Abstract: An abradable honeycomb is integrally formed in a turbine nozzle sealing flange for engagement with a bucket angel wing to reduce the leakage of air into the turbine's hot gas path. The honeycomb is integrally formed in a turbine nozzle sealing flange using a sinker EDM method to directly sink the honeycomb into the sealing flange itself, so that the honeycomb is an integral part of the flange. For repair, an entirely new honeycomb flange can be made and welded or brazed on to the turbine nozzle.

Abstract: An article of manufacture pattern for improving aerodynamic performance of a turbine including an abradable material capable of abradable contact. The abradable material is disposed in a pattern. The pattern includes a first plurality of ridges disposed at a base surface of the turbine. Each ridge of the first plurality of ridges has a first sidewall and a second sidewall having a first end and a second end. The first ends of the first and second sidewalls extend from the base surface. The first and second sidewalls slope toward each other with substantially equal but opposite slopes until meeting at the second ends of respective first and second sidewalls defining a centerline and a top portion of the ridge.

Abstract: A pattern for improving aerodynamic performance of a turbine includes a material disposed in a pattern at a base surface of a turbine shroud such that the material is capable of abradable contact with a tip portion of a turbine bucket. The pattern includes a first plurality of ridges disposed at the base surface such that a first portion of the first plurality of ridges corresponding to a back portion of the turbine bucket is oriented at a first angle with respect to an axis of rotation of the turbine bucket. Each ridge of the first plurality of ridges has a first sidewall and a second sidewall having a first end and a second end. The first ends of the first and second sidewalls extend from the base surface. The first and second sidewalls slope toward each other with substantially equal but opposite slopes until meeting at the second ends of respective first and second sidewalls defining a centerline and a top portion of the ridge.

Abstract: A seal having a first seal mechanism adapted for insertion between a first structure and a second structure, wherein the first structure is in communication with a first medium and the second structure is in communication with a second medium. The seal also includes a second seal mechanism, which is pressuringly biasable against the first seal mechanism and against the second structure by the second medium. In certain embodiments, a system has a first structure in communication with a first medium and a second structure houses a seal assembly between the first and second structures. The seal assembly includes an interface seal disposed against the first structure and a flexible seal pressuringly biased against the second structure and the interface seal by a second medium.

Abstract: A compliant seal for use between rotating blades and a static shroud surrounding the rotating blades in a steam or gas turbine is disclosed. The seal includes a tip surface, substantially resistant to wear due to rubbing by the tip of the rotating blades, and an elastic biasing member, comprising a biasing element. The wear-resistant surface is thus biased against the tips of the rotating blades to seal a gas path between the rotating blades and the static shroud.

Abstract: Method of producing a profiled abradable coating on a substrate in which an abradable ceramic coating composition is applied to a substrate using direct-write technology, or plasma sprayed onto the substrate through a mask or by use of a narrow foot-print plasma gun. These methods of producing abradable coatings are performed in the absence of a grid.

Abstract: A method of applying a profiled abradable coating onto a substrate in which an abradable ceramic coating composition is applied to a metal substrate using one or more coating application techniques to produce a defined ceramic pattern without requiring a separate web or grid to be brazed onto the substrate. The invention is particularly designed to withstand the higher operating temperatures encountered with the stage 1 section of 7FA+e gas turbines to allow for increased coating life without significant deterioration in structural or functional integrity. Typically, the grid pattern coating begins approximately 0.431? after the leading edge of the shroud, and ends approximately 1.60? before the trailing edge of the shroud. In the case of diamond-shaped patterns, the grid pattern will be about 0.28? long and 0.28? wide, with an overall thickness of about 0.46.