Patent Application
20100172755
The subject matter disclosed herein relates to axial compressors. More particularly, the subject relates to the installation of stator vanes in an axial compressor.
An axial compressor consists of both rotating and stationary components. A shaft drives a central drum, which has a number of annular rotors. Rotor sections rotate between a similar number of stationary stator sections, each stator section attached to a stationary outer tube case. Each of the sections of rotors and stators include a plurality of vanes around which airflow passes. Compressors often utilize complex non-uniform vane schemes or other asymmetric vane arrangements for various reasons both within each section, and between different sections. Non-uniform vane schemes utilize differently shaped vanes in addition to differently angled vanes. In the case of each stator vane section, these non-uniform schemes must be assembled in specific circumferential locations along the compressor case section in order to have the desired effect. The art would therefore be receptive to a method and apparatus for insuring the proper installation of stator vanes.
According to one aspect of the invention, a compressor case assembly that includes a compressor case section having an assembly track and a set of stator portions that are insertable in the assembly track, the compressor case section and the set of stator portions are configured such that the set of stator portions only assembles to the compressor case section in a single configuration.
According to another aspect of the invention, a method of insuring proper installation of stator portions to a compressor case includes inserting a set of stator portions into an assembly track of the compressor case, the assembly track and the set of stator portions each are keyed such that each of the stator portions only assemble to the compressor case in a single configuration.
According to yet another aspect of the invention, a method of insuring proper installation of stator portions to a compressor case includes keying an assembly track of the compressor case and keying each of a set of stator portions such that the set of stator portions only assemble to the compressor case in a single configuration.
The subject matter which is regarded as the invention is particularly pointed out and distinctly claimed in the claims at the conclusion of the specification. The foregoing and other features and advantages of the invention are apparent from the following detailed description taken in conjunction with the accompanying drawings in which:
A detailed description of the hereinafter described embodiments of the disclosed apparatus and method are presented herein by way of exemplification and not limitation with reference to the Figures.
Referring to
The compressor case section 11 has an outer surface 20 and an inner surface 22. The assembly track 18 is located along the inner surface 22 and extends the perimetrical length of the compressor case section 10 from a first end 24, to a second end 26. The assembly track 18 is configured to receive the set of stator portions 12, 14, 16. The stator portions 12, 14, 16 may have a square or rectangular shaped base, or any other base that is insertable into the assembly track 18. Each of the stator portions 12, 14, 16 includes at least one stator vane 28, as shown in
The assembly track 18 may be configured to receive the stator portions 12, 14, 16 from either the first end 24 or the second end 26 during assembly. In this embodiment, the stator portions 12, 14, 16 are insertable into the assembly track 16 from the first end 24 in a first assembly direction 30 or from the second end 26 in a second assembly direction 32. In this embodiment, the assembly track 18 also includes two assembly slots 34 to provide space for two corresponding base lips 38 of the stator portions 12, 14, 16 to assist in the assembly and the retention of the stator portions 12, 14, 16 within the assembly track 18. The assembly track 18 and the stator portions 12, 14, 16 may include any other mechanism that insures that the stator portions 12, 14, 16 are held secure within the assembly track 18.
The assembly track 18 is configured to receive each of the stator portions 12, 14, 16 only within a particular assembly circumferential location 42, 44, 46. The assembly circumferential locations 42, 44, 46 for each of the stator portions 12, 14, 16 is individualized so that each individual stator portion 12, 14, 16 has a corresponding individual assembly circumferential location 42, 44, 46. These individualized assembly circumferential locations 42, 44, 46 insure the correct location for the stator vanes 28 that have a deliberate non-uniform scheme. For example, in this embodiment, the first stator portion 12 can only be assembled into the first assembly circumferential location 42, the second stator portion 14 can only be assembled into the second assembly location 44 and the third stator portion 16 can only be assembled into the third stator assembly circumferential location 46.
To insure that the stator portions 12, 14, 16 are assembled into only the correct individualized assembly circumferential locations 42, 44, 46, the assembly track 18 and the stator portions 12, 14, 16 are keyed to one another. Particularly, the assembly track 18 is keyed to include at least one protrusion 48, 50, 52, 54 and at least one of the stator portions 12, 14, 16 is keyed to include at least one stator slot 56, 58, 60. When the stator portions 12, 14, 16 are inserted into the assembly track 18, the stator slots 56, 58, 60 have a parallel alignment with the assembly directions 30, 32 and are also aligned in a horizontal direction 64 with at least one of the protrusions 48, 50, 52, 54. The protrusions 48, 50, 52, 54 may be configured so that the stator portion 12, 14, 16 is insertable in only one parallel alignment and will not be insertable if the stator 12, 14, 16 portion is flipped 180 degrees to another parallel alignment. Further, each of the stator slots 56, 58, 60 is configured to provide clearance for this corresponding protrusion 48, 50, 52, 54 to allow the stator portion 12, 14, 16 to bypass the corresponding protrusion 48, 50, 52, 54 during assembly. In one embodiment, this is achieved because each of the stator slots 56, 58, 60 has a greater depth than the height of the corresponding protrusion 48, 50, 52, 54, and a greater width than the interfering width of the corresponding protrusion 48, 50, 52, 54 in order to provide this clearance. Further, each of the protrusions 48, 50, 52, 54 is located at periodic intervals between the first end 24 and the second end 26. When one of the stator portions 12, 14, 16 does not include a corresponding stator slot 56, 58, 60 for one of the protrusions 48, 50, 52, 54, that protrusion 48, 50, 52, 54 interferes with the insertion of that stator portion 12, 14, 16. Thus, the protrusions 48, 50, 52, 54 are configured to selectively interfere with the insertion of the stator portions 12, 14, 16 into the assembly track 18.
The protrusions 48, 50, 52, 54 may be any of the following: a pin, a screw, a weldment, a bolt, or any other appropriate projection extending into the assembly track 18. The protrusions 48, 50, 52, 54 may also have a profile that is generally circular, polygonal, or any other shape. Further, in an embodiment having a plurality of the protrusions 48, 50, 52, 54, the protrusions 48, 50, 52, 54 may each have a similar height. Alternately, one or more of the protrusions 48, 50, 52, 54 may have a different height than another of the protrusions 48, 50, 52, 54.
Referring by way of example to the embodiment shown in
Referring to
In another embodiment of the present invention, the compressor case slots 66 of the compressor case section 11 have different dimensions from the compressor case slots of another compressor case section (not shown). In this embodiment, the compressor case slots 66 of the compressor case section 11 are configured to only accept the stator elevations 68 of the stator portions 12, 14, 16, and not the stator portions (not shown) having a correct assembly location in another compressor case section. Thus, in this embodiment, the compressor case slots 66 in conjunction with the stator elevations prevent incorrect stage-to-stage assembly of stator portions.
Elements of the embodiments have been introduced with either the articles “a” or “an.” The articles are intended to mean that there are one or more of the elements. The terms “including” and “having” and their derivatives are intended to be inclusive such that there may be additional elements other than the elements listed. The conjunction “or” when used with a list of at least two terms is intended to mean any term or combination of terms. The terms “first” and “second” are used to distinguish elements and are not used to denote a particular order.
While the invention has been described in detail in connection with only a limited number of embodiments, it should be readily understood that the invention is not limited to such disclosed embodiments. Rather, the invention can be modified to incorporate any number of variations, alterations, substitutions or equivalent arrangements not heretofore described, but which are commensurate with the spirit and scope of the invention. Additionally, while various embodiments of the invention have been described, it is to be understood that aspects of the invention may include only some of the described embodiments. Accordingly, the invention is not to be seen as limited by the foregoing description, but is only limited by the scope of the appended claims.
