Patent Application
20140154065
The subject matter disclosed herein relates to power systems. More particularly, the subject matter relates to turbomachine systems.
Conventional turbomachines (also referred to as turbines), such as steam turbines (or, steam turbomachines), generally include static nozzle assemblies that direct the flow of working fluid (e.g., steam) into rotating buckets that are connected to a rotor. In steam turbines the nozzle (or, airfoil) construction is typically called a “diaphragm” or “nozzle assembly” stage. Nozzle assemblies are assembled in two halves around the rotor, creating a horizontal joint.
In a double-flow (or dual-flow) steam turbine, inlet steam is directed through an inlet passageway and divided (split) into two axial passageways connecting with a first and second side of the turbine. Conventionally, the flow is divided using a structure called a flow splitter. After the steam flow is divided, the steam flows axially in opposite directions through the nozzle/bucket stages of each side of the turbine.
Some conventional flow splitter designs include large, heavy and costly structures which include two mirror image-like axial halves that are bolted together through large flanges. The bolt is traditionally aligned on an inside radial surface of the axial halves, between the flow splitter and the rotor body. Each half of the flow splitter is conventionally machined from a large forging, which results in a significant amount of stock material being wasted during the forging process. In other conventional flow splitter designs, a unitary splitter structure is formed and then machined to include hooks for engaging complementary hooks on the diaphragm and maintaining a radial and axial position of the flow splitter. However, the process of forming this unitary structure, e.g., via forging and subsequent machining, can be complicated and time consuming. Additionally, the hooks of these conventional flow splitters also react with a portion of the axial pressure force on the nozzle stage, which can cause maintenance related issues after the turbine has operated for an extended period.
Various embodiments include a turbomachine flow divider. In various particular embodiments, a flow divider for connecting with a first inner diaphragm ring and a second inner diaphragm ring of a turbomachine is disclosed. The flow divider includes: a body section; and a pair of axially extending flanges extending from the body section, each of the axially extending flanges for engaging with the first inner diaphragm ring and the second inner diaphragm ring, respectively, wherein the flow divider is formed substantially of a rolled plate metal or a sheet metal.
A first aspect of the invention includes a flow divider for connecting with a first inner diaphragm ring and a second inner diaphragm ring of a turbomachine. The flow divider includes: a body section; and a pair of axially extending flanges extending from the body section, each of the axially extending flanges for engaging with the first inner diaphragm ring and the second inner diaphragm ring, respectively, wherein the flow divider is formed substantially of a rolled plate metal or a sheet metal.
A second aspect of the invention includes a turbomachine diaphragm section having: a first diaphragm stage in a first turbomachine section, the first diaphragm stage having a first inner diaphragm ring and a first outer diaphragm ring; a second diaphragm stage in a second turbomachine section opposing the first turbomachine section, the second diaphragm stage having a second inner diaphragm ring and a second outer diaphragm ring; a flow divider connected with the first inner diaphragm ring and the second inner diaphragm ring for dividing flow of a working fluid into each of the first diaphragm stage and the second diaphragm stage, the flow divider including: a body section having a substantially planar radially outer surface; and a pair of axially extending flanges extending from the body section, each flange engaging with the first inner diaphragm ring and the second inner diaphragm ring, respectively; and a set of key members proximate a horizontal joint of the flow divider between at least one of the pair of axially extending flanges and at least one of the first inner diaphragm ring or the second inner diaphragm ring.
A third aspect of the invention includes a dual-flow turbomachine including: a first section having a first diaphragm stage with a first inner diaphragm ring and a first outer diaphragm ring; a second section opposing the first section, the second section having a second diaphragm stage with a second inner diaphragm ring and a second outer diaphragm ring; a flow divider connected with the first inner diaphragm ring and the second inner diaphragm ring for dividing flow of a working fluid into each of the first diaphragm stage and the second diaphragm stage, the flow divider including: a body section having a substantially planar radially outer surface; and a pair of axially extending flanges extending from the body section, each flange engaging with the first inner diaphragm ring and the second inner diaphragm ring, respectively; and a set of key members proximate a horizontal joint of the flow divider between at least one of the pair of axially extending flanges and at least one of the first inner diaphragm ring or the second inner diaphragm ring.
These and other features of this invention will be more readily understood from the following detailed description of the various aspects of the invention taken in conjunction with the accompanying drawings that depict various embodiments of the invention, in which:
It is noted that the drawings of the invention are not necessarily to scale. The drawings are intended to depict only typical aspects of the invention, and therefore should not be considered as limiting the scope of the invention. In the drawings, like numbering represents like elements between the drawings.
As noted, the subject matter disclosed herein relates to power systems. More particularly, the subject matter relates to turbomachine systems.
As described herein, some conventional flow splitter designs include large, heavy and costly structures which include two mirror image-like axial halves that are bolted together through large flanges. The bolt is traditionally aligned on an inside radial surface of the axial halves, between the flow splitter and the rotor body. Each half of the flow splitter is conventionally machined from a large forging, which results in a significant amount of stock material being wasted during the forging process. In other conventional flow splitter designs, a unitary splitter structure is formed and then machined to include hooks for engaging complementary hooks on the diaphragm and maintaining a radial position of the flow splitter. However, the process of forming this unitary structure, e.g., via forging and subsequent machining, can be complicated and time consuming. Another issue with the conventional flow splitter design is that the hooks can cause difficulty in assembling the flow splitter and adjacent diaphragm stages, and these flow splitters are difficult to disassemble after a period of operation, e.g., once corrosion and oxidation has occurred.
Various embodiments include a turbomachine flow divider. In various particular embodiments, a flow divider for connecting with a first inner diaphragm ring and a second inner diaphragm ring of a turbomachine is disclosed. The flow divider includes: a body section; and a pair of axially extending flanges extending from the body section, each of the axially extending flanges for engaging with the first inner diaphragm ring and the second inner diaphragm ring, respectively, wherein the flow divider is formed substantially of a rolled plate metal or a sheet metal.
Various particular embodiments of the invention include a turbomachine diaphragm section having: a first diaphragm stage in a first turbomachine section, the first diaphragm stage having a first inner diaphragm ring and a first outer diaphragm ring; a second diaphragm stage in a second turbomachine section opposing the first turbomachine section, the second diaphragm stage having a second inner diaphragm ring and a second outer diaphragm ring; a flow divider connected with the first inner diaphragm ring and the second inner diaphragm ring for dividing flow of a working fluid into each of the first diaphragm stage and the second diaphragm stage, the flow divider including: a body section having a substantially planar radially outer surface; and a pair of axially extending flanges extending from the body section, each of the flanges engaging with the first inner diaphragm ring and the second inner diaphragm ring, respectively; and a set of key members proximate a horizontal joint of the turbomachine diaphragm section between at least one of the pair of axially extending flanges and at least one of the first inner diaphragm ring or the second inner diaphragm ring.
Various other particular embodiments of the invention include a dual-flow turbomachine having: a first section having a first diaphragm stage with a first inner diaphragm ring and a first outer diaphragm ring; a second section opposing the first section, the second section having a second diaphragm stage with a second inner diaphragm ring and a second outer diaphragm ring; a flow divider connected with the first inner diaphragm ring and the second inner diaphragm ring for dividing flow of a working fluid into each of the first diaphragm stage and the second diaphragm stage, the flow divider including: a body section having a substantially planar radially outer surface; and a pair of axially extending flanges extending from the body section, each of the flanges engaging with the first inner diaphragm ring and the second inner diaphragm ring, respectively; and a set of key members proximate a horizontal joint of the dual-flow turbomachine between at least one of the pair of axially extending flanges and at least one of the first inner diaphragm ring or the second inner diaphragm ring.
Various other particular embodiments of the invention include a dual-flow turbomachine having: an inlet; a first section fluidly connected with the inlet and extending axially from the inlet in a first direction, the first section having a first diaphragm stage with a first inner diaphragm ring and a first outer diaphragm ring; a second section fluidly connected with the inlet and extending axially from the inlet in a second direction opposite the first direction, the second section having a second diaphragm stage with a second inner diaphragm ring and a second outer diaphragm ring; a flow divider connected with the first inner diaphragm ring and the second inner diaphragm ring for dividing flow of a working fluid from the inlet into each of the first diaphragm stage and the second diaphragm stage, the flow divider including: a body section having a substantially planar radially outer surface; and a pair of axially extending flanges extending from the body section, each of the flanges engaging with the first inner diaphragm ring and the second inner diaphragm ring, respectively, wherein the flow divider includes one of a rolled plate metal or a sheet metal; and a set of key members proximate a horizontal joint of the dual-flow turbomachine between each of the pair of axially extending flanges and each of the first inner diaphragm ring and the second inner diaphragm ring.
As used herein, the terms “axial” and/or “axially” refer to the relative position/direction of objects along axis A, which is substantially perpendicular to the axis of rotation of the turbomachine (in particular, the rotor section). As further used herein, the terms “radial” and/or “radially” refer to the relative position/direction of objects along axis (r), which is substantially perpendicular with axis A and intersects axis A at only one location. Additionally, the terms “circumferential” and/or “circumferentially” refer to the relative position/direction of objects along a circumference (C) which surrounds axis A but does not intersect the axis A at any location.
Turning to
In various embodiments, the turbomachine diaphragm section 2 can include a first diaphragm stage 8 in the first turbomachine section 4, and a second diaphragm stage 10 in the second turbomachine section 6. The first diaphragm stage 8 has a first inner diaphragm ring 12 and a first outer diaphragm ring 14. Between the first inner diaphragm ring 12 and the first outer diaphragm ring 14 sit a set of nozzles (or nozzle blades) 15, which help to direct working fluid toward the flow path of a first set of rotor buckets (not shown), as is known in the art. The second diaphragm stage 10 has a second inner diaphragm ring 16 and a second outer diaphragm ring 18. Between the second inner diaphragm ring 16 and the second outer diaphragm ring 18 sit a set of nozzles (or nozzle blades), which help to direct working fluid toward the flow path of a second set of rotor buckets (not shown), as is known in the art.
Also shown in
Returning to
It is understood that in various alternate embodiments, the radially inner wall 28 may be recessed such that each of the inner diaphragm rings 12, 16 do not include a radially inner wall 28. This alternate embodiment is depicted in phantom in
The flow divider 20 can include a body section 30, which in some cases can include a substantially planar radially outer surface 32, and a pair of axially extending flanges 34 each engaging with the first inner diaphragm ring 12 and the second inner diaphragm ring 16. In particular, one of the pair of axially extending flanges 34 can engage with (e.g., contact) each step 24 of the first inner diaphragm ring 12 and second diaphragm ring 16, respectively. As described herein, in various embodiments, the substantially planar radially outer surface 32 may serve as the contact surface for the flow of working fluid (e.g., steam) into the turbomachine. That is, the substantially planar radially outer surface 32 may serve to divert the flow of the working fluid toward the first turbomachine section 4 and second turbomachine section 6, respectively. The axially extending flanges 34 can extend from the body section 30 axially in opposite directions (toward the first turbomachine section 4 and second turbomachine section 6, respectively). As noted, these flanges 34 can contact the step of each of the inner diaphragm rings 12, 16. In various embodiments, these flanges 34 can each include a notch 35 (
Proximate the horizontal joint 22, the notch 35 (shown in phantom in
In various embodiments, the flow divider 20 can be formed from a rolled plate metal or a sheet metal. That is, the flow divider 20 can be formed without substantially machining or forging, and can be installed between the first diaphragm stage 8 in the first turbomachine section 4, and a second diaphragm stage 10. In some cases, where the flow divider 20 includes a sheet metal, the sheet metal has a thickness of at least 5 centimeters. The radially inner surface 46 of the flow divider 20 (opposite the radially outer surface 32) can be substantially free of machining in various embodiments, and in some embodiments, both the radially inward surface 46 and the radially outer surface 32 of the flow divider 20 are substantially free of machining.
It is understood that in various alternate embodiments, however, that a traditional protruding flow splitter, in the form of a peak, apex, flange, etc. can be integrated with the various embodiments of the flow divider 20. In these alternate embodiments, a peak or flange may be formed from a separate piece of metal and welded or brazed to the flow divider 20 circumferentially about the diaphragm section 2. This peak or flange could be used to aid in directing the flow of working fluid (steam) into the first diaphragm stage 8 and the second diaphragm stage 10.
The flow divider 20 shown and described according to the various embodiments of the invention can perform the flow dividing (or splitting) functions of conventional flow dividers used in turbomachinery, however, the flow divider 20 can require significantly less machining than conventional flow dividers. In some cases, the flow divider 20 includes surfaces which do not require machining. In some embodiments, the flow divider 20 can be formed of a rolled plate metal, a sheet metal, or other suitable metals which can perform the functions described herein. The flow divider 20 can be retained and restricted from rotation by one or more key members, which can be inserted in slots within the flow divider 20 and the diaphragm ring to restrict radial and/or circumferential movement of the flow divider 20.
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. It is further understood that the terms “front” and “back” are not intended to be limiting and are intended to be interchangeable where appropriate.
This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.
