A rotor assembly for a gas turbine engine includes a turbine shaft disposed about a longitudinal axis, a first rotor and a second rotor configured for rotation about the longitudinal axis, and an intermediate shaft positioned radially between the turbine shaft and the second rotor. The second rotor is mounted to and axially adjacent the first rotor. The intermediate shaft is mounted to the turbine shaft on an inner radial side of the intermediate shaft. The intermediate shaft is mounted to the second rotor on an outer radial side of the intermediate shaft.

A fastener cover for a flanged joint including first and second annular flanges extending about an axis, comprising: an annular, axially-extending, inboard wall; an annular, axially-extending outboard wall positioned radially outboard of the inboard wall; and a first radial wall interconnecting the inboard and outboard walls, wherein, collectively, the inboard and outboard walls and the first radial wall define a cavity for receiving a portion of a fastener; at least one fastener pocket including sidewalls extending axially away from the first radial wall and defining a tubular shape, which is closed off opposite the first radial wall by a floor plate having a clearance hole passing therethrough for accepting a shank of the fastener; and wherein the cover includes a balance weight receptacle for accepting at least one balance weight.

An air starter for an engine, such as a turbine engine, that includes a turbine for rotatably extracting mechanical power from a flow of fluid. The turbine includes a drive shaft that can be coupled to an output shaft to provide a rotational output. The interface between the drive shaft and the output shaft can be offset.

An impeller attach mechanism for a turbocharger including a stud extending from a central bore of a compressor impeller toward a turbine wheel, the stud having a first threaded region and a second threaded region; a shaft coupled to the turbine wheel and extending toward the compressor impeller, the shaft having a leading portion, the leading portion having a threaded interior configured to engage the second threaded region of the stud; and an insert having an internal portion and an external portion, the internal portion having a threaded external surface to engage the compressor impeller, the internal portion having a threaded internal surface to engage the first threaded region of the stud, the external portion configured to surround the leading portion of the shaft.

An impeller attach mechanism for a turbocharger including a stud extending from a central bore of a compressor impeller toward a turbine wheel, the stud having a first threaded region and a second threaded region; a shaft coupled to the turbine wheel and extending toward the compressor impeller, the shaft having a leading portion, the leading portion having a threaded interior configured to engage the second threaded region of the stud; and an insert having an internal portion and an external portion, the internal portion having a threaded external surface to engage the compressor impeller, the internal portion having a threaded internal surface to engage the first threaded region of the stud, the external portion configured to surround the leading portion of the shaft.

A rotary machine includes a cylindrical rotary shaft extending in a direction of an axis, a fastening bolt having a bolt body that extends in a direction of an axis O in the rotary shaft to form fastening portions at both ends, a pair of rotary bodies each having an end portion in the direction of the axis that is fixed to each of the pair of fastening portions to be in contact with an end surface of the rotary shaft in the direction of the axis, and a bolt extension mechanism that temporarily extends the bolt body in the direction of the axis.

A process for treating a centrifugal compressor wheel includes a combination of cold expansion of at least part of the bore of the wheel to induce residual compressive stresses in a region around the bore, and surface peening at least parts of the compressor wheel such as the back disk and portions of the blades.

An exhaust-gas turbocharger (1) with a compressor wheel (2); with a turbine wheel (3); and with a shaft (4) on which the compressor wheel (2) and the turbine wheel (3) are arranged in a rotationally secured manner. The turbine wheel (3) has a through-opening (5) in which a first end region (6) of the shaft (4) is arranged, and the turbine wheel (3) is braced between an end-side stop (7) connected to the end region (6) and a compressor wheel-side shaft sleeve (8) fixed on the shaft (4).

An apparatus and method of reducing a flow of fluid and heat between a first space and a second space in a rotatable machine and an integral seal and heat shield device are provided. The device includes an annular flange configured to couple to the rotating member of the rotatable machine and a multi-walled seal shield member extending axially from the flange. The multi-walled seal shield member is formed integrally with the flange. The seal shield member includes a first wall including a plurality of surface features, a second wall spaced radially inwardly with respect to the first wall, and a cavity formed between the first and second walls. The integral seal and heat shield device also includes a cap end integrally formed and configured to seal the first and second walls. Each of the flange, the seal shield member, and the cap end are formed of a sintered metal.

A fan disc is provided for supporting fan blades of a gas turbine engine. The fan disc has a disc body having axially extending slots for receiving, in use, dovetail root fixings of a circumferential row of fan blades. The fan disc further has an annular drive arm which extends radially inwardly from a forward portion of the disc body to a connector for engaging, in use, with a corresponding connector portion of a drive shaft of the engine. The fan disc further has a hoop stiffening ring which is removably mounted to a rear portion of the disc body, the stiffening ring being axially spaced from the drive arm to increase the torsional stiffness of the fan disc.