Patent Description:
Turbine systems, such as steam turbine (ST) systems or gas turbine (GT) systems, are used in a wide variety of power generating systems. Turbines are typically constructed using one or more removable upper portions (e.g., upper shells or casings) to allow access to components within the turbine. The components within the turbine may include a large number of stationary and rotating components. Rotating components may include one or more wheels, shafts, etc., that rotate during the operation of the turbine. Stationary components may include one or more stationary wheels, diaphragms, support pads, deflectors, casing portions, bearings, etc., that remain stationary during operation of the turbine. Turbines may also include one or more lower portions (e.g., lower shells or casings) that generally serve as a support for the other turbine components, and may also assist in sealing the working fluid (e.g., steam or combusted fuel) path to prevent leakage. The upper casing is coupled to the lower casing to create the working fluid path.

Close tolerances among the various components of a turbine directly affect its efficiency. To illustrate, a large steam turbine weighing several tons may have tolerances for internal components measured in millimeters (mm), or in thousandths of an inch (mils). If stationary and rotating components are too close to one another, rubbing between the components may occur during operation. This rubbing makes it difficult to start the turbine after a servicing or overhaul, and generates excessive vibration. The rubbing may also wear the seals between the rotating and stationary components, and after the components have worn, excessive clearance will then exist in the areas in which rubbing occurred. If stationary and rotating components are too far apart from the other, working fluid leakage may occur between the components, reducing the efficiency of the turbine. Accordingly, great care is desirable when servicing or maintaining a turbine to ensure that the various components are aligned and positioned correctly.

During an offline servicing or overhaul of a turbine system, various components of a turbine may be accessed by removing the upper casing or casings, commonly referred to as "tops. " With the top-off, stationary and rotating components of the turbine may be inspected, adjusted, cleaned, repaired, replaced, and/or otherwise serviced. One type of inspection may determine the amount of displacement suffered by various components due to turbine operation. For example, certain stationary components might have shifted in alignment. Components that have become misaligned may then be realigned as a part of this inspection. Upon completion of the servicing or overhaul, the upper casing(s) may be replaced, and the turbine returned to operation. Unfortunately, an alignment problem commonly occurs when the top(s) are placed back on the lower casing. The upper casing(s) may weigh one ton or more, and the placement of these upper casing(s) onto the turbine may cause an additional amount of displacement or distortion among the previously-aligned components. Such displacement may generally be referred to herein as 'top-on displacement'. For example, a lower casing might spring up, or bow or sag between support points when in the top-off condition, and one or more stationary components connected to the lower casing, for example, the diaphragm portions, may shift. If the components are aligned with the top-off, they may shift when the tops are placed back on, and may actually shift out of alignment.

To address this problem, it is conventional practice to conduct a top-on/top-off alignment procedure. In this procedure, the upper casing(s) is/are first removed and the various components are removed and serviced, as needed. After these components are removed, the upper casing(s) are replaced, and the various component support positions within the couple casings are measured for position both vertically and transversely with respect to the centerline of the unit. Then, the upper casing(s) are once again removed, and a top-off line is measured. The top-off line measures the transverse and vertical positions of the internal components with the upper casing(s) and/or components removed. Then, these measurements are compared to determine an ideal position for the internal components when in the top-off condition. Then, with the upper casing(s) removed, the component support positions are adjusted to account for the top-on displacement. For example, a seat upon which a diaphragm portion sits may be adjusted to ensure the center of the diaphragm is aligned with the rotor axis. When the tops are placed back on, the components are then expected to shift into alignment. For example, a set of top-on and top-off measurements might show that a particular component shifts upwards <NUM> millimeters (mm) when the tops are placed on. This component may be aligned, in the top-off condition, to be <NUM> low to account for this rise.

The top-on/top-off procedure described above helps to ensure that various turbine components are in optimal alignment at the completion of the servicing. However, the top-on/top-off procedure is extremely time consuming. Many hours are required to perform the various measurements, as well as removing and replacing the upper casing(s) twice, resulting in higher costs for personnel time and a greater amount of lost revenue due to the turbine being offline. The process can be further complicated because, when assembled without the rotor and/or other internal components, the full turbine casing is not fully representative of the top-on conditions because some of the internal components, e.g., the diaphragms and carriers, associated with the upper casing and the rotor are not present. The current process can therefore be inaccurate. Consequently, the alignment process may need to be repeated, which adds to costs. One approach to address these issues measures right and left component supports and/or inner shell displacements in a top-off situation, and calculates predicted vertical and/or transverse offset values that are percentages of the measured displacements for adjustment of components. While this approach eliminates the repetitive assembly, it does not consider the complete top-on situation, and can be inaccurate.

<CIT> discloses a method of aligning a component within a turbine casing, the turbine casing including an upper casing and a lower casing configured to collectively surround a rotor, the rotor having a rotor axis. The method comprises: for at least one primary axial location along the rotor axis and at one or both sides of the turbine casing at each primary axial location: with the upper casing coupled to the lower casing in a top-on position (in a temporarily assembled state), measuring a first location of a first reference point at a first optical target coupled to an outer surface of a horizontal joint flange of the lower casing. The method further comprises: with at least the upper casing removed from the lower casing in a top-off position, measuring a third location of the first reference point at the first optical target.

A first aspect of the invention provides a method of aligning a component within a turbine casing, the turbine casing including an upper casing and a lower casing configured to collectively surround a rotor, the rotor having a rotor axis, the method comprising: for at least one primary axial location along the rotor axis and at one or both sides of the turbine casing at each primary axial location: with the upper casing coupled to the lower casing in a top-on position, measuring: a first location of a first reference point at a first optical target coupled to an outer surface of a horizontal joint (HJ) flange of the lower casing, and a second location of a second reference point at a second optical target coupled to the outer surface of the HJ flange of the lower casing and vertically spaced from the first optical target; with at least the upper casing removed from the lower casing in a top-off position, measuring: a third location of the first reference point at the first optical target, a fourth location of the second reference point at the second optical target, a fifth location of a third reference point on an upper surface of the horizontal joint (HJ) flange of the lower casing, the third reference point having a known spatial relation to a component support position of the component in the lower casing at the respective primary axial location, and a sixth location of a fourth reference point on the upper surface of the HJ flange of the lower casing, the fourth reference point spaced from the third reference point on the upper surface of the HJ flange of the lower casing; calculating a prediction offset value for the component support position in the top-on position based on at least the first, second, third, fourth, fifth and sixth locations and an inner radius of the lower casing; and adjusting the component support position in the turbine casing by the prediction offset value, wherein an alignment of the component positioned at the component support position is improved relative to the rotor axis upon replacing the upper casing to the top-on position.

A second aspect of the invention provides a system for aligning a component within a turbine casing, the turbine casing including an upper casing and a lower casing configured to collectively surround a rotor, the rotor having a rotor axis, the system comprising: a measurement module configured to: for at least one primary axial location along the rotor axis and at one or both sides of the turbine casing at each primary axial location: with the upper casing coupled to the lower casing in a top-on position, receive a measurement of: a first location of a first reference point at a first optical target coupled to an outer surface of a horizontal joint (HJ) flange of the lower casing, and a second location of a second reference point at a second optical target coupled the outer surface of the HJ flange of the lower casing and vertically spaced from the first optical target; with at least the upper casing removed from the lower casing in a top-off position, receive a measurement of: a third location of the first reference point at the first optical target, a fourth location of the second reference point at the second optical target, a fifth location of a third reference point on an upper surface of the horizontal joint (HJ) flange of the lower casing, the third reference point having a known spatial relation to a component support position of the component in the lower casing at the respective primary axial location, and a sixth location of a fourth reference point on the upper surface of the HJ flange of the lower casing, the fourth reference point spaced from the third reference point on the upper surface of the HJ flange of the lower casing; and a calculation module configured to: calculate a prediction offset value for the component support position in the top-on position based on at least the first, second, third, fourth, fifth and sixth locations and an inner radius of the lower casing, and indicate an adjustment for the component support position in the turbine casing at the at least one primary axial location based on the prediction offset value.

The illustrative aspects of the present invention are designed to solve the problems herein described and/or other problems not discussed.

These and other features of this disclosure 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 disclosure are not to scale.

As an initial matter, in order to clearly describe the current disclosure it will become necessary to select certain terminology when referring to and describing relevant machine components within a turbine system. When doing this, if possible, common industry terminology will be used and employed in a manner consistent with its accepted meaning. Unless otherwise stated, such terminology should be given a broad interpretation consistent with the context of the present application and the scope of the appended claims. Those of ordinary skill in the art will appreciate that often a particular component may be referred to using several different or overlapping terms. What may be described herein as being a single part may include and be referenced in another context as consisting of multiple components. Alternatively, what may be described herein as including multiple components may be referred to elsewhere as a single part.

In addition, several descriptive terms may be used regularly herein, and it should prove helpful to define these terms at the onset of this section. These terms and their definitions, unless stated otherwise, are as follows. As used herein, "downstream" and "upstream" are terms that indicate a direction relative to the flow of a fluid, such as the working fluid through the turbine system or, for example, the flow of air through the combustor or coolant through one of the turbine system's component systems. The term "downstream" corresponds to the direction of flow of the fluid, and the term "upstream" refers to the direction opposite to the flow. The terms "forward" and "aft," without any further specificity, refer to directions, with "forward" referring to the front or compressor end of the engine, and "aft" referring to the rearward or turbine end of the engine. It is often required to describe parts that are at differing radial positions with regard to a center axis. The term "radial" refers to movement or position perpendicular to an axis. In cases such as this, if a first component resides closer to the axis than a second component, it will be stated herein that the first component is "radially inward" or "inboard" of the second component. If, on the other hand, the first component resides further from the axis than the second component, it may be stated herein that the first component is "radially outward" or "outboard" of the second component. The term "axial" refers to movement or position parallel to an axis, e.g., the turbine rotor axis. Finally, the term "circumferential" refers to movement or position around an axis. It will be appreciated that such terms may be applied in relation to the center axis of the turbine.

Where an element or layer is referred to as being "on," "engaged to," "disengaged from," "connected to," or "coupled to" another element or layer, it may be directly on, engaged, connected or coupled to the other element or layer, or intervening elements or layers may be present.

As indicated above, the disclosure provides a method and system for aligning a component within a turbine casing, and a related turbine casing. In a top-on position, a location of the optical target and another, vertically spaced optical target on a horizontal joint (HJ) flange of the lower casing are measured at one or more primary axial locations. After removing at least the upper casing, the optical targets' locations are measured again, and the locations of a pair of reference points on an upper surface of the HJ flange, are measured. A prediction offset value is calculated for the component support position in the top-on position based on at least the measured locations. The prediction offset value may include a number of calculated adjustments. In one example, a tilt angle of the lower casing and a rotation angle of the lower casing can be calculated, and a vertical adjustment made based on both. In another example, a horizontal adjustment can be calculated based on the horizontal shift of the lower casing from the top-on to the top-off position. In another example, an HJ flange surface distortion can be identified by superimposing reference lines of the HJ flange surfaces and identifying any gaps at an inner or outer location of mating of the surfaces with the prediction offset value including a correction based on the surface distortion. Similar prediction offset values can be calculated for other secondary axial locations that include only one optical target. In any event, the component support position at a variety of axial locations may be adjusted by the prediction offset value to improve alignment at each axial location. The method and system reduce the lifting required and can address practically all of the alignment issues.

Referring to the drawings, <FIG> shows a perspective partial cut-away illustration of an illustrative turbine system in the form of a steam turbine (ST) system <NUM>. ST system <NUM> includes a rotor <NUM> that includes a turbine rotor <NUM> and a plurality of axially spaced rotor wheels <NUM>. Turbine rotor <NUM> has a rotor axis A. A plurality of rotating turbine blades <NUM> are mechanically coupled to each rotor wheel <NUM>. More specifically, turbine blades <NUM> are arranged in rows that extend circumferentially around each rotor wheel <NUM>. A plurality of stationary vanes <NUM> extends circumferentially around turbine rotor <NUM>, and the vanes are axially positioned between adjacent rows of turbine blades <NUM>. Stationary vanes <NUM> cooperate with turbine blades <NUM> to form a stage and to define a portion of a steam flow path through ST system <NUM>. In one embodiment of the present disclosure, as shown in <FIG>, ST system <NUM> comprises five stages. The five stages are referred to as L0, L1, L2, L3 and L4. Stage L4 is the first stage and is the smallest (in a radial direction) of the five stages. Stage L3 is the second stage and is the next stage in an axial direction. Stage L2 is the third stage and is shown in the middle of the five stages. Stage L1 is the fourth and next-to-last stage. Stage L0 is the last stage and is the largest (in a radial direction). It is to be understood that five stages are shown as one example only, and each turbine system may have more or less than five stages. Also, as will be described herein, the teachings of the invention do not require a multiple stage turbine.

In operation, a working fluid, here steam, <NUM> enters an inlet <NUM> of ST system <NUM> and is channeled through stationary vanes <NUM>. Vanes <NUM> direct steam <NUM> downstream against turbine blades <NUM>. Steam <NUM> passes through the remaining stages imparting a force on turbine blades <NUM> causing turbine rotor <NUM> to rotate. At least one end of ST system <NUM> may extend axially away from rotor <NUM> and may be attached to a load or machinery (not shown) such as, but not limited to, a generator, and/or another turbine.

While embodiments of the disclosure will be described relative to ST system <NUM>, it will be readily understood that the teachings of the disclosure are applicable to a variety of turbine systems and/or other industrial machines having heavy mating casings or parts that require component alignment.

As shown in a side perspective view of <FIG>, ST system <NUM> includes a turbine casing <NUM> including a lower casing <NUM> having a lower horizontal joint (HJ) flange <NUM>, and an upper casing <NUM> having an upper horizontal joint (HJ) flange <NUM>. (Note, <FIG> shows ST system <NUM> with any insulation and much of its piping removed. ) Lower and upper casings <NUM>, <NUM> may each represent any degree of a <NUM>° casing that collectively surround turbine rotor <NUM>. That is, upper casing(s) <NUM> and lower casing(s) <NUM> are collectively configured to surround turbine rotor <NUM> (<FIG>) and turbine blades <NUM> (<FIG>) coupled to the turbine rotor. The disclosure will be described relative to a single upper casing <NUM> and single lower casing <NUM>, it will be appreciated by those with skill in the art that the teachings are applicable to turbine systems having numerous upper and/or lower casings. In any event, upper casing <NUM> and lower casing <NUM> are configured to collectively surround turbine rotor <NUM> and turbine blades <NUM> coupled to turbine rotor <NUM>. Upper casing <NUM> and lower casing <NUM> can be attached, for example, by fasteners, at respective HJ flanges <NUM>, <NUM>. HJ flanges <NUM>, <NUM> extend radially outward from rounded portions of casings <NUM>, <NUM> to create connection flanges. While named "horizontal joint" flanges, as understood in the art, the HJ flanges <NUM>, <NUM> may diverge from horizontal. Each casing <NUM>, <NUM> has an inner radius (IR) (<FIG>) used for operations according to embodiments of the disclosure. Inner radius (IR) may vary depending on the prediction offset value being calculated. For example, inner radius (IR) may be from rotor axis A to an inner surface of each casing <NUM>, <NUM>, from rotor axis A to an outer surface of component <NUM>, or from rotor axis to some part of a relevant component support position <NUM>.

Typically, upper casing <NUM> is removed during maintenance to expose turbine rotor <NUM> and internal components of ST system <NUM>. Upper casing <NUM> can be removed by removing any insulation and external piping (not shown), removing fasteners to lower casing <NUM>, and lifting it away with a crane, e.g., a heavy lift crane. Components within lower casing <NUM> can then be serviced. In many instances, the components may also be removed, serviced and replaced, requiring alignment thereof relative to casings <NUM>, <NUM> prior to re-use. Components that may require alignment upon replacement of upper casing <NUM> may include, for example, a diaphragm portion <NUM> (<FIG>), an inner casing portion <NUM> (<FIG>) and one or more stationary nozzle portions <NUM> (<FIG>). It is understood that the prior list of components is not comprehensive and a wide variety of components may require alignment.

<FIG> shows a top down view in a top-off position of an illustrative component <NUM> in the form of a diaphragm <NUM>. <FIG> shows an occupied diaphragm support position <NUM> having a diaphragm <NUM> therein; and a component (diaphragm) support position 124E emptied of a respective diaphragm. <FIG> shows a partial cross-sectional view of an illustrative diaphragm <NUM> (shown transparent) in a component support position <NUM> in one side of lower casing <NUM>. As understood, any number of diaphragms <NUM> are axially spaced within casings <NUM>, <NUM> and extend within an inner radius of each casing <NUM>, <NUM> to interact with turbine blades <NUM> (<FIG>). Diaphragms <NUM> of lower casing <NUM> and upper casing <NUM> (not shown) mate at their respective circumferential ends <NUM> (<FIG>) to create a working fluid path with turbine blades <NUM> (<FIG>). As illustrated, each diaphragm <NUM> has an extension <NUM> at circumferential ends <NUM> (<FIG>) thereof that is supported by component support position <NUM>. In the example shown, component support position <NUM> may include a shim <NUM> fastened to a ledge <NUM> (<FIG> only). More particularly, component support position <NUM> may include ledge <NUM> (<FIG> only) on an inner radius of lower casing <NUM>, and shim <NUM> may be positioned thereon to support extension <NUM> of diaphragm <NUM>. Shim <NUM> and/or ledge <NUM> can be adjusted to align diaphragm <NUM> relative to turbine casing <NUM>, e.g., after service of ST system <NUM> (<FIG>). For example, shim <NUM> can be adjusted by increasing or decreasing its height relative to ledge <NUM> to adjust a vertical height of component <NUM>, i.e., to raise or lower diaphragm <NUM>. In addition or alternatively, shim <NUM> can be adjusted to change an angle (α) of an upper surface <NUM> thereof. In addition or alternatively, edge <NUM> can be adjusted similarly to shim <NUM>. While component <NUM> has been illustrated and described herein as a diaphragm <NUM>, it is understood that the teachings of the disclosure are applicable to a wide variety of alternative components <NUM> within turbine casing <NUM>. For example, as noted, component <NUM> may include at least one of a diaphragm portion <NUM> (<FIG>) (of diaphragm <NUM>), an inner casing portion <NUM> (<FIG>) and one or more stationary nozzle portions <NUM> (<FIG>). Further, while component support position <NUM> has been described as a ledge and shim arrangement, it is understood that a shim <NUM> may not be necessary, and ledge <NUM> could be adjusted alone. Further, it is emphasized that component support position <NUM> may take a variety of alternative forms other than a ledge and shim arrangement, and may include any form of support for a component <NUM>. Component support position <NUM> may also be located at a different location than indicated in <FIG>, depending on the component. The component support position can also be directly on HJ flange <NUM>, <NUM>. The adjustment may be made by means of an adjusting screw or bolt.

In accordance with the invention, parts of turbine casing <NUM> are provided with a number of selected reference points (RP) that can be used to calculate a prediction offset value that can be employed to adjust a component support position <NUM> to improve alignment of component <NUM> positioned at component support position <NUM> relative to rotor axis A upon replacing upper casing <NUM> to the top-on position.

As shown in <FIG> and <FIG>, turbine casing <NUM> includes a plurality of first optical targets <NUM>. Each first optical target <NUM> is positioned at one of a plurality of axial locations relative to a radially facing outer surface <NUM> of lower HJ flange <NUM> of lower casing <NUM>. First optical targets <NUM> are coupled to radially facing outer surface <NUM> of lower HJ flange <NUM>. Each first optical target <NUM> may include any now known or later developed optical target capable of detection using an appropriate measurement system. In one non-limited example, first optical target(s) <NUM> may include a spherically mounted retroreflector (SMR) adapter coupled to radially facing outer surface <NUM> of lower HJ flange <NUM> of lower casing <NUM>. First optical target(s) <NUM> may be coupled to radially facing outer surface <NUM> in any now known or later developed manner, e.g., welding, fasteners, etc. In one example, a measurement system <NUM> for measuring a location of optical target(s) <NUM> may include, for example, a laser measurement system such as a Vantage model laser tracker available from FARO Corp. of Lake Mary, FL, or a model AT401 laser tracker available from Leica Geosystems Inc. of Norcross, GA. Measurement system <NUM> may be operatively coupled to an alignment system <NUM>, described herein. While a laser measurement system has been listed herein as an example, it is understood that wide variety of alternative measurement systems are available that are capable of the locating a reference point in three-dimensional space. Measurement system <NUM> may include but is not limited to: infrared, radar, etc..

For purposes that will be described herein, turbine casing <NUM> also includes a second optical target <NUM> positioned at one or more of axial locations with first optical targets <NUM>. Axial locations that include both optical targets <NUM>, <NUM> are referred to hereafter as "primary axial locations," while those with only first optical target <NUM> are referred to hereafter as "secondary axial locations. " As shown best in <FIG>, each second optical target <NUM> is vertically spaced from a respective first optical target <NUM>, e.g., on radial facing outer surface <NUM> of lower HJ flange <NUM>, by a distance D1. This vertical spacing D1 may vary depending on, for example, the size of lower HJ flange <NUM>. The vertical spacing D1 is predefined such that a spatial relationship between optical targets <NUM>, <NUM> at the selected primary axial locations is known. In one non-limited example, second optical targets <NUM> may also include an SMR adapter coupled to an outer surface of lower HJ flange <NUM> of lower casing <NUM>. Second optical target(s) <NUM> may be coupled to the outer surface in any now known or later developed manner, e.g., welding, fasteners, etc. Second optical targets <NUM> are coupled to radially facing outer surface <NUM> of lower HJ flange <NUM>. In the example shown, three second optical targets <NUM> are shown, resulting in three primary axial locations, but any number may be employed. As illustrated, first optical targets <NUM> alone may also be positioned on lower HJ flange <NUM> at a number of secondary axial locations at which no second optical target <NUM> is present. If reference is made to simply "axial location" it refers to any axial location - primary and/or secondary axial locations, or other axial locations. The purposes of optical targets <NUM>, <NUM> and the primary and secondary axial locations will be described herein.

<FIG> shows a number of reference points that can be used to identify issues that can impact any necessary adjustment to component support position <NUM>. The locations of the reference points relative to lower HJ flange <NUM> and/or upper HJ flange <NUM> may be predefined based on the geometry at the desired axial location of lower casing <NUM>, and can be measured by measurement system <NUM> according to embodiments of the disclosure. As will be described, the locations can be used by alignment system <NUM> to calculate a prediction offset value for one or more component support positions <NUM> in the top-on position. Adjusting component support position <NUM> in turbine casing <NUM> (<FIG>) by the prediction offset value improves an alignment of component <NUM> (<FIG>) positioned at component support position <NUM> relative to rotor axis A upon replacing upper casing <NUM> to the top-on position. In the disclosure, a 'reference point' indicates a fixed position on the upper or lower casing, e.g., of an optical target or other selected position, while a 'location of a reference point X' indicates a changeable, three dimensional position of a reference point X, e.g., as measured by measurement system <NUM>. The locations will be numbered, i.e., first, second, third, etc., for differentiation purposes. Note, each reference point may have a number of locations. In any event, locations may be indicated by any now known or later developed three dimensional coordinate system, e.g., using measurement system <NUM> as an origin. Measurement system <NUM>, as noted, may include any appropriate measurement system for measuring locations of reference points on casings <NUM>, <NUM>, e.g., using lasers. Alignment system <NUM> may receive the locations of the reference points at measurement module <NUM> (<FIG>) where calculation module <NUM> (<FIG>) calculates the prediction offset value.

As shown in <FIG>, the following illustrative reference points are defined at each selected primary axial location: a first reference point RP1 at first optical target <NUM> coupled to an outer surface <NUM> (<FIG>) of lower HJ flange <NUM>; a second reference point RP2 at second optical target <NUM> coupled to outer surface <NUM> (<FIG>) of lower HJ flange <NUM> and vertically spaced from first optical target <NUM> (<FIG>); a third reference point RP3 on upper surface <NUM>; and a fourth reference point RP4 on upper surface <NUM>. As will be described, upper casing <NUM> may include a number of reference points thereon including, for example, a fifth reference point RP5 on a lower (as drawn) surface <NUM> of upper HJ flange <NUM> and a sixth reference point RP6 on lower surface <NUM> of upper HJ flange <NUM>. In addition, secondary axial locations may also include reference points. As noted, secondary axial locations do not include second optical target <NUM> coupled to outer surface <NUM> (<FIG>) of lower HJ flange <NUM>. As shown in <FIG>, secondary axial locations may include seventh, eighth and ninth reference points RP7, RP8 and RP9. As will be further described, seventh, eighth and ninth reference points RP7, RP8 and RP9 correspond in function to first, third and fourth reference points (RP1, RP3, RP4) at primary axial locations.

In accordance with embodiments of the disclosure, at least one of the reference points has a known spatial relationship to component support position <NUM> such that a change in position of the reference point, i.e., as calculated in the form of the prediction offset value, can be used to adjust component support position <NUM> to provide the necessary change in position to component <NUM> (<FIG> and <FIG>) to ensure alignment thereof in the top-on position. In the example shown, third reference point RP3 has a known spatial relationship with component support position <NUM>, e.g., ledge <NUM> and/or shim <NUM>. The spatial relationship may be in any form. That is, a direct relationship in which third reference point RP3 may have a defined vertical and/or radial offset from component support position <NUM>, and/or an indirect relationship in which third reference point RP3 and component support position <NUM> each having a known relationship to another point, e.g., inner edge <NUM> of lower casing <NUM>. In any event, the spatial relationship can be used to calculate changes for component support position <NUM>. At secondary axial locations, seventh reference point RP7 (<FIG>) may provide the same function as third reference point RP3 for primary axial locations, i.e., it has a known spatial relationship with component support position <NUM> at the respective secondary axial location.

As observed in <FIG>, spatial relationships between the reference points can be defined based on the known (expected) geometry of lower HJ flange <NUM> at each axial location. That is, the reference points can be used to define an expected spatial relationship for each axial location as lower HJ flange <NUM> and/or upper HJ flange <NUM> changes along axial cross-sections. For example, distance D1 between first and second reference points RP1, RP2 is defined. In addition, each axial location may have a different third reference point RP3 and fourth reference point RP4 and/or fifth reference point RP5 and sixth reference point RP6 that are selected, for example, to avoid structure at a given axial location, e.g., cooling channels as shown in <FIG>. Regardless, each set of third and fourth reference points RP3, RP4 and each set of fifth reference points RP5, RP6 may have defined spatial relationships with each other and other reference points, which can be verified through measurement in the top-off position. For example, a defined distance D2 between third and fourth reference points RP3 and RP4 (and RP5 and RP6) is defined and can be more precisely verified by measurement for each axial location. Further, fourth reference point RP4 may be a defined distance D3 from outer edge <NUM> of lower HJ flange <NUM>, and first reference point RP1 (i.e., first optical target <NUM>) may be a defined distance D4 from outer edge <NUM> of lower HJ flange <NUM>. As a result, a triangular spatial relationship <NUM> (see differently shaded triangle in <FIG>) between first reference point RP1, third reference point RP3 and fourth reference point RP4, is known and can be verified through measurement. Fifth location L5 of third reference point RP3 on upper surface <NUM> of lower HJ flange <NUM>, sixth location L6 of fourth reference point RP4 on upper surface <NUM> of lower HJ flange <NUM>, and third location L3 of first reference point RP1 at first optical target <NUM> in the top-off position, may be measured at a selected axial location to identify (verify) triangular spatial relationship <NUM>. Consequently, as will be described, differences between an actual location of third reference point RP3 as measured in the top-off position and a predicted top-on location thereof based on a translation of triangular spatial relationship <NUM> to the top-on position (i.e., based on a location of the first reference point RP1 in the top-on position), can be used to calculate at least one form of the prediction offset value. Similar relationships exist for seventh, eighth, and ninth reference points RP7, RP8 and RP9 (<FIG>) at secondary axial locations.

As noted, <FIG> also shows upper casing <NUM> with a number of reference points thereon (internal components not shown for upper casing <NUM>). For example, upper casing <NUM> may include fifth reference point RP5 on lower (as drawn) surface <NUM> of upper HJ flange <NUM> and sixth reference point RP6 on lower surface <NUM> of upper HJ flange <NUM>. In a top-on position, fifth reference point RP5 is aligned with third reference point RP3, and sixth reference point RP6 is aligned with fourth reference point RP4. Therefore, fifth and sixth reference points RP5 and RP6 may be distance D2 apart. Fifth and sixth reference points RP5 and RP6 locations may also be known relative to edges of upper HJ flange <NUM>.

Reference points are defined relative to casings <NUM>, <NUM> by optical targets <NUM>, <NUM>, or by any other mechanism by which measurement system <NUM> can measure their location, e.g., marks or objects on a surface detectable by measurement system <NUM>, temporary measurement targets placed at the reference point (e.g., optical target, reflective tape, scribe marks, stamped marks, etc.), etc..

<FIG> show schematic cross-sectional views of possible HJ flange <NUM>, <NUM> scenarios that may occur during a maintenance operation in which upper casing <NUM> is removed from lower casing <NUM>, i.e., to a top-off position. The scenarios illustrated can occur at any axial location, and at one or both sides of lower casing <NUM>. Each scenario may impact alignment of components <NUM> (<FIG>) within turbine casing <NUM> differently, and can be addressed according to the methodology described herein. For purposes of description, <FIG> illustrate HJ flanges <NUM>, <NUM> from a perspective in which turbine rotor axis A is to the left of the side shown. As will be described, rotor axis A acts as a coordinate system origin for the methodology described. For brevity, rotor axis A is only shown in <FIG>; however, a reference line RL at which flanges <NUM>, <NUM> could potentially meet has been provided. Most of the parts that curve away for casings <NUM>, <NUM> have been omitted for clarity. It is appreciated that the diametrically opposing side of each casing <NUM>, <NUM> from that shown may have similar, symmetrical positioning.

As understood the in the art, when HJ flanges <NUM>, <NUM> are separated, lower casing <NUM> and lower HJ flange <NUM> may spring upwardly or bow, and upper casing <NUM> and upper HJ flange <NUM> may drop or spring downwardly. As this occurs, lower HJ flange <NUM> rotates about rotor axis A, changing vertical positioning. Further, lower HJ flange <NUM> may tilt inwardly, tilt outwardly or simply move vertically. Similarly, upper HJ flange <NUM> may tilt inwardly, tilt outwardly or simply move vertically. In addition, an upper surface <NUM> of lower HJ flange <NUM>, and a lower surface <NUM> of upper HJ flange <NUM> may distort upon separation, i.e., the surfaces become non-planar. In this latter case, when casings <NUM>, <NUM> are mated together again, surfaces <NUM>, <NUM> may not meet in a surface-to-surface mating fashion, e.g., planar surface to planar surface, which may cause edges of casings <NUM>, <NUM> to not close, creating a leak. While casings <NUM>, <NUM> can be forcibly brought into planar engagement by way of fasteners that couple them together, the meeting of edges rather than surfaces, e.g., inner edges <NUM> or outer edges <NUM>, may impact the alignment of component <NUM> (<FIG>) inside the casings.

While <FIG> show schematic cross-sectional views of possible HJ flange <NUM>, <NUM> scenarios that may occur, they do not necessarily show the rotation of lower casing <NUM> about rotor axis A. Calculation of a prediction offset value (vertical adjustment) based on the rotation, among other things, will be illustrated elsewhere in the drawings.

<FIG> shows an illustrative scenario <NUM> in which both HJ flanges <NUM>, <NUM> are parallel, i.e., surfaces <NUM>, <NUM> thereof are parallel to one another and reference line (RL). If brought together, inner edges <NUM> would meet nearly simultaneously with outer edges <NUM>, so the joint would not be open on either side. In this case, casings <NUM>, <NUM> have not tilt, they simply separated from one another vertically.

<FIG> shows an illustrative scenario <NUM> in which HJ flanges <NUM>, <NUM> are not parallel and have tilt such that, if brought together, inner edges <NUM> would be initially separated, and outer edges <NUM> would touch first, leaving the joint open on the inside (left side, as shown). In the scenario illustrated, lower HJ flange <NUM> tilt counterclockwise, and upper HJ flange <NUM> tilt clockwise.

<FIG> shows an illustrative scenario <NUM> in which both HJ flanges <NUM>, <NUM> are not parallel and have tilt such that, if brought together, outer edges <NUM> would be initially separated, and inner edges <NUM> would touch first, leaving the joint open on the outside (right side, as shown). In the scenario illustrated, lower HJ flange <NUM> tilt clockwise, and upper HJ flange <NUM> tilt counterclockwise.

<FIG> shows an illustrative scenario <NUM> in which HJ flange <NUM>, <NUM> are not parallel and lower HJ flange <NUM> has tilt such that, if brought together, inner edges <NUM> would be initially separated, and outer edges <NUM> would touch first, leaving the joint open on the inside (left side, as shown). In the scenario illustrated, lower HJ flange <NUM> tilt counterclockwise, and upper HJ flange <NUM> did not tilt and remains parallel, e.g., to reference line RL.

<FIG> shows an illustrative scenario <NUM> in which HJ flanges <NUM>, <NUM> are not parallel and lower HJ flange <NUM> has tilt such that, if brought together, inner edges <NUM> would be initially separated, and inner edges <NUM> would touch first, leaving the joint open on the outside (right side, as shown). In the setting illustrated, lower HJ flange <NUM> tilt clockwise, and upper HJ flange <NUM> did not tilt and remains parallel, e.g., to reference line RL.

<FIG> shows an illustrative scenario <NUM> in which both HJ flanges <NUM>, <NUM> are parallel and both have tilt. Here, however, if brought together, inner edges <NUM> would meet nearly simultaneously with outer edges <NUM>, so the joint would not be open on either side. In the scenario illustrated, lower HJ flange <NUM> tilt clockwise, and upper HJ flange <NUM> tilt clockwise.

<FIG> shows an illustrative scenario <NUM> in which both HJ flanges <NUM>, <NUM> are parallel and both have tilt. Here, similar to <FIG>, if brought together, inner edges <NUM> would meet nearly simultaneously with outer edges <NUM>, so the joint would not be open on either side. In the scenario illustrated, lower HJ flange <NUM> tilt counterclockwise, and upper HJ flange <NUM> tilt counterclockwise.

Another issue that can occur in any of the previous scenarios is that surfaces <NUM>, <NUM> may not be planar after casing <NUM>, <NUM> separation. In this setting, inner edges <NUM> may not be in the same plane as outer edge <NUM>, or other point(s) therebetween may make the surfaces non-planar.

Certain aspects of the invention are embodied as an alignment system <NUM>, method or computer program product. Accordingly, the present disclosure may take the form of an entirely hardware embodiment, an entirely software embodiment (including firmware, resident software, micro-code, etc.) or an embodiment combining software and hardware aspects that may all generally be referred to herein as a "circuit," "module" or "system. " Furthermore, the present disclosure may take the form of a computer program product embodied in any tangible medium of expression having computer-usable program code embodied in the medium.

Any combination of one or more computer usable or computer readable medium(s) may be utilized. More specific examples (a non-exhaustive list) of the computer-readable medium would include the following: an electrical connection having one or more wires, a portable computer diskette, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a transmission media such as those supporting the Internet or an intranet, or a magnetic storage device. In the context of this document, a computer-usable or computer-readable medium may be any medium that can contain, store, communicate, propagate, or transport the program for use by or in connection with the instruction execution system, apparatus, or device. The computer-usable medium may include a propagated data signal with the computer-usable program code embodied therewith, either in baseband or as part of a carrier wave. The computer usable program code may be transmitted using any appropriate medium, including but not limited to wireless, wireline, optical fiber cable, RF, etc..

Computer program code for carrying out operations of the present disclosure may be written in any combination of one or more programming languages, including an object oriented programming language such as Java, Smalltalk, C++ or the like and conventional procedural programming languages, such as the "C" programming language or similar programming languages.

The present disclosure is described below with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems) and computer program products according to embodiments of the disclosure.

These computer program instructions may also be stored in a computer-readable medium that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable medium produce an article of manufacture including instruction means which implement the function/act specified in the flowchart and/or block diagram block or blocks.

The computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide processes for implementing the functions/acts specified in the flowchart and/or block diagram block or blocks.

<FIG> shows an illustrative environment <NUM> for alignment system <NUM>. To this extent, environment <NUM> includes a computer infrastructure <NUM> that can perform the various process steps described herein for alignment system <NUM>. In particular, computer infrastructure <NUM> is shown including a computing device <NUM> that comprises alignment system <NUM>, which enables computing device <NUM> to receive measurements and calculate prediction offset value for adjustments for casings <NUM>, <NUM>, i.e., by performing the process steps of the disclosure.

Computing device <NUM> is shown including a memory <NUM>, a processor (PU) <NUM>, an input/output (I/O) interface <NUM>, and a bus <NUM>. Further, computing device <NUM> is shown in communication with an external I/O device/resource <NUM> and a storage system <NUM>. As is known in the art, in general, processor <NUM> executes computer program code, such as alignment system <NUM>, that is stored in memory <NUM> and/or storage system <NUM>. While executing computer program code, processor <NUM> can read and/or write data, such as alignment system <NUM>, to/from memory <NUM>, storage system <NUM>, and/or I/O interface <NUM>. Bus <NUM> provides a communications link between each of the components in computing device <NUM>. I/O device <NUM> can comprise any device that enables a user to interact with computing device <NUM> or any device that enables computing device <NUM> to communicate with one or more other computing devices. Input/output devices (including but not limited to keyboards, displays, pointing devices, etc.) can be coupled to the system either directly or through intervening I/O controllers.

In any event, computing device <NUM> can comprise any general purpose computing article of manufacture capable of executing computer program code installed by a user (e.g., a personal computer, server, handheld device, etc.). However, it is understood that computing device <NUM> and alignment system <NUM> are only representative of various possible equivalent computing devices that may perform the various process steps of the disclosure. To this extent, in other embodiments, computing device <NUM> can comprise any specific purpose computing article of manufacture comprising hardware and/or computer program code for performing specific functions, any computing article of manufacture that comprises a combination of specific purpose and general purpose hardware/software, or the like. In each case, the program code and hardware can be created using standard programming and engineering techniques, respectively.

Similarly, computer infrastructure <NUM> is only illustrative of various types of computer infrastructures for implementing the disclosure. For example, in one embodiment, computer infrastructure <NUM> comprises two or more computing devices (e.g., a server cluster) that communicate over any type of wired and/or wireless communications link, such as a network, a shared memory, or the like, to perform the various process steps of the disclosure. When the communications link comprises a network, the network can comprise any combination of one or more types of networks (e.g., the Internet, a wide area network, a local area network, a virtual private network, etc.). Network adapters may also be coupled to the system to enable the data processing system to become coupled to other data processing systems or remote printers or storage devices through intervening private or public networks. Modems, cable modem and Ethernet cards are just a few of the currently available types of network adapters. Regardless, communications between the computing devices may utilize any combination of various types of transmission techniques.

As previously mentioned and discussed further below, alignment system <NUM> enables computer infrastructure <NUM> to calculate prediction offset value(s) that can be used to make adjustments to improve alignment of components <NUM> (<FIG>) within casings <NUM>, <NUM> (<FIG>). To this extent, alignment system <NUM> is shown including a measurement module <NUM>, and a calculation module <NUM>. Other system components <NUM> may also be provided. Operation of each of these systems is discussed further below. However, it is understood that some of the various systems shown in <FIG> can be implemented independently, combined, and/or stored in memory for one or more separate computing devices that are included in computer infrastructure <NUM>. Further, it is understood that some of the systems and/or functionality may not be implemented, or additional systems and/or functionality may be included as part of environment <NUM>.

Alignment system <NUM> may be geographically located on-site, local to turbine system <NUM>, or it may be geographically remote from turbine system <NUM>, e.g., in a centralized turbine system control center.

Referring to the flow diagram of <FIG>, a method of aligning a component <NUM> (<FIG>) within turbine casing <NUM> (<FIG>) will now be described. <FIG> shows a perspective view of an illustrative lower casing <NUM> with a number of axial locations highlighted with cross-sectional planes, <FIG> shows an enlarged cross-sectional view of one side of HJ flanges <NUM>, <NUM> in a top-on position of the turbine casing, <FIG> shows an enlarged cross-sectional view of one side of HJ flanges <NUM>, <NUM> in an illustrative top-off position of the turbine casing, and <FIG> shows an enlarged, schematic cross-sectional view of an illustrative HJ flange <NUM> show potential adjustments. In <FIG>, rotor axis A is to the left (off the page), as illustrated. As will be described, a number of processes occur with lower casing <NUM> and upper casing <NUM> attached in a top-on position, as shown in <FIG> and <FIG>, and a number of processes occur with lower casing <NUM> and upper casing <NUM> in a de-coupled, top-off position, as shown in for example, <FIG>, <FIG> and <FIG>.

Processes P10-P22 are carried out for at least one primary axial location along rotor axis A (<FIG>), i.e., where first and second optical targets <NUM>, <NUM> are both present (three shown in example in <FIG>). As observed in <FIG>, lower HJ flange <NUM> can change over an axial length thereof. For example, at different axial locations of lower HJ flange <NUM> (and upper HJ flange <NUM>), it can have different, for example: shape, radial position relative to turbine rotor axis A, radial thickness, and/or structure therein (e.g., cooling channels (see e.g., <FIG>)) extending therethrough. Processing according to embodiments of the disclosure can be carried out at different axial locations to provide highly customized adjustments for component support positions <NUM> at each axial location. In addition, since different sides of lower and upper casings <NUM>, <NUM> can be differently situated even if evaluated at the same axial location, processes P10-P34 can be carried out at one or both sides <NUM>, 110R (<FIG>) of turbine casing <NUM> (<FIG>) at each axial location. While one primary axial location can be used, it is typically advantageous to use a plurality of primary axial locations to obtain better improvement in overall alignment.

Referring to <FIG> and <FIG>, processes P10 and P12 are performed with lower and upper casings <NUM>, <NUM> in a top-on position, as shown in <FIG>. That is, upper casing <NUM> is coupled to lower casing <NUM> in a top-on position. In process P10, as shown in <FIG>, measurement system <NUM> measures a first location L1 of first reference point RP1 at first optical target <NUM>. As noted, first optical target <NUM> is coupled to outer surface <NUM> of lower HJ flange <NUM>. Measurement system <NUM>, as noted, may include any appropriate measurement system for measuring locations of reference points on casings <NUM>, <NUM>, e.g., using lasers. As noted, locations may be indicated by any now known or later developed three dimensional coordinate system.

In process P12, as shown in <FIG>, measurement system <NUM> measures a second location L2 of a second reference point RP2 at a second optical target <NUM> coupled to outer surface <NUM> (<FIG>) of lower HJ flange <NUM> and vertically spaced from first optical target <NUM> (<FIG>). As noted, distance D1 between first and second reference points RP1, RP2 is defined, i.e., known. With processes P10 and P12, alignment system <NUM> may receive locations L1, L2 of reference points RP1, RP2 at measurement module <NUM> for use by calculation module <NUM> to calculate the prediction offset value. Note, optional process P24 occurring in a top-on position will be described further herein.

In process P14, and as shown in <FIG>, upper casing <NUM> is removed from lower casing <NUM>. This operation can be completed using any now known or later developed casing removal process including, for example, removing any insulation, piping, casing fasteners, etc., and lifting upper casing <NUM> off of lower casing <NUM>. Upper casing <NUM> can be set aside for separate evaluation, as will be described herein. While not necessary, other parts that are internal to turbine casing <NUM> (<FIG>) may also be removed such as but not limited to: remaining portions of upper casing <NUM>, turbine rotor <NUM> (<FIG>), a lower portion of diaphragm <NUM> (lower diaphragm), and/or lower casing <NUM> portions. As shown in <FIG>, process P12 and P14 (and P24) may repeat for each primary (or secondary) axial location desired, e.g., three primary axial locations are shown in <FIG> and <FIG>, and over <NUM> secondary axial locations are shown in <FIG>.

Processes P16-P22, and optional steps P26-P30, are performed with lower and upper casings <NUM>, <NUM> in a top-off position, as shown in <FIG>. As shown in <FIG>, with upper casing <NUM> removed, lower casing <NUM>, and in particular, lower HJ flange <NUM> thereof, may shift position, e.g., spring upward, rotate about rotor axis A, tilt inwardly or outwardly, etc. <FIG> shows only one possible scenario which matches <FIG> but includes rotation; however, lower casing <NUM> may take any position described in <FIG>. It is understood that the processing may be applied to any scenario.

In process P16, with at least upper casing <NUM> removed from lower casing <NUM> in a top-off position, measurement system <NUM> measures a third location L3 of first reference point RP1 at first optical target <NUM>. Further, in process P18, with at least upper casing <NUM> removed from lower casing <NUM> in a top-off position, measurement system <NUM> measures a fourth location L4 of second reference point RP2 at second optical target <NUM>. The shift in position of lower casing <NUM> can be observed by comparing third and fourth locations L3, L4 to first and second locations L1, L2 (<FIG>, and shown in phantom in <FIG>). In the <FIG> example, lower HJ flange <NUM> has moved vertically upward and tilt inwardly (counterclockwise) from the position shown in <FIG>. Lower HJ flange <NUM> may have also rotated, e.g., counterclockwise, about rotor axis A.

In process P20, with at least upper casing <NUM> removed from lower casing <NUM> in a top-off position, measurement system <NUM> measures a fifth location of third reference point RP3 on upper surface <NUM> of lower HJ flange <NUM>. As noted, third reference point RP3 has a known spatial relation to component support position <NUM> of component <NUM> in lower casing <NUM>.

In process P22, with at least upper casing <NUM> removed from lower casing <NUM> in a top-off position, measurement system <NUM> measures a sixth location of fourth reference point RP4 on upper surface <NUM> of lower HJ flange <NUM> of lower casing <NUM>. As noted, fourth reference point RP4 is spaced from third reference point RP3 on upper surface <NUM> of lower HJ flange <NUM> by a distance D1. After processes P16-P22, alignment system <NUM> receives locations L3, L4, L5 and L6 of reference points RP1, RP2, RP3, RP4, respectively, at measurement module <NUM> (<FIG>) for use by calculation module <NUM> (<FIG>) to calculate the prediction offset value. As shown in <FIG>, triangular spatial relationship <NUM> of reference points RP1, RP3 and RP4 can be measured, i.e., verifying actual spacing and angular relationships thereof, at each axial location.

With reference to <FIG> and <FIG>, processes P24-P30 are optional measurement steps for secondary axial locations. In process P24, in a top-on position shown partially in <FIG>, measurement system <NUM> measures a seventh location L7 of a seventh optical target RP7 at a first optical target <NUM> at secondary axial location (just RP7 at seventh location L7 of lower casing <NUM> shown in top-on position in <FIG>). Seventh reference point RP7 is substantially identical in function to first reference point RP1, except it is for a secondary axial location. That is, first optical target <NUM> is located at a different axial location than first optical target <NUM> in <FIG>. In process P26, in a top-off position, shown in <FIG>, measurement system <NUM> measures an eighth location L8 of seventh reference point RP7 at first optical target <NUM> at the secondary axial location. In process P28, in a top-off position, measurement system <NUM> measures a ninth location L9 of an eighth reference point RP8 on upper surface <NUM> of lower HJ flange <NUM>. Eighth reference point RP8 is substantially identical in function to third reference point RP3, except it is for a secondary axial location. Hence, eighth reference point RP8 has a known spatial relation to the component support position <NUM> of component <NUM> (<FIG>) in lower casing <NUM> at the respective secondary axial location. In process P28, in a top-off position, measurement system <NUM> measures, a tenth location L10 of a ninth reference point RP9 on upper surface <NUM> of lower HJ flange <NUM>. Ninth reference point RP9 is substantially identical in function to fourth reference point RP4, except it is for a secondary axial location. Hence, ninth reference point RP9 is spaced from eighth reference point RP8 on upper surface <NUM> of lower HJ flange <NUM>.

Top-off position measurement processes (P16-P30) may repeat for any desired number of primary and/or secondary axial locations. Measurement module <NUM> (<FIG>) may receive all of the measured locations L <NUM>-L <NUM>.

In process P32, calculation module <NUM> (<FIG>) calculates the prediction offset value for component support position <NUM> in the top-on position based on first, second, third, fourth, fifth and sixth locations L1-L6 and inner radius (IR) of lower casing <NUM> for at least one of the primary axial locations. In addition, calculation module <NUM> (<FIG>) may also calculate the prediction offset value for component support position <NUM> in the top-on position based on seventh, eighth, ninth and tenth locations L7-L <NUM> and inner radius (IR) of lower casing <NUM> for at least one of the secondary axial location(s). It is also noted that calculation of the prediction offset value for component support position <NUM> in the top-on position for a first side of the turbine casing <NUM> includes accounting for the prediction offset value for the component support position <NUM> in the top-on position for a second, opposite side of the turbine casing. That is, the calculation balances the prediction offset value for each side to ensure changes to one side do not negatively impact or disturb changes to the other side, e.g., rotational adjustments that counteract one another.

Process P32 can take a variety of forms that can be performed individually, or together, in any combination. Consequently, the prediction offset value can take a variety of forms.

In process P34, the method includes a user adjusting component support position <NUM> in turbine casing <NUM> (<FIG>) by the prediction offset value. The adjusting changes component support position <NUM> position to improve an alignment of component <NUM> (<FIG>) with rotor axis A upon replacing upper casing <NUM> of turbine casing <NUM> (<FIG>) to the top-on position. The adjusting may include, for example, as shown in <FIG>, a change in a height (H) of component support position <NUM>, e.g., by changing shim <NUM> and/or ledge <NUM>. In any event, an alignment of component <NUM> (<FIG>) positioned at component support position <NUM> is improved relative to rotor axis A upon replacing upper casing <NUM> to the top-on position (<FIG>). Process P34 can take a variety of forms that can be performed individually, or together, in any combination, e.g., depending on the prediction offset value form.

The following sections will further describe the types of prediction offset value(s) that can be calculated by calculation module <NUM> (<FIG>) in process P32, and the related adjustment(s) that can be performed based on the prediction offset value(s) in process P34.

In certain embodiments, prediction offset value may include a vertical adjustment. In a simplified form, as shown in <FIG>, vertical adjustments can be determined directly from a vertical change in first location L1 and third location L3 of first reference point RP1, i.e., between the top-on position and the top-off position.

As described previously, and as shown in detail in <FIG>, third reference point RP3 and fourth reference point RP4 on upper surface <NUM> of lower HJ flange <NUM>, and first reference point RP1 at first optical target <NUM>, define triangular spatial relationship <NUM> (shaded triangle). More specifically, triangular spatial relationship <NUM> represents the location of reference points RP1, RP3 and RP4 on lower HJ flange <NUM> as they are expected to exist. Triangular spatial relationship <NUM> thus provides a baseline through which changes in lower HJ flange <NUM> can be detected. Triangular spatial relationship <NUM> can be identified, for example, based on initial designs and/or manufacturing records of lower HJ flange <NUM>, or based on previous manufacturing records of changes to lower HJ flange <NUM>. However, triangular spatial relationship <NUM> may also be identified (or verified) by calculation module <NUM> (<FIG>) based on the measured locations of reference points RP1, RP3, RP4 on lower HJ flange <NUM> in the top-off position in process P16, P20 and P22. As shown in <FIG>, calculation module <NUM> also determines a rotation angle (α) of lower HJ flange <NUM> about rotor axis A by calculating an angle between a first vector V1 extending from rotor axis A to first location L1 of first optical target <NUM> in top-on position and a second vector V2 from rotor axis A through third location L3 of first optical target <NUM> in the top-off position.

As shown in <FIG>, calculation module <NUM> can translate triangular spatial relationship <NUM> to the top-on position based on first reference point RP1 at first location L1 in the top-on position and rotation angle (α) of lower HJ flange <NUM> about rotor axis A. That is, it rotates the triangular spatial relationship by rotation angle (α). The translating creates a predicted top-on location LP for third reference point RP3 in the top-on position. In other words, calculation module <NUM> virtually places triangular spatial relationship <NUM> in the top-on position, using first reference point RP1 as the starting point. As shown in <FIG>, triangular spatial relationship <NUM> may be moved vertically and/or rotated to match the rotation angle (α) of lower HJ flange <NUM> in the top-on position. In this setting, predicted top-on location LP of third reference point RP3 indicates where vertically third reference point RP3 should be if there is no distortion in lower HJ flange <NUM>. Calculation module <NUM> calculates any vertical difference (Δz1) between (actual) fifth location L5 of third reference point RP3 as measured and predicted top-on location LP for third reference point RP3 from expected triangular spatial relationship <NUM>. Any vertical difference (Δz1) indicates a vertical change (<FIG> and <FIG>) in the location of third reference point RP3 caused, for example, by distortion in lower HJ flange <NUM> from use. Calculation module <NUM> (<FIG>) calculates a vertical adjustment based on any vertical difference (Δz1) of lower HJ flange <NUM>.

Process P34 may include adjusting component support position <NUM> to one of raise or lower (H) the component support position <NUM> based on the vertical adjustment and the known spatial relation of third reference point RP3 to component support position <NUM> of component <NUM> in lower casing <NUM>. For example, if predicted top-on position LP is <NUM> millimeter higher than the actual, fifth location L5 of third reference point RP3, then component support position <NUM>, e.g., ledge <NUM> and/or shim <NUM>, can be lowered in the tops off condition to accommodate the distortion in lower HJ flange <NUM> so that it is in the correct location when the tops is on and bolted.

In other embodiments, as also shown in <FIG>, vertical adjustments can also be determined from based on a tilt angle (β) of lower HJ flange <NUM>, i.e., between the top-on position and the top-off position. That is, tilt angle (β) of lower HJ flange <NUM> also indicates a vertical change of third reference point RP3 between the top-on position and the top-off position. Here, calculation module <NUM> (<FIG>) calculates the prediction offset value by, as shown in <FIG>, determining a tilt angle (β) of lower HJ flange <NUM> by calculating an angle between a first reference line (FRL) extending through first and second locations L1, L2 (shown in phantom in <FIG>, and solid line in <FIG>) of first and second optical targets <NUM>, <NUM> in top-on position (<FIG>), and a second reference line (SRL) extending through third and fourth locations L3, L4 of first and second optical targets <NUM>, <NUM> in the top-off position (<FIG>). Tilt angle (β) captures any inward or outward tilting of lower HJ flange <NUM> that changes its radial distance from rotor axis A, and a vertical position of component support position <NUM>. In the scenarios of <FIG> and <FIG>, <FIG>, lower HJ flange <NUM> tilts counterclockwise to the top-off position. In <FIG>, <FIG> scenarios, lower HJ flange <NUM> tilts clockwise to the top-off position.

Here, as shown in <FIG>, calculation module <NUM> also calculates any additional vertical difference (Δz2) between (actual) fifth location L5 of third reference point RP3 as measured and predicted top-on location LP for third reference point RP3 from tilt angle (β) of lower HJ flange <NUM>. Note, vertical difference (Δz2) is shown in an exaggerated size for purposes of clarity of illustration, e.g., Δz1 may not be smaller than Δz2. Tilt angle (β) of lower HJ flange <NUM> may be translated to, for example, reference point RP4 and a vertical difference at third reference point RP3 evaluated to identify a change in position of third reference point RP3 caused by tilting of lower HJ flange <NUM>. Any vertical difference (Δz2) indicates an additional vertical change (<FIG>) in the location of third reference point RP3 caused, for example, by distortion in lower HJ flange <NUM> from use. Calculation module <NUM> (<FIG>) calculates a vertical adjustment based on any vertical difference (Δz1) and tilt angle (β), i.e., any vertical difference (Δz2), of lower HJ flange <NUM>.

Process P34, as noted previously, may include adjusting component support position <NUM> to one of raise or lower (H) component support position <NUM> based on the vertical adjustment and the known spatial relation of third reference point RP3 to component support position <NUM> of component <NUM> in lower casing <NUM>. For example, if predicted top-on position LP is a determined to be an additional <NUM> millimeters off due to tilting (i.e., collectively <NUM> millimeter higher than the actual, fifth location L5 of third reference point RP3), then component support position <NUM>, e.g., ledge <NUM> and/or shim <NUM>, can be lowered in the tops off condition to accommodate the distortion in lower HJ flange <NUM> so that it is in the correct location when the tops is on and bolted.

Referring to <FIG>, calculation module <NUM> calculate a first horizontal difference (Δy1) between first location L1 of first optical target <NUM> in the top-on position (dashed lines) and third location L3 of first optical target <NUM> in top-off position (solid lines) at a first side of lower casing <NUM>, and a second horizontal difference (Δy2) between first location L1 of first optical target <NUM> in top-on position (dashed lines) and third location L3 of first optical target <NUM> in top-off position (sold lines) at a second side of lower casing <NUM>. Calculation module <NUM> sums first horizontal difference (Δy1) and second horizontal difference (Δy2) to attain a horizontal adjustment. For example, if first horizontal difference (Δy1) is <NUM> units, and second horizontal difference (Δy2) is -<NUM> units, the sum and horizontal adjustment would be <NUM> units.

In process P34, the adjusting would include adjusting component support position <NUM> based on the horizontal adjustment and the known spatial relation of third reference point RP3 (<FIG>) to component support position <NUM> (<FIG>) of component <NUM> in lower casing <NUM>.

Referring to <FIG>, <FIG> and <FIG>, in certain embodiments, the prediction offset value may include a HJ flange <NUM>, <NUM> surface distortion adjustment to component support position <NUM>. <FIG> shows a schematic cross-sectional view of lower HJ flange <NUM> and upper HJ flange <NUM> in a top-off position with axis on the right. It is noted that while upper casing <NUM> is shown elevated above lower casing <NUM>, it may actually be laying in any orientation off of lower casing, e.g., in a support remote from lower casing <NUM>, flipped over on a floor, etc. As illustrated, with upper casing <NUM> in position to be mounted to lower casing <NUM> (virtually, with perhaps HJ flange surfaces beginning to touch), a gap G may exist, in the example shown, between third reference point RP3 and fifth reference point RP5. Gap G represents an opening that would remain when lower casing <NUM> and upper casing <NUM> are moved to the top-on position caused by HJ flange surface distortion and in existence prior to closing the gap as upper casing <NUM> is fastened to lower casing <NUM>. As illustrated in the example of <FIG>, if lower casing <NUM> and upper casing <NUM> are moved to the top-on position, inner edges <NUM> would meet before outer edges <NUM> of HJ flanges <NUM>, <NUM>, creating a gap G at an outer location near third reference point RP3 and fifth reference point RP5. Note, gap G is shown in an exaggerated size in the drawings for purposes of clarity of illustration. Gap G disappears as casings <NUM>, <NUM> are fastened together. It can be observed in <FIG> that gap G is at least partially correlated to tilt angle (β), such that a prediction offset value to address gap G can be based, in part, on tilt angle (β). In one non-limiting example, a prediction offset value to address gap G can be based on half of tilt angle (β), assuming half of tilt angle (β) is absorbed by each HJ flange <NUM>, <NUM> during reconnection of casings <NUM>, <NUM>. In process P32, calculation module <NUM> can calculate the prediction offset value for component support position <NUM> in the top-on position based on at least the first, second, third, fourth, fifth and sixth locations L1-L6 of lower casing <NUM> and any gap G. In one example, calculation module <NUM> can calculate the prediction offset value to include a HJ flange surface distortion adjustment at third reference point RP3 to accommodate half of tilt angle (β) to address gap G. It is appreciated that gap G could also be between fourth and sixth reference points RP4, RP6 if HJ flanges <NUM>, <NUM> tilt in an opposite direction. It is also appreciated that no gap G may exist where HJ flanges <NUM>, <NUM> remain parallel to one another.

In process P34, component support position <NUM> (see e.g., <FIG>) may be adjusted in turbine casing <NUM> (<FIG>) by the prediction offset value including the HJ flange surface distortion adjustment.

In an optional embodiment, in order to confirm the presence and/or extent of gap G, in certain embodiments, as shown in <FIG>, calculation module <NUM> can also calculate any gap G at an inner location near third reference point RP3 and fifth reference point RP5, or an outer location near fourth reference point RP4 and sixth reference point RP6 based on an angular relationship between a first reference line RL1 and a second reference line RL2 and the inner radius IR of lower casing <NUM>. Again, gap G represents an opening that would remain when lower casing <NUM> and upper casing <NUM> are moved to the top-on position caused by HJ flange surface distortion and in existence prior to closing the gap as upper casing <NUM> is fastened to lower casing <NUM>. As illustrated in the example of <FIG>, if lower casing <NUM> and upper casing <NUM> are moved to the top-on position, inner edges <NUM> would meet before outer edges <NUM> of HJ flanges, creating a gap at an outer location near third reference point RP3 and fifth reference point RP5.

As shown in <FIG>, in process P32, calculation module <NUM> identifies a first reference line RL1 through third reference point RP3 and fourth reference point RP4 on lower HJ flange <NUM> in a top-off position. Further, in process P32, calculation module <NUM> identifies a second reference line RL2 through a fifth reference point and a sixth reference point of a lower (as shown) surface <NUM> of upper HJ flange <NUM>. As illustrated, rotor axis A is known for lower casing <NUM>, and a rotor axis A' is (virtually) known for upper casing <NUM>, e.g., the latter based on its shape, inner radius and perhaps other dimensions. As shown in <FIG>, calculation module <NUM> establishes an angular relationship between first reference line RL1 and second reference line RL2 by superimposing rotor axis A' of upper HJ flange <NUM> in the top-off position with rotor axis A of lower HJ flange <NUM> in the top-off position. Calculation module <NUM> can then calculate (confirm) any gap G at an inner location near third reference point RP3 and fifth reference point RP5, or an outer location near fourth reference point RP4 and sixth reference point RP6 based on the angular relationship between first reference line RL1 and second reference line RL2 and the inner radius IR of lower casing <NUM>. Again, gap G represents an opening that would remain when lower casing <NUM> and upper casing <NUM> are moved to the top-on position caused by HJ flange surface distortion and in existence prior to closing the gap as upper casing <NUM> is fastened to lower casing <NUM>. As illustrated in the example of <FIG>, if lower casing <NUM> and upper casing <NUM> are moved to the top-on position, inner edges <NUM> would meet before outer edges <NUM> of HJ flanges, creating a gap at an outer location near third reference point RP3 and fifth reference point RP5. Gap G can be calculated (confirmed) by, for example, differencing a length of lines IL and line EL, which are both parallel to vertical axis z. IL extends between inner edges <NUM>, and EL extends between outer edges <NUM>. The location of inner and outer edges <NUM>, <NUM> can be (virtually) calculated based on the other reference points locations and inner radius IR. It is recognized, based on the scenarios in <FIG>, a gap may also exist at the inner location. Calculation module <NUM> calculates the prediction offset value for component support position <NUM> in the top-on position based on at least the first, second, third, fourth, fifth and sixth locations L1-L6 of lower casing <NUM> and any gap.

As noted previously, any number of secondary axial locations (<FIG>) may be provided along rotor axis A that are different than each primary axial location. As shown in <FIG>, <FIG> and <FIG>, each secondary axial location includes first optical target <NUM> but no second optical target <NUM>, i.e., they have only first optical target <NUM>. Embodiments of the disclosure for at least one secondary axial location may occur at one or both sides of turbine casing <NUM>. In process P24-P28, measurement system <NUM> measures seventh, eighth, ninth and tenth locations L7-L10, as shown in <FIG> and <FIG>, at a secondary axial location. Measurement module <NUM> (<FIG>) may receive locations L7-L10, and in process P32, calculation module <NUM> (<FIG>) may calculate the prediction offset value for component support position <NUM> in the top-on position based on seventh, eighth, ninth and tenth locations L7-L10 and inner radius IR of lower casing <NUM> for at least one of secondary axial location. Any of the aforementioned prediction offset values for primary axial locations can be calculated for each secondary axial location. Where tilt angle (β) is required for the calculation, the value is unknown for each secondary axial location because no second reference point RP2 and second optical target <NUM> is provided at those axial locations. In this case, the calculation may use the tilt angle (β) value of the nearest primary axial location.

In process P34, component support position <NUM> in turbine casing <NUM> (<FIG>) at secondary axial location(s) may be adjusted by the prediction offset value therefor in a similar fashion as that described relative to the primary axial locations. The alignment of component <NUM> (<FIG>) positioned at component support position <NUM> for secondary axial location(s) is improved relative to rotor axis A upon replacing upper casing <NUM> to the top-on position.

Processing may be completed by replacing any parts removed from lower casing <NUM> and/or upper casing <NUM>, and replacing upper casing <NUM> on lower casing <NUM>, and fastening it back in place per any now known or later developed technique.

Embodiments of the disclosure provide a method and a system for aligning components that does not require numerous removing steps of the upper casing, thus making the process simpler, safer and less time consuming. The method also provides accurate results without direct measurement of component support positions. The method is also highly flexible and can handle unsymmetrical turbine casings. Technical effect is an alignment system capable of providing adjustments for one or more casings of a turbine casing to align components to be supported therein.

The flowchart and block diagrams in the Figures illustrate the architecture, functionality, and operation of possible implementations of systems, methods and computer program products according to various embodiments of the present disclosure.

As discussed herein, various systems and components are described as "receiving" data (e.g., locations, etc.). It is understood that the corresponding data can be obtained using any solution. For example, the corresponding system/component can include measurement system <NUM> or another system capable of generating and/or being used to generate the data, retrieve the data from one or more data stores (e.g., a database), receive the data from another system/component, and/or the like. When the data is not generated by the particular system/component, it is understood that another system/component can be implemented apart from the system/component shown, which generates the data and provides it to the system/component and/or stores the data for access by the system/component.

The foregoing drawings show some of the processing associated according to several embodiments of this disclosure. In this regard, each drawing or block within a flow diagram of the drawings represents a process associated with embodiments of the method described. It should also be noted that in some alternative implementations, the acts noted in the drawings or blocks may occur out of the order noted in the figure or, for example, may in fact be executed substantially concurrently or in the reverse order, depending upon the act involved. Also, one of ordinary skill in the art will recognize that additional blocks that describe the processing may be added.

Accordingly, a value modified by a term or terms, such as "about," "approximately" and "substantially," are not to be limited to the precise value specified. "Approximately" as applied to a particular value of a range applies to both values, and unless otherwise dependent on the precision of the instrument measuring the value, may indicate +/- <NUM>% of the stated value(s).

Claim 1:
A method of aligning a component (<NUM>) within a turbine casing, the turbine casing (<NUM>) including an upper casing (<NUM>) and a lower casing (<NUM>) configured to collectively surround a rotor (<NUM>), the rotor (<NUM>) having a rotor axis (A), the method comprising:
for at least one primary axial location along the rotor axis (A) and at one or both sides of the turbine casing (<NUM>) at each primary axial location:
with the upper casing (<NUM>) coupled to the lower casing (<NUM>) in a top-on position, measuring:
a first location (L1) of a first reference point (RP1) at a first optical target (<NUM>) coupled to an outer surface (<NUM>) of a horizontal joint (HJ) flange (<NUM>) of the lower casing (<NUM>), and
a second location (L2) of a second reference point (RP2) at a second optical target (<NUM>) coupled to the outer surface (<NUM>) of the HJ flange (<NUM>) of the lower casing (<NUM>) and vertically spaced from the first optical target (<NUM>);
with at least the upper casing (<NUM>) removed from the lower casing (<NUM>) in a top-off position, measuring:
a third location (L3) of the first reference point (RP1) at the first optical target (<NUM>),
a fourth location (L4) of the second reference point (RP2) at the second optical target (<NUM>),
a fifth location (L5) of a third reference point (RP3) on an upper surface (<NUM>) of the horizontal joint (HJ) flange (<NUM>) of the lower casing (<NUM>), the third reference point (RP3) having a known spatial relation to a component support position (<NUM>) of the component (<NUM>) in the lower casing (<NUM>) at the respective primary axial location, and
a sixth location (L6) of a fourth reference point (RP4) on the upper surface (<NUM>) of the HJ flange (<NUM>) of the lower casing (<NUM>), the fourth reference point (RP4) spaced from the third reference point (RP3) on the upper surface (<NUM>) of the HJ flange (<NUM>) of the lower casing (<NUM>);
calculating a prediction offset value for the component support position (<NUM>) in the top-on position based on at least the first, second, third, fourth, fifth and sixth locations (L1-L6) and an inner radius (IR) of the lower casing (<NUM>); and
adjusting the component support position (<NUM>) in the turbine casing (<NUM>) by the prediction offset value, wherein an alignment of the component (<NUM>) positioned at the component support position (<NUM>) is improved relative to the rotor axis (A) upon replacing the upper casing (<NUM>) to the top-on position.