Turbomachinery blade or vane with a survivable machine datum

摘要

A turbine blade (18) for a gas turbine engine includes a machining datum and support tool interface (52). The datum and interface feature is a frustoconical depression residing in a blade outer shroud (36) and ideally aligned with an airfoil stacking line (40). The blade has a prefinished state in which the depression has a prefinished depth (d1) and a finished state in which the depression has a finished depth (d2). The finished depth (d2) is smaller than the prefinished depth (d1), but is nevertheless sufficient to act as a support feature during manufacturing operations. The utility of the depression, as both a datum and as a support feature, survives the original manufacturing operations so that the depression is useful for post-manufacturing inspection and repair. <IMAGE>