Abstract: An opposed flow high pressure-low pressure steam turbine balances thrust of the high pressure steam turbine with the thrust of the low pressure steam turbine allowing a reduction in size of thrust bearings. Higher stage reactions in both turbines may be incorporated since they are offset with the opposed flow, allowing a higher steam path efficiency. Opposed flow may be established through a cross-over pipe or utilizing a double high pressure shell.

Abstract: A steam-driven power plant includes a steam source providing steam at a desired pressure and a steam turbine operably connected to the steam source. The steam turbine includes a low pressure section and an intermediate pressure section. A low pressure admission conduit is configured to convey steam from the steam source to an entrance of the low pressure section and an intermediate pressure admission conduit is configured to convey steam from the steam source to a mid-steampath point of the intermediate pressure section. One or more valves are located between the steam source and the steam turbine to control a flow of steam from the steam source through the low pressure admission conduit and/or the intermediate pressure admission conduit.

Abstract: A steam turbine includes a casing including a steam inlet and an exhaust, the casing enclosing operative structure of the steam turbine; a valve controlling introduction of a steam flow at a location of the steam turbine to impact an enthalpic condition of steam exiting the exhaust; and a controller controlling operation of the valve to attain a desired enthalpic condition of steam exiting the exhaust. Controlling operation of the valve allows for attainment of a desired enthalpic condition of the steam exiting the exhaust for use in another industrial process without having to modify the steam turbine structure.

Abstract: A steam turbine includes a shaft operatively connecting a first turbine section and a second turbine section. A packing assembly is positioned about the shaft. A first conduit is fluidly connected to the packing assembly. The first conduit is configured to introduce a flow of low temperature, low pressure steam to the packing assembly. A second conduit is also fluidly connected to the packing assembly downstream from the first turbine section and upstream from the first conduit. The second conduit receives a portion of the high temperature, high pressure steam passing into the packing assembly from the first turbine section. A valve is fluidly connected to the second conduit. The valve is configured to be selectively operated so as to allow the high temperature, high pressure steam to mix with the low pressure, low temperature steam in the second conduit.

Abstract: A packing ring assembly for use between a rotating and a stationary component in a turbomachine is disclosed, the assembly including an arcuate packing ring casing, an arcuate packing ring segment positioned at least partially within the packing ring casing, and a resistance component configured to allow movement of the packing ring segment in an axial direction, relative to the rotating component, between a first and second position in response to a pressure condition. In one embodiment, the resistance component allows movement when the pressure condition comprises approximately 30% of the turbomachine load. Also disclosed is an altered surface topography of the rotating component to accommodate variable length teeth extending from the packing ring segment, such that when the packing ring segment is in the first position, a clearance between the packing ring segment and the rotating component is larger than when the packing ring segment is in the second position.

Abstract: A steam turbine flow adjustment system is disclosed. In one embodiment, the system includes a steam turbine having a first inlet port and a second inlet port for receiving inlet steam; a first conduit and a second conduit operably connected to a first valve and a second valve, respectively, the first conduit and the second conduit for providing the inlet steam to the first inlet port and the second inlet port, respectively; and a control system operably connected to the first valve and the second valve for controlling an amount of inlet steam flow admitted and pressure to each of the first inlet port and the second inlet port based upon a load demand on the steam turbine and an admission pressure of the inlet steam.

Abstract: A method of cooling a double flow steam turbine includes supplying steam flow to each nozzle of the sections of the turbine; reversing a portion of each steam flow to provide a reverse steam flow from an aft side to a forward side of each section. Each reverse steam flow is directed to an annular space between a rotor and a tub. The method further includes removing the reverse steam flows through a pipe, the pipe having a first end at the annular space at a first pressure and a second end at a second pressure that is lower than the first pressure. A double flow steam turbine, includes a pair of nozzles, each nozzle being provided at a section of the turbine; a rotor supporting buckets of the sections; a tub supporting the pair of nozzles; and a pipe extending from an annular space between the tub and the rotor. The pipe has a first end at the annular space and second end. A pressure at the first end of the pipe is greater than a pressure at the second end.

Abstract: The present application provides a variable steam seal system for use with a steam turbine. The variable steam seal system may include a seal steam header, a first pressure section, a first pressure seal positioned about the first pressure section, and a flow path through the first pressure seal and extending to the seal steam header. The first pressure seal may include a moveable seal packing ring for varying the flow path through the first pressure seal to the seal steam header.

Abstract: A double flow low-pressure (LP) steam turbine with an LP section that can be engaged and disengaged from a drive train is provided, as are methods for its use. In one embodiment, the invention provides a steam turbine comprising: a high pressure (HP) section; an intermediate pressure (IP) section adjacent the HP section; a first low pressure (LP) section; a second LP section; a crossover pipe connecting the IP section to the first LP section and the second LP section; a drive train extending through the HP section, the IP section, the first LP section, and the second LP section; a device for engaging and disengaging the second LP section from the drive train; a valve for alternately opening and closing a portion of the crossover pipe connecting the IP section to the second LP section; and at least one extraction port for extracting a quantity of steam from at least one of the following: the crossover pipe or an exhaust of the IP section.

Abstract: The present application provides a variable steam seal system for use with a steam turbine. The variable steam seal system may include a seal steam header, a first pressure section, a first pressure seal positioned about the first pressure section, and a flow path through the first pressure seal and extending to the seal steam header. The first pressure seal may include a moveable seal packing ring for varying the flow path through the first pressure seal to the seal steam header.

Abstract: A method and apparatus are disclosed for alleviating the problem of windage heating when flow, in a turbine running at full speed, no load, decreases greatly at the exhaust of the high pressure sections of the turbine. Valves connecting the different pressure levels of a heat recovery steam generator to the input of the turbine are adjusted to mix steam coming from the different pressure levels to create desired steam conditions at the inlet and the exhaust output of the turbine that allow the use of existing steam path hardware and thereby reduce the cost of such piping. In an alternative embodiment for a single pressure HRSG, high pressure saturated steam is extracted from the HSRG evaporator and then flashed into superheated steam when passing thru a control valve, that is then used to create the desired steam conditions at the inlet and the exhaust output of the turbine.

Abstract: A turbine system includes a valve coupled to a leak off line from a leak packing of a first turbine, the valve controlling a first steam flow used to maintain a constant self-sustaining sealing pressure to a second turbine across numerous loading conditions. A related method is also provided.

Abstract: A reverse flow tolerant brush seal arrangement for restricting the transfer of a pressurized fluid between a first and a second chamber along a moving shaft. Opposing backing plates are provided to stiffen brush bristle alignment on the moving shaft. Differential pressure between the chambers is aided by spring biasing to seat axial movement of a sliding brush seal against one of the opposing backing plates for stiffening to maintain a design clearance with a shaft being sealed.

Abstract: Solutions for clutching turbine wheels are disclosed. In one embodiment, an apparatus includes: a turbine rotor shaft; a plurality of turbine wheels affixed to the turbine rotor shaft; an independent turbine wheel engagably attached to the turbine rotor shaft; and a clutch operably connected to the turbine rotor shaft, the clutch configured to couple and decouple the independent turbine wheel from the turbine rotor shaft.

Abstract: A method and system for regulating the pressure of steam in a Steam Seal Header (SSH) for a pressurized machine is provided. In the SSH, the pressure of steam may be regulated according to the operating status of the pressurized machine. The variable pressure SSH system may maintain a pressure packing of the pressurized machine within an optimized pressure range.

Abstract: A method and system for increasing the efficiency of a turbomachine having an extraction system is provided. The extraction system may have multiple extraction ports from which the working fluid of the turbomachine is extracted to meet extraction load requirements of an independent process. The method and system may enable a control system to optimally determine the which extraction ports to draw the working fluid from for meeting the extraction load requirement. The optimal location may be determined by utilizing the data on the load requirement, where the extraction load requirement may be operationally distinct from the turbomachine load.

Abstract: A system for reducing flow separation in a turbo machine is provided, the system including a stationary vane coupled to a stationary vane support; at least one circumferential extraction band through the stationary vane or the stationary vane support; the circumferential extraction band having a first side proximate to an operative fluid flow through the turbo machine; at least one opening in the first side of the circumferential extraction band; and a channel having a first end in fluid connection with the circumferential extraction band and a second end extending through the stationary vane support, such that the operative fluid flow through the turbo machine is redirected through the extraction opening into the circumferential extraction band and through the channel towards a rotating blade.

Abstract: A system for a turbo machine is provided, including one or more channels that redirect steam that leaks through the root and/or the tip regions of a stage of the turbine to mix with the high efficiency main steam flow at the pitch region of the turbine where efficiency is the highest. This redirection of the steam results in a significant performance improvement that evens out the efficiency profile resulting in higher average efficiencies.

Abstract: Embodiments of the invention relate generally to turbines and, more particularly, to steam turbines, single-shaft combined-cycle turbines, and turbine systems having novel startup cooling flow configurations. In one embodiment, the invention provides a single-shaft combined-cycle turbine comprising: a gas turbine; a steam turbine including: a high-pressure section; an intermediate-pressure section; and a low-pressure section having a plurality of stages; a turbine shaft disposed within and between both the gas turbine and the steam turbine; a first cooling steam flow inlet adjacent a first of the plurality of stages of the low-pressure section; and a second cooling steam flow inlet adjacent a second of the plurality of stages of the low-pressure section.

Abstract: Embodiments of the invention relate generally to steam turbines, steam turbine systems, and methods for their operation and, more particularly, to high-pressure-intermediate-pressure (HPIP) steam turbine configurations having pressure drop-limited seals and exhibiting reduced mid-packing and/or end-packing leakage. One embodiment of the invention provides a combined high-pressure-intermediate-pressure (HPIP) steam turbine comprising: a high-pressure section; an intermediate-pressure section sharing a common rotor with the high-pressure section; at least one packing ring disposed along a length of the rotor and between the high-pressure section and the intermediate-pressure section; and at least one conduit having a first end disposed adjacent a packing ring and a second end disposed adjacent a steampath stage of the high-pressure section.