Abstract: A mechanical arrangement for the inner rail retention of a singlet nozzle to provide protection against catastrophic nozzle failures is disclosed.

Abstract: First stage nozzle airfoils have internal core profiles substantially in accordance with Cartesian coordinate values of X, Y and Z set forth in Table I wherein X, Y and Z values are in inches. The X and Y values are distances which, when connected by smooth continuing arcs, define internal core profile sections at each radial distance Z. The profile sections at each distance Z are joined smoothly to one another to form a complete internal core profile. The X, Y and Z distances may be scalable as a function of the same constant or number to provide a scaled-up or scaled-down internal core profile. The nominal internal core profile given by the X, Y and Z distances lies within an envelope of ±0.030 inches in directions normal to any internal core surface location.

Abstract: Arcuate seal layers conforming with one another are disposed between inner retainer segments and inner rails of nozzle segments of a gas turbine. The layers are secured to the aft axial face of the segments and project radially outwardly to seal against the forward axial faces of the rails. The rear axial faces of the rails have chordal seals for sealing against the forward axial faces of the support rings. The seal layers have radial cuts misaligned with one another in an axial direction to preclude leakage flows through gaps formed by the cuts. Arcuate spacers are staggered circumferentially with the arcuate retainer segments whereby an intermediate pressure plenum is formed between the finger seals and chordal seals.