Nozzle guide vane and method for forming such nozzle guide vane

摘要

A nozzle guide vane for a gas turbine engine includes an integrally formed angled nozzle with radially outer and inner platforms and an airfoil extending therebetween. An internal cooling air passage extends between the platforms. A cooling air outlet in the inner platform communicates with the air passage and opens to an inter stage cavity between stages of the engine and is formed as part of the nozzle with an outlet axis angled with respect to a radial direction of the engine. A transition area between a radially outwards facing part of the nozzle and an approximately linear outlet part including the outlet axis is formed as a curved conduit bend. An investment casting core member includes a cone-shaped part that defines the bend, a support part attached to the cone-shaped part and a cylindrical part which extends to the surface of the inner platform.