Patent Application
20140237820
The invention relates to apparatus and methods for installing a turbine blade in a turbine rotor by supported and guided insertion of the turbine blade root into a corresponding rotor slot.
A turbine blade is inserted into a rotor by concentrically aligning and slidably inserting a male blade root within a tightly conforming corresponding female slot in the rotor while the rotor is suspended in a fixture. Given the physical weight and length of a rotor blade, it is challenging to align corresponding blade root and rotor slot structures with sufficient precision to slide the blade into its inserted position within the rotor.
Past known insertion methods and tools have included manual blade manipulation by human operators using portable hand dollies; robotic blade manipulation arms in factory manufacturing or service facilities rather than field environments; pneumatic table blade lifts and overhead cranes or equivalent manual hoists Each of the known blade insertion methods and tools has disadvantages in manufacturing or service facilities or in field installation sites.
Manual blade manipulation by human operators with wheeled dollies and other non-supported, muscle-manipulated tools is physically exhausting to the operators, as they must physically lift the blade into vertical alignment position with the rotor while simultaneously laterally aligning the blade root and rotor slot. Unsupported manual blade lifting and vertical/lateral alignment manipulation also risks potential blade damage if the blade slips or drops due to mishandling error.
Robotic blade manipulation arms are helpful for constructing or maintaining turbine blades that are removed from a rotor, but their relatively large size and limited range of offset blade manipulation motion that otherwise might risk tipping of robotic tool due to the heavy offset blade load makes them impractical for use as a blade insertion tool.
As with robotic blade manipulation arms, air-powered table-type lifts have relatively large footprints that are more suited for blade installation in manufacturing or service sites but are often too large for practical use in turbine field sites. Vertical position of the pneumatic table changes during blade loading and unloading, which potentially shifts the table's center of gravity. Loading and unloading weight on the pneumatic table also imparts oscillatory motion on the table, making lateral blade root/rotor slot alignment difficult.
Overhead cranes and hoists require insertion of the blades at a 12 o'clock elevated radial position on the suspended rotor, rather than at a 6 o'clock ground-level position, because the suspended rotor lack of vertical clearance interferes with crane or hoist positioning from under the rotor. It is more difficult for human operators to install blades into a rotor from a 12 o'clock elevated position as compared to floor elevation installation.
Some embodiments of a turbine blade insertion tool of the invention facilitate supported vertical and lateral alignment of a turbine blade root and a corresponding rotor slot from under a suspended rotor. The insertion tool includes a vertically supported blade lift fixture that slidably retains the blade root while manually biasable slide that is coupled to the blade fixture provides supported relative vertically adjustable alignment between the blade root and rotor slot. Supported lateral root/slot alignment is provided by manually swinging the blade lift fixture on a three-dimensional motion-capable swivel eye and corresponding lift hook that are both coupled to the manually adjustable vertical slide. Some embodiments of the blade insertion tool of the invention have swivel rollers that facilitate manual maneuvering under the rotor.
Some embodiments of the invention feature a method for inserting a turbine blade root into a corresponding downwardly oriented turbine rotor slot of a vertically suspended rotor. A blade insertion tool is provided, having a man-maneuverable base and a vertical column projecting upwardly from the base having a distal end height adapted for passage under a vertically suspended rotor.
The blade insertion tool has a blade lift fixture defining a cavity for slidable receipt and retention of a blade root therein that is coupled to the distal end of the vertical column by a three-axis degree of freedom joint. The blade insertion tool is used by slidably inserting and retaining a turbine blade root of a turbine blade into the blade lift fixture and raising the blade lift fixture with the turbine blade suspended therefrom. The blade lift fixture is coupled to the vertical column distal end with the joint, thereby vertically suspending and supporting the blade with the blade insertion tool. The blade insertion tool is maneuvered under the suspended rotor and thereafter coaxially aligning the blade root and rotor slot by maneuvering the suspended blade and the blade lift fixture. Once the blade root and rotor slot are aligned the blade root is slidably inserted at least partially into the rotor slot and the blade root is released from the blade lift fixture. Thereafter the blade root continues to be slid into the rotor slot until the blade is in a fully seated position on the rotor.
Other embodiments of the invention feature a blade insertion tool apparatus including a man-maneuverable base and a vertical column projecting upwardly from the base having a distal end height adapted for passage under a vertically suspended rotor. A blade lift fixture defining a cavity for slidable receipt and retention of a blade root therein is selectively coupled to the distal end of the vertical column by a three-axis degree of freedom joint. Some embodiments of the apparatus include one or more of the three degree of freedom joint having a lift hook and a swivel eye; and/or a biasing mechanism having threaded screws projecting into the blade lift fixture cavity, for pinch restrain the turbine blade root when biased into abutting contact therewith; and/or the man-maneuverable base having swivel rollers and spring-biased ball casters for maintaining tilt stability of the blade insertion tool during rolling maneuvers over uneven surfaces.
The respective features of embodiments of the present invention may be applied jointly or severally in any combination or sub-combination by those skilled in the art.
The teachings of the present invention can be readily understood by considering the following detailed description in conjunction with the accompanying drawings, in which.
To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures.
After considering the following description, those skilled in the art will clearly realize that the teachings of the present invention can be readily utilized in a turbine blade insertion tool of the invention, embodiments of which facilitate supported vertical and lateral alignment of a turbine blade root and a corresponding rotor slot from under a suspended rotor. The insertion tool includes a vertically supported blade lift fixture that slidably retains the blade root while manually biasable slide that is coupled to the blade fixture provides supported relative vertically adjustable alignment between the blade root and rotor slot. Supported lateral root/slot alignment is provided by manually swinging the blade lift fixture on a three-dimensional motion-capable swivel eye and corresponding lift hook that are both coupled to the manually adjustable vertical slide. Some embodiments of the blade insertion tool of the invention have swivel rollers that facilitate manual maneuvering under the rotor.
A blade insertion tool 20 that is constructed in accordance with an embodiment of the invention slidably retains the rotor root 18 and thus vertically supports the entire rotor blade 16. The embodiment of the blade insertion tool 20 provides for supported manual height adjustment ΔH and supported manual orientation of the tool under the rotor 12, for ground level insertion of the blade at a convenient 6 o'clock radial rotor position. Ground level insertion is more convenient for the blade installers than requiring them to utilize scaffolding or ladders that would be otherwise necessary for insertion of a turbine blade at an elevated 12 o'clock rotor position.
Referring generally to
A vertical support structure column 34, shown as constructed from segments of tubular material, is coupled to the base 22, along with vertically-oriented backing plate 36. Together they vertically support the suspended weight of the turbine blade 16. The support column 34 and vertically-oriented backing plate 36 are affixed to the base 22 in a lateral relative position L1 that is chosen to resist tipping of the blade insertion tool 20 due to the offset retention of the blade 16 weight. The blade weight's tipping moment is resisted by the portion of the base 22 of length L1 while the remaining portion of the base on the opposite side from the suspended blade resists tipping in that direction. A relative ratio of L1: L of 2:3 is satisfactory to inhibit suspended blade tipping of the blade insertion tool 20.
Vertical height adjustment ΔH for the suspended turbine blade 16 is provided by manually-manipulated dovetailed slide 38, which is of known and commercially available structure The dovetailed slide 38 is often constructed with a machine screw and pinion that is manipulated by turning the handle 40, though a motor- or hydraulically-driven power source may be substituted for the manual drive mechanism. A base portion of the slide 38 is coupled to the backing plate 36 while the translatable (driven) portion of the slide is coupled to a slide back plate 42. Lift hook 44, advantageously including but not requiring a snap link toggle as shown, is coupled to the slide back plate 44, such as by welding.
Referring to
A blade protective pad 52, constructed of a resilient material, such as polyurethane foam, is interposed between the lifting body upper interior surface and the blade root Concave depressions formed within the blade root 18 profile receive a plurality of corresponding inwardly directed blade retention projections, which as shown in the embodiments herein are cap screws 54 that are retained within mating threads formed in the blade lifting body Resilient blade protective caps 56 cover male projecting ends of each cap screw 54 to avoid potential blade damage that might otherwise be caused by direct metal-to-metal contact between the screws and the blade root. The cap screws 54 optionally are tightened lightly in contact with the blade root for a “pinch-tight” fit, so that the blade 16 is retained within the blade lift fixture 46 during its transport on the blade insertion tool 20 until co-axial relative alignment is achieved with the rotor slot 14. Grip handle 58 facilitates manual movement of the blade removal tool 20 for achieving blade 16 and rotor 12 relative alignments under the rotor, while optional blade retention straps 60 inhibit suspended blade swinging on the three-dimensional range of motion joint formed between the lift hook 44 and the swivel eye 50. As shown in
Although various embodiments that incorporate the teachings of the present invention have been shown and described in detail herein, those skilled in the art can readily devise many other varied embodiments that still incorporate these teachings The invention is not limited in its application to the exemplary embodiment details of construction and the arrangement of components set forth in the description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways.
Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. Unless specified or limited otherwise, the terms “mounted,” “connected,” “supported,” and “coupled” and variations thereof are used broadly and encompass direct and indirect mountings, connections, supports, and couplings.
Further, “connected” and “coupled” are not restricted to physical or mechanical connections or couplings.
This application claims the benefit of priority of co-pending United States provisional patent application entitled “Turbine Blade Insertion Tool” filed Feb. 28, 2013 and assigned Ser. No. 61/770,706, the entire contents of which is incorporated by reference.
| Number | Date | Country | |
|---|---|---|---|
| 61770706 | Feb 2013 | US |
