STATOR VANE ASSEMBLY FOR TURBINE AND METHOD FOR FORMING ASSEMBLY

PROBLEM TO BE SOLVED: To provide a stator vane assembly and method of forming the assembly capable of eliminating or minimizing any distortion in the welds and providing a high strength joint. SOLUTION: The turbine stator vane segments having inner and outer bands and a stator vane extending between both bands are welded along adjoining edges from outer sides of both bands by electron beam welding. The adjoining edges of high temperature gas passage sides of the inner and outer bands are chamfered, are welded by means of TIG, mechanical worked, and thereby, a smooth continuous gas pass surface is formed. An aft hook of each segment is cut down, and thereby, inset surfaces are disposed on a radically outwardly directed flange and a flange extending from the radial direction to an axial direction. A filler piece having a main formed corresponding to the shape of gaps between the inset surfaces of the radial direction flange is welded with the radial direction flange by means of electron beam welding. A weld material is disposed in the gaps between the tongue of the filler piece and the inset surfaces of the radial direction extending flange, and is welded by means of TIG, and then the aft hook welding is completed.