Methods for performing in situ balancing of an internal rotating component of a gas turbine engine are provided. The method can include inserting a repair tool through an access port of the gas turbine engine with the repair tool including a tip end positioned within the gas turbine engine and a material supply end positioned outside the gas turbine engine. The tip end of the repair tool is positioned adjacent to a surface of the internal rotating component of the gas turbine engine. A new material is supplied from the material supply end of the repair tool to the tip end of the repair tool; and is expelling from the tip end of the repair tool in a direction of the surface of the rotating component such that the new material is added onto a portion of the rotating part.

A balance weight assembly for a rotor blade of a rotorcraft. The balance weight assembly includes a balance weight pocket formed by a balance weight tray and a cover. The balance weight tray has an upper surface including a lip region extending outwardly from a projected region with an outboard boss. A balance weight receiving cavity is recessed from the upper surface and contains a plurality of balance weights. The projected region is disposed within an opening in a hollow blade spar such that the outboard boss of the balance weight tray has a contact relationship with an outboard surface of the opening. The cover is coupled to the balance weight tray such that the lip region of the balance weight tray and at least a portion of the cover have a clamping relationship with the blade spar, thereby coupling the balance weight pocket to the blade spar.

A turbomachinery rotor apparatus includes: a rotatable disk having an array of slots spaced around its periphery; an array of blades installed in the slots, wherein the blades have variable weights; and a plurality of connection components installed in the disk, each connection component forming a portion of a mechanical joint between one of the blades and its respective slot, wherein the connection components have variable weights.

A method, including: replacing an original blade shelf (16) of a gas turbine engine blade (10) with a new blade shelf (64) that is located closer to a base (18) of the blade than the original blade shelf; adding mass to the blade until a mass of the blade with the new blade shelf is greater than a mass of the blade with the original blade shelf in order to maintain a same contribution by the blade with the new blade shelf as a contribution by the blade with the original blade shelf to a dynamic balance of a rotor arrangement.

A method of loading a rotating assembly of a turbocharger can include positioning a swage collar on an end portion of a turbocharger shaft that extends through a through bore of a compressor wheel; applying a pulling force to the end portion of the turbocharger shaft to achieve a desired amount of loading; deforming the swage collar to form a swaged collar fixed to the end portion of the turbocharger shaft; and releasing the pulling force wherein the swaged collar maintains the desired amount of loading.

A compressor wheel assembly of a turbocharger can include a compressor wheel that includes a through bore that extends from a base portion to a nose portion of the compressor wheel; a turbocharger shaft disposed in the through bore of the compressor wheel where the turbocharger shaft includes an end portion that extends axially away from the nose portion of the compressor wheel; and a swaged collar fixed to the end portion of the turbocharger shaft.

An epicyclic gear train includes a carrier that supports star gears that mesh with a sun gear. A ring gear surrounds and meshes with the star gears. The star gears are supported on respective journal bearings. Each of the journal bearings includes a peripheral journal surface and each of the star gears includes a radially inner journal surface that is in contact with the peripheral journal surface of the respective journal bearing.

A bladed rotor system for a turbomachine includes a circumferential row of blades mounted on a rotor disc, and includes a plurality of under-platform dampers. Each damper is located between adjacent blade platforms. The plurality of dampers includes a first set of dampers and a second set of dampers. The dampers of the first set are distinguished from the dampers of the second set by a cross-sectional material distribution in the damper that is unique to the respective set. Dampers of the first set and the second set are positioned alternately in a periodic fashion in a circumferential direction, to provide a frequency mistuning to stabilize flutter of the blades.

A method of bowed rotor start response damping for a gas turbine engine is provided. A spring rate and a damping characteristic of one or more bearing supports in the gas turbine engine are selectively modified while a shaft of the gas turbine engine rotates below a speed which is adversely affected by a bowed rotor condition of the gas turbine engine.

The invention concerns a turbomachine rotor (1), characterised in that it comprises a threaded or tapped part (3, 6) and a damping nut (8) screwed onto the threaded or tapped part (3, 6) so as to allow the threads of the nut (8) and of the threaded or tapped part (3, 6) to rub against each other in the event of vibration of the rotor (1).