Patent ID: 6832890
Filing Date: 2004-12-21
Classification: F01D,F04D,F05D,Y02T

Abstract:
An arrangement for a gas turbine engine, the arrangement comprising a rotor and a surrounding casing, said casing having a generally cylindrical inner surface, said inner surface having a first cylindrical section and a second, axially adjacent cylindrical section, said first section being provided with a plurality of recesses in a circumferential arrangement and said second section being provided with an abradable lining, said rotor comprising an annular array of rotor blades, each blade having an outer tip, and each of said tips comprising a treated portion and an untreated portion wherein said treated portion of said tip is at least partly located opposite said first cylindrical section of the inner surface of said casing and said untreated portion of said tip is at least partly located opposite said second cylindrical section of the inner surface of said casing.