPC

FIELD: foundry; may be used in manufacture of cast cooled blades of high-temperature gas turbines by the method of directed crystallization. SUBSTANCE: method includes successive production of main and additional cores, pattern, mold, melting of metal, pouring the melt into mold and directed crystallization of casting with subsequent removal of ceramics. For this purpose main core is located in intermediate pattern mold, a layer of wear-resistant pattern material is applied to obtain intermediate pattern with holes. Then additional core is made in the second core mold whose die is provided with pins for hole formation. After that final pattern is made in respective mold. Turbine cooled blade manufactured by this method has hollow body with channels and hollows. Wall of body consists of two or several profiles with holes to pass cooling air which are connected with channels and having non-coincidence axes located at an angle of 30-90 deg to profile tangent planes. Profiles are interconnected by stiffening members, for instance, pins. Design of cooled blade manufactured by the offered method and having penetration cooling of internal hollows whose efficiency equals or exceeds 0.6 allows to increase the gas temperature at turbine inlet up to 2200 K and reduction of cooling air flow rate by 15-20%, and increase of blade service life in engines of new generation by 2-4 times. Method enables manufacture of cast in block single crystal cooled blades whose walls consist of several profiles with no welded or soldered joints, and all channels and holes are produced in the course of directed crystallization. EFFECT: higher efficiency. 3 cl, 4 dwg