US 12,264,685 B1
Bleed valve assembly with valve shims for varying bleed flow in gas turbine engine compressors and method for operating
Kerry J. Lighty, Indianapolis, IN (US); Jonathan P. Acker, Indianapolis, IN (US); Douglas J. Kremer, Indianapolis, IN (US); Steven Mazur, Indianapolis, IN (US); and Mark E. Whitlock, Indianapolis, IN (US)
Assigned to Rolls-Royce North American Technologies Inc., Indianapolis, IN (US); and Rolls-Royce Corporation, Indianapolis, IN (US)
Filed by Rolls-Royce North American Technologies Inc., Indianapolis, IN (US); and Rolls-Royce Corporation, Indianapolis, IN (US)
Filed on Apr. 19, 2024, as Appl. No. 18/640,404.
Int. Cl. F04D 27/02 (2006.01)
CPC F04D 27/0215 (2013.01) 8 Claims
OG exemplary drawing
 
7. A bleed valve assembly for a gas turbine engine, the bleed valve assembly comprising
a manifold coupled to a case of a compressor of the gas turbine engine to control a flow of bleed air exiting the compressor, the manifold having an outer surface defining an air passageway formed in the manifold for the bleed air to exit the compressor through the manifold, wherein the air passageway defines a central axis of the bleed valve assembly,
a valve housing coupled with the manifold and configured to receive pressurized air, and
a piston received in the valve housing and configured to move selectively relative to the valve housing and the manifold in response to the valve housing receiving the pressurized air to close the air passageway of the manifold, wherein the piston is movable between an open position in which a bottom surface of the piston is spaced apart from the manifold to open the air passageway and a closed position in which the piston closes the air passageway,
wherein the bleed valve assembly is changeable, via addition or removal of one or more shims, between a reduced-flow configuration in which an upper surface of the piston engages the one or more shims located between the upper surface of the piston and an inner surface of the valve housing and the bottom surface of the piston is spaced a first axial distance from the outer surface of the manifold when the piston is in the open position so that the bleed air passes through the bleed valve assembly at a first predetermined rate, and a maximum-flow configuration in which the upper surface of the piston engages the inner surface of the valve housing and the bottom surface of the piston is spaced a second axial distance from the outer surface of the manifold so that the bleed air passes through the bleed valve assembly at a second predetermined rate, wherein the second axial distance is greater than the first axial distance and the second predetermined rate is greater than the first predetermined rate.