Systems and methods for reducing friction during gas turbine engine assembly may comprise, a rear hub which may comprise a conical web, a horizontal arm coupled to the conical web, and/or a hub kickstand coupled to the conical web. The conical web, horizontal arm, and/or hub kickstand may converge at a pivot point. The hub kickstand may be removably coupled to the tie shaft.

A compressor has a rotor. The rotor includes a plurality of impellers that include a disk having a solid structure having a buried center, and are adjacent to each other in an axial direction, and a plurality of bolts for fixing the plurality of impellers together. The disk has a disk surface facing the axial direction and a bolt hole penetrating the disk at a position deviated outward from an axis in a radial direction. The disk surface includes a contact surface of which at least a part is located outside the bolt hole in the radial direction, and a non-contact surface which is a region inside the contact surface in the radial direction.

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 0 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 fan includes: a shaft including an outer peripheral surface that includes a first circular-arc portion, and a first flat portion; and a boss portion including a fitting hole with an inner peripheral surface that includes a second circular-arc portion, and a second flat portion. The second circular-arc portion corresponds to the first circular-arc portion. The second flat portion corresponds to the first flat portion. One or both of the first flat portion and the second flat portion includes a notch in an end portion in a width direction of the one or both of the first flat portion and the second flat portion.

A fan includes: a shaft including an outer peripheral surface that includes a first circular-arc portion, and a first flat portion; and a boss portion including a fitting hole with an inner peripheral surface that includes a second circular-arc portion, and a second flat portion. The second circular-arc portion corresponds to the first circular-arc portion. The second flat portion corresponds to the first flat portion. One or both of the first flat portion and the second flat portion includes a notch in an end portion in a width direction of the one or both of the first flat portion and the second flat portion.

A fan module including variable-pitch blades, a fan rotor bearing the blades of the fan, each mounted to pivot about a pitch axis; a fan shaft extending along a longitudinal axis X inside the fan rotor and driving the fan rotor in rotation. A power shaft drives the fan shaft with a planetary gear speed reducer At least a first and a second bearing guide the rotation of the fan rotor, housed inside a lubrication chamber. A system varies the pitch of the fan blades, including a connecting mechanism connected to the blades of the fan and a controller acting on the connecting mechanism. The first bearing is disposed upstream of the speed reducer and the second bearing is disposed downstream of the speed reducer. The fan rotor is connected to the fan shaft by an annular trunnion extending at least along an upstream portion of the lubrication chamber.

A fan module including variable-pitch blades, a fan rotor bearing the blades of the fan, each mounted to pivot about a pitch axis; a fan shaft extending along a longitudinal axis X inside the fan rotor and driving the fan rotor in rotation. A power shaft drives the fan shaft with a planetary gear speed reducer At least a first and a second bearing guide the rotation of the fan rotor, housed inside a lubrication chamber. A system varies the pitch of the fan blades, including a connecting mechanism connected to the blades of the fan and a controller acting on the connecting mechanism. The first bearing is disposed upstream of the speed reducer and the second bearing is disposed downstream of the speed reducer. The fan rotor is connected to the fan shaft by an annular trunnion extending at least along an upstream portion of the lubrication chamber.

An integrated gas compressor is disclosed herein. The integrated gas compressor includes an integrated motor with a stator, centrifugal impellers, and a shaft assembly with a rotor and conical transition. The integrated motor can produce an electromotive force that is imparted by the stator to rotate the rotor and components coupled to the rotor, such as the conical transition and the centrifugal impellers. At least one of the rotor and conical transition have a cavity.

An integrated gas compressor is disclosed herein. The integrated gas compressor includes an integrated motor with a stator, centrifugal impellers, and a shaft assembly with a rotor and conical transition. The integrated motor can produce an electromotive force that is imparted by the stator to rotate the rotor and components coupled to the rotor, such as the conical transition and the centrifugal impellers. At least one of the rotor and conical transition have a cavity.

An electrical submersible well pump assembly has first and second permanent magnet motors. The first motor drive shaft is connected to a coupling that has internal splines for receiving an externally splined end of the second motor drive shaft. Alignment devices rotationally align magnetic poles of the first drive shaft with the magnetic poles of the second drive shaft prior to securing the housings of the first and second motors together. The alignment devices may be a coupling irregularity in the internal splines that is at a controlled orientation relative to the magnetic poles of the first shaft and a shaft irregularity in the external splines that prevents the second drive shaft from fully engaging the coupling unless the shaft irregularity is in a specified rotational position relative to the coupling irregularity.