Abstract: A gas turbine engine having a turbine blade tip clearance control system for increasing the efficiency of the engine by reducing the gap between turbine blade tips and radially outward ring segments is disclosed. The turbine blade tip clearance control system may include one or more clearance control bands positioned radially outward of inner surfaces of ring segments and bearing against at least one outer surface of the ring segments to limit radial movement of the ring segments. During operation, the clearance control band limits radial movement of the ring segments, and the turbine blade tips do not have a pinch point during start-up transient conditions. In addition, the smallest gap during turbine engine operation may be found at steady state operation of the gas turbine engine. Thus, the clearance control system can set the gap between turbine blade tips and ring segments to be zero at steady state operation.

Abstract: A high-efficiency compressor section (10) for a gas turbine engine is disclosed. The compressor section includes a vane carrier (12) adapted to hold ring segment assemblies (16) that provide optimized blade tip gaps (28,29) during a variety of operating conditions. The ring segment assemblies include backing elements (30) and tip-facing elements (32) urged into a preferred orientation by biasing elements (40) that maintain contact along engagement surfaces (44,46). The backing and tip-facing elements have thermal properties sufficiently different to allow relative growth that strategically forms an interface gap (42) therebetween, resulting in blade tip gaps that are dynamically adjusted operation.

Abstract: A high-efficiency compressor section (10) for a gas turbine engine is disclosed. The compressor section includes a vane carrier (12) adapted to hold ring segment assemblies (16) that provide optimized blade tip gaps (28,29) during a variety of operating conditions. The ring segment assemblies include backing elements (30) and tip-facing, elements (32) urged into a preferred orientation by biasing elements (40) that maintain contact along engagement surfaces (44,46). The backing and tip-facing, elements have thermal properties sufficiently different to allow relative growth and geometric properties strategically selected to strategically form an interface gap therebetween (42) resulting in blade tip gaps that are dynamically adjusted operation.

Abstract: A gas turbine engine (10) having a turbine blade tip clearance control system (12) for increasing the efficiency of the engine (10) by reducing the gap (14) between turbine blade tips (16) and radially outward ring segments (18) is disclosed. The turbine blade tip clearance control system (12) may include one or more clearance control bands (20) positioned radially outward of inner surfaces (22) of ring segments (18) and bearing against at least one outer surface (24) of the ring segments (18) to limit radial movement of the ring segments (18). During operation, the clearance control band (20) limits radial movement of the ring segments (18), and the turbine blade tips (16) do not have a pinch point during start-up transient conditions. In addition, the smallest gap (14) during turbine engine operation may be found at steady state operation of the gas turbine engine (10).

Abstract: A high-efficiency compressor section (10) for a gas turbine engine is disclosed. The compressor section includes a vane carrier (12) adapted to hold ring segment assemblies (16) that provide optimized blade tip gaps (28,29) during a variety of operating conditions. The ring segment assemblies include backing elements (30) and tip-facing elements (32) urged into a preferred orientation by biasing elements (40) that maintain contact along engagement surfaces (44,46). The backing and tip-facing elements have thermal properties sufficiently different to allow relative growth and geometric properties strategically selected to strategically form an interface gap therebetween (42,43), resulting in blade tip gaps that are dynamically adjusted operation.

Abstract: A high-efficiency compressor section (10) for a gas turbine engine is disclosed. The compressor section includes a vane carrier (12) adapted to hold ring segment assemblies (16) that provide optimized blade tip gaps (28,29) during a variety of operating conditions. The ring segment assemblies include backing elements (30) and tip-facing elements (32) urged into a preferred orientation by biasing elements (40) that maintain contact along engagement surfaces (44,46). The backing and tip-facing elements have thermal properties sufficiently different to allow relative growth that strategically forms an interface gap (42,43) therebetween, resulting in blade tip gaps that are dynamically adjusted operation.

Abstract: A turbine engine heating system configured to heat compressor and turbine blade assemblies to eliminate turbine and compressor blade tip rub during warm restarts of gas turbine engines is disclosed. The turbine engine heating system may include a heating air extraction system configured to withdraw air from the turbine engine and to pass that air thru a heating element configured to increase a temperature of the air supplied by the heating air extraction system. The air may then be passed to a heating air supply system via an air movement device. The heating air supply system may be in communication with a turbine cylinder cavity of the turbine engine positioned radially outward from at least one turbine assembly. The heated air may be passed into the turbine cylinder cavity to reduce the cooling rate of the turbine vane carriers after shutdown and before a warm restart to limit tip rubbing.

Abstract: A measuring assembly for use in a gas turbine engine includes an indicia portion that extends radially inwardly from an inner surface of a ring seal structure to a location radially inwardly from tips of blades mounted on a rotor. The indicia portion of the measuring assembly comprises a section that is abraded by the blades during rotational movement of the rotor to provide a visual indication of a distance between the tips of the blades and the inner surface.

Abstract: A turbine airfoil support system for supporting a turbine blade to prevent wear during turning gear operation when a rotor assembly supporting the turbine blade rotates at about two revolutions per minute (RPM) to keep the turbine ready for quick startup requirements. The turbine airfoil support system may be formed from a radial biasing spring positioned between a radially outermost point of a disk steeple extending from a rotor assembly and a radially inner surface of the platform. The radial biasing spring may be formed from a first flat member with a disk steeple engaging surface, a second flat member with a blade platform engaging surface, a bent biasing section extending from the first flat member to the second flat member and biasing the first and second flat members away from each other, and a stress reducing member extending from the second flat member toward the first flat member.

Abstract: A measuring assembly for use in a gas turbine engine includes an indicia portion that extends radially inwardly from an inner surface of a ring seal structure to a location radially inwardly from tips of blades mounted on a rotor. The indicia portion of the measuring assembly comprises a section that is abraded by the blades during rotational movement of the rotor to provide a visual indication of a distance between the tips of the blades and the inner surface.

Abstract: A turbine airfoil support system for supporting a turbine blade to prevent wear during turning gear operation when a rotor assembly supporting the turbine blade rotates at about two revolutions per minute (RPM) to keep the turbine ready for quick startup requirements. The turbine airfoil support system may be formed from a radial biasing spring positioned between a radially outermost point of a disk steeple extending from a rotor assembly and a radially inner surface of the platform. The radial biasing spring may be formed from a first flat member with a disk steeple engaging surface, a second flat member with a blade platform engaging surface, a bent biasing section extending from the first flat member to the second flat member and biasing the first and second flat members away from each other, and a stress reducing member extending from the second flat member toward the first flat member.

Abstract: A turbine blade has a cooling air flow path specifically directed toward cooling the platform portion of the blade root. Two cooling air passages are formed in the blade root platform just below its upper surface. Each passage extends radially outward from an inlet that receives a flow of cooling air and then extend axially along almost the entire length of the platform. Each passage also has an outlet formed in the downstream face of the platform that allows the cooling air to exit the platform and enter the hot gas flow path. The passages are formed in portions of the platform that overhang the shank portion of root.

Abstract: A vane for the turbine section of a gas turbine has an airfoil portion with leading edge, center and trailing edge portions. The leading edge portion is attached to the center portion by a dove tail joint that allows the leading edge portion to slide in the radial direction with respect to the center portion while preventing movement in the axial and circumferential directions, thereby eliminating thermal stresses created by differential thermal expansion between the leading edge portion and the remainder of the vane. An opening in the vane inner shroud that is normally sealed by a closure plate allows the leading edge portion to be readily replaced in the event of damage. The leading edge portion may be formed from a ceramic material and need not be supplied with cooling air.