A turbine section for a gas turbine engine according to an example of the present disclosure includes, among other things, a first turbine rotor coupled to a first turbine shaft. The first turbine shaft is rotatable about a longitudinal axis. A second turbine rotor is coupled to a second turbine shaft. The second turbine shaft is rotatable about the longitudinal axis, and the second turbine rotor is axially aft of the first turbine rotor relative to the longitudinal axis. An aft bearing assembly rotatably supports the second turbine shaft. The second turbine rotor includes a disk assembly that carries at least one row of turbine blades. The disk assembly is mechanically attached to the second turbine shaft at an attachment point. The attachment point is axially aft of the aft bearing assembly such that an aft portion of the second turbine shaft is cantilevered from the aft bearing system with respect to the longitudinal axis. The disk assembly includes a metallic material. Each of the turbine blades comprises a ceramic matrix composite (CMC) material.

A gas turbine engine rotor assembly, comprising: a shaft about an axis having an outer surface radially outward and a groove radially into the outer surface; a disc surrounding the shaft rotatable with the shaft about the axis, the disc having an inner surface extending axially defining an inner diameter, having a disc profile around the groove and axially away from and radially inwardly of the inner diameter, the shaft and the disc defining a gap circumscribed outwardly by the inner diameter and inwardly by the outer surface; and a seal including a split ring fitted into the groove and rotatable with the shaft about the axis, the ring having a ring profile complementary to the disc profile, the ring resiliently expandable radially in the gap to the inner diameter, the disc profile cooperable with the ring profile to axially load the shaft via the ring expanded across the gap.

Tooling for producing scallops and fastening holes of a clamp of a disc by electrochemical machining using an electrolyte, the tooling having: an annular support tray to receive the disc; lower and upper shields configured to protect the disc from splashes of the electrolyte; a clamping lock to hold the disc in position during machining; and a die-sinking tool having in a substantially cylindrical insulating body a first and a second coaxial conductive cathode, the first and second cathodes rigidly fastened to each other, the first annular cathode including at an external periphery a plurality of radial machining protrusions of a shape complementary to that of the scallops to be machined and the second cathode includes, on the same circumference external to the first cathode relative to the central axis of the disc, a plurality of axial machining nozzles of a shape similar to the fastening holes to be machined.

This invention relates to a multi-stage rotor (10). More specifically, the invention relates to a multistage rotor (10) for the compressor stage of a machine that, through a concentric configuration of its innermost (12), outermost (24) and intermediary (16) blade sets co-operative with a reverse flow convoluting ducting arrangement, provides an axially compact, lighter and more easily maintainable compressor rotor for such machine. The multi-stage rotor (10) includes innermost (30), outermost (34) and intermediary (32) duct ports comprising a radial duct spans, as measured between respective diametrically inner and outer duct walls of the duct port, being greater than respective innermost (48), outermost (54) and intermediary (50, 52) radial blade spans of the respective blade sets rotatable at least partially within such duct port. In this manner, a gap is defined between: (i) the at least one diametrical ends of the radial rotating blades ending radially short of the respective radial duct span to form free ends of the blades; and (ii) a stationary part of the respective duct the free ends of the blades sweep neared to; for generating a friction wash between such free ends of the blades and the stationary part of the respective duct.

A turbomachine includes a housing and a rotating group that is supported for rotation about an axis within the housing. The rotating group includes a rotor shaft, a wheel, and a fastener that clamps the wheel to the rotor shaft. The fastener is unitary and includes a head and a shank. The shank includes a piloting feature on an arcuate surface that faces radially outward with respect to the axis. The shank is received in the wheel and is attached to the rotor shaft with the piloting feature being piloted to an arcuate inner radial surface of the wheel. The head abuts an axial surface of the wheel for axially clamping the wheel to the rotor shaft.

A rotor assembly comprises a rotor having annular flange including a plurality of protrusions axisymmetrically disposed about the annular flange, each protrusion having a mounting aperture for selectively receiving a balancing feature, and a plurality of slots axisymmetrically disposed about the circumference of the annular flange between adjacent protrusions. Each slot has a pair of converging flat portions extending axially inwardly from an adjacent protrusion end, an inner flat portion at an inner end of each slot, and a pair of curved portions respectively joining each converging flat portion to the inner flat portion in each slot. Each slot has a depth at least as great as an adjacent mounting aperture depth extending normally from the adjacent protrusion end to a far end of the corresponding mounting aperture.

A retention assembly for interconnecting first and second rotating components in a gas turbine engine. The second component includes an engagement portion defining protrusions circumferentially spaced apart and extending axially therefrom. A threaded fastener axially retains the second rotating component to the first and has key-receiving slots and a circumferentially-extending groove. A key washer is mounted to the fastener and defines first and second axial surfaces. The key washer has a first set of keys extending radially inwardly from a radially inner surface and received within the key-receiving slots and a second set of keys extending from the second axial surface. A retaining ring is disposed within the groove, is radially retained by the protrusions extending axially from the second component, axially retained between the second set of keys and the second axial surface, and radially spaced apart from the second set of keys to define a radial gap therebetween.

A rotor assembly adapted for a gas turbine engine includes a shaft, a wheel, and a retaining nut. The shaft extends along an axis and includes a first tapered surface. The wheel is arranged circumferentially around the shaft and includes a second tapered surface. The retaining nut is fastened to the shaft and applies an axial force to the wheel to couple the wheel with the shaft.

The rotor assembly can have a first disc having a first body extending circumferentially and radially around the axis, a first set of circumferentially distributed blades protruding radially from the first disc, and a male spline extending axially relative the first body, the male spline extending around and along the axis, and a second disc having a second body extending circumferentially and radially around the axis, a second set of circumferentially distributed blades protruding radially from the second disc, and a female spline extending around and along the axis, the female spline receiving the male spline in a spline engagement.

A gas turbine engine rotor assembly, comprising: a shaft about an axis having an outer surface radially outward and a groove radially into the outer surface; a disc surrounding the shaft rotatable with the shaft about the axis, the disc having an inner surface extending axially defining an inner diameter, having a disc profile around the groove and axially away from and radially inwardly of the inner diameter, the shaft and the disc defining a gap circumscribed outwardly by the inner diameter and inwardly by the outer surface; and a seal including a split ring fitted into the groove and rotatable with the shaft about the axis, the ring having a ring profile complementary to the disc profile, the ring resiliently expandable radially in the gap to the inner diameter, the disc profile cooperable with the ring profile to axially load the shaft via the ring expanded across the gap.