Abstract: A steam turbine includes a high pressure stage, a low pressure stage, and a controller operatively connected to at least the low pressure stage. The low pressure stage includes a first low pressure section having a sensor configured for detecting operation data of the first low pressure section, and at least one second low pressure section. The controller is programmed or configured to receive the operation data from the first sensor during operation of the first low pressure section and determine at least one performance characteristic of the first low pressure section based on the operation data. The controller is further programmed or configured to turn off the first low pressure section when the at least one performance characteristic of the first low pressure section is outside a predetermined performance threshold, and turn on the second low pressure section. A method of operating the steam turbine is also disclosed.

Abstract: A bearing includes a thrust gas bearing attached to a journal bearing and two or more converging-diverging orifices defined in a surface of at least one of the thrust gas bearing and the journal bearing. The converging-diverging orifices supply at least one pressurized gas to an interior of the bearing. Hydrodynamic lifting grooves are provided on the faces of the thrust gas bearing and the journal bearing and provide improved load capacity and sealing capabilities. Control over the ratios of the pressurized gases provides for additional sealing capabilities and reduced leakage. A metal mesh damper provides increased damping of the gas bearing.

Abstract: An arrangement for intentionally mistuning a cavity formed adjacent an impeller in a turbomachine, the arrangement including at least two bladed elements defined within a perimeter of a casing wall adjacent the impeller, wherein the bladed elements are configured to mistune cavity acoustic modes to minimize acoustic pulsations in the cavity.

Abstract: A turbomachine includes a casing having an inlet end opposite an outlet end along a longitudinal axis of the casing; a shaft assembly provided within the casing, the shaft assembly extending from the inlet end to the outlet end; a plurality of rotating impellers extending radially outward from the shaft assembly; and a communication channel defined between two adjacent impellers to permit a backflow of fluid from a diffuser channel of a downstream impeller to a return channel of an adjacent upstream impeller.

Abstract: A turbomachine including a housing having an inlet end opposite and outlet end along a longitudinal axis of the housing, a shaft assembly provided within the housing, the shaft assembly extending from the inlet end to the outlet end, a rotor having at least one rotating impeller extending radially outward from the shaft assembly, and a return channel vane hub extending radially outward from the shaft assembly, the return channel vane hub includes at least one return channel vane extend therefrom, the at least one return channel vane comprising a body having a leading edge and a trailing edge, the leading edge is twisted and extended past an outer edge of the return channel vane hub, and the trailing edge is bowed outwardly.

Abstract: A pneumatic trip system for a turbine includes a valve member; a valve stem connected to the valve member; and an actuator assembly connected to the valve stem. The actuator assembly includes a cylinder; a piston connected to the valve stem, the piston dividing the cylinder into a first chamber and a second chamber; a biasing element disposed in the second chamber of the cylinder; and a pneumatic circuit in communication with the second chamber of the cylinder. The pneumatic circuit is configured to pressurize the second chamber of the cylinder to actuate the piston to move the valve stem and the valve member to an exercised position between the open position and the closed position while the first chamber is pressurized.

Abstract: A fluid bearing for use in turbomachinery including at least one bearing pad configured to be arranged about a rotating member of the turbomachinery. Each bearing pad includes an internal cooling opening defined in the bearing pad and an internal channel network defined in the bearing pad with at least one channel node in fluid communication with the internal cooling opening and at least two passageways in fluid communication with and extending from the channel node through the bearing pad. At least one of the passageways extends to an exterior surface of the bearing pad to define at least one cooling discharge opening.

Abstract: A gas turbine device includes an inlet casing and a stator diaphragm provided inside the inlet casing. The stator diaphragm has an integral inner stator shroud and an outer stator shroud and a plurality of stator vanes provided in a circumferential arrangement between the inner stator shroud and the outer stator shroud. A plurality of key slots is provided in a circumferential arrangement on the stator diaphragm and a corresponding plurality of key slots is provided in a circumferential arrangement on the inlet casing. The key slots provided on the stator diaphragm are aligned with the plurality of key slots provided on the inlet casing. A key is inserted into each of the plurality of key slots provided to prevent rotation of the stator diaphragm with respect to the inlet casing. The stator diaphragm is secured in an axial direction by a stator shear ring.

Abstract: A thrust bearing includes a bearing retainer including a first ring and a second ring radially spaced from the first ring, the first ring and the second ring defining an annular passageway therebetween, and at least two bearing pad retaining arrangements extending from a first surface of the second ring, each bearing pad retaining arrangement defining a retaining channel therein, and at least two bearing pads circumferentially spaced within the bearing retainer. The bearing pads may be held within the bearing retainer via the bearing pad arrangements.

Abstract: A turbomachine includes a plurality of rotating blades adjacent to a plurality of stationary vanes attached to a stationary casing. Stationary vanes are spaced apart circumferentially with equal spacing around an inner perimeter of the casing. Optionally, stationary vanes are offset radially and/or circumferentially. Stationary vanes may alternate with leading and/or trailing edges at different distances from the rotating blades. In one embodiment, stationary vanes have tapered leading and/or trailing edge angles to homogenize flow and reduce stator wake excitation, flow excitation, and acoustic excitation due to interaction with spinning modes of acoustic pressure pulsations at rotating blade passing frequency.

Abstract: A brush ring seal device for installation within a packing case of a turbine includes: a brush seal carrier having a substantially ring-shaped body portion having a front face, a rear face, an inner circumferential groove, and an outer circumferential groove; a brush seal mounted within the inner circumferential groove of the brush seal carrier; and a ring-shaped spring mounted within the outer circumferential groove of the brush seal carrier. The rear face of the brush seal carrier is coated with an anti-friction coating, thereby allowing movement of the brush ring seal device within the packing case.

Abstract: A method for casting a diafram having inner and outer rings with preformed vanes circumferentially spaced therebetween is disclosed. A digital representation of a sand core is created. Based on this digital representation, a sand core is produced by bonding together successive layers of sand with droplets of a binder material using a binder printhead having nozzles for supplying jets of binder material droplets. A plurality of vanes is inserted into the cavities of the sand core. The sand core is then placed into a casting mold and filled with liquid metal. After the liquid metal has solidified and cooled, the sand core and any remaining sand is removed from the cast diafram.

Abstract: An apparatus for exercising an emergency shutoff valve of a steam turbine and methods for operating the same are disclosed herein. A cover of the valve exerciser mounts on top of an emergency shutoff valve body and through a stroker bolt threadingly engaged with the shutoff valve lever arm, the valve stem is moved within a passageway of the cover a small amount so that the aperture between the steam inlet and outlet is not blocked, thereby permitting normal operation of the steam valve while the valve stem is exercised.

Abstract: A turbomachine includes a plurality of rotating blades adjacent to a plurality of stationary vanes attached to a stationary casing. Stationary vanes are spaced apart circumferentially with equal spacing around an inner perimeter of the casing. Optionally, stationary vanes are offset radially and/or circumferentially. Stationary vanes may alternate with leading and/or trailing edges at different distances from the rotating blades. In one embodiment, stationary vanes have tapered leading and/or trailing edge angles to homogenize flow and reduce stator wake excitation, flow excitation, and acoustic excitation due to interaction with spinning modes of acoustic pressure pulsations at rotating blade passing frequency.

Abstract: A method of positioning a bearing of a turbomachine in a squeeze film annulus is disclosed. The method includes providing a bearing in which a rotor shaft is disposed and a bearing support mounted about and radially supporting the bearing, with the bearing support at least in part defining the squeeze film annulus. A further step typically includes providing a plurality of centering elements associated with the bearing and bearing support and acting to center the bearing within the squeeze film annulus, with the centering elements provided at radially spaced locations around the bearing. An additional step in the method may include individually machining or shimming the centering elements to adjust the positioning of the bearing in the squeeze film annulus or to impart pre-load to improve the resiliency of the centering elements.

Abstract: A method for casting a diafram having inner and outer rings with preformed vanes circumferentially spaced therebetween is disclosed. A digital representation of a sand core is created. Based on this digital representation, a sand core is produced by bonding together successive layers of sand with droplets of a binder material using a binder printhead having nozzles for supplying jets of binder material droplets. A plurality of vanes is inserted into the cavities of the sand core. The sand core is then placed into a casting mold and filled with liquid metal. After the liquid metal has solidified and cooled, the sand core and any remaining sand is removed from the cast diafram.

Abstract: An assembly and method for an axial compressor includes an axial shaft extending between an inlet casing and a discharge casing along the longitudinal length of a compressor housing. The axial shaft assembly includes a first stub shaft, a second stub shaft, and a hollow shaft drum having a longitudinal axis. The first stub shaft and the second stub shaft are coupled to opposing ends of the shaft drum along its longitudinal axis. A plurality of keys is disposed in a radial arrangement near the outer circumference of the first and second stub shafts and the shaft drum. A plurality of pins engage the plurality of keys, whereby the pins prevent the shaft drum from rotating axially relative to the first stub shaft and the second stub shaft and prevent the shaft drum from axially and radially separating from the stub shafts.

Abstract: A passive dynamic inertial rotor balance system including a plurality of balancing members fitted onto a rotor shaft at locations of predicted maximum shaft modal deflection. Each of the balancing members has at least one chamber and located within the at least one chamber is a plurality of movable weights and a viscous fluid. As the shaft accelerates toward an unbalance point, the weights move within the at least one chamber to a location which is opposite from the unbalance point. The viscous fluid provides damping for the movable weights to prevent excess movement within the chamber and to provide lubrication thereof. A system for self-correcting an unbalance of a turbomachinery rotor during rotation of the rotor and a method for balancing a rotor in a turbomachinery is also provided.

Abstract: A brush ring seal device for installation within a packing case of a turbine includes: a brush seal carrier having a substantially ring-shaped body portion having a front face, a rear face, an inner circumferential groove, and an outer circumferential groove; a brush seal mounted within the inner circumferential groove of the brush seal carrier; and a ring-shaped spring mounted within the outer circumferential groove of the brush seal carrier. The rear face of the brush seal carrier is coated with an anti-friction coating, thereby allowing movement of the brush ring seal device within the packing case.