Patent Application
20140137712
The disclosure relates generally to machining, and more particularly to lathe centers used in the manufacture and/or assembly of rotating machinery, such as turbine rotors.
A rotor assembly can include a number of cylindrical and/or conical and/or annular parts that are typically formed by machining with a lathe or the like. During machining, such parts are generally secured using lathe centers, which are typically formed in weld cavities in the ends of parts being machined. Once the parts are machined, they can be welded together to form a rotor assembly, leaving a weld cavity in the assembly including a weld cavity from each welded part. Typically, each lathe center is formed in a vertical wall of the weld cavity, but this can introduce stress and/or strain in the assembly during operation and/or startup.
Embodiments of the invention disclosed herein may take the form of a lathe center in which a boss can project from an end wall of a cavity in a work end of a work piece. At least one support recess can be formed in the boss, and a boss height of the boss as measured from the end wall can be at least equal to a depth of a deepest support recess.
Another embodiment may include a lathe center that can include a cavity formed in a work end of a work piece. A boss can project from an end wall at a deepest portion of the cavity. At least one support recess in the boss can penetrate into the boss, none of the at least one support recess penetrating further than the end wall.
A further embodiment can include a work piece, a work end of the work piece, and a substantially cylindrical cavity in the work end. The cavity can have an end wall, and a substantially cylindrical boss can project from the end wall into the cavity. The boss can be made from a material, and a height of the boss can be based on at least one of a property of the material or an expected load to be applied to the lathe center. In addition, at least one support recess can be formed in the boss with a respective support recess depth. A deepest support recess of the at least one support recess can have a respective support recess depth no greater than the boss height.
Other aspects of the invention provide methods of making embodiments of the invention disclosed herein, as well as variants of the apparatus, which include and/or implement some or all of the actions and/or features described herein. The illustrative aspects of the invention are designed to solve one or more of the problems herein described and/or one or more other problems not discussed.
These and other features of the 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 aspects of the invention.
It is noted that the drawings may not be to scale. The drawings are intended to depict only typical aspects of the invention, and therefore should not be considered as limiting the scope of the invention. In the drawings, like numbering represents like elements between the drawings.
The detailed description explains embodiments of the invention, together with advantages and features, by way of example with reference to the drawings.
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Additional stress and/or strain reductions can be achieved by limiting a support recess width 117 of a widest support recess of support recess(es) 112 relative to a boss width 118. The particular limitation on support recess width 117 in embodiments can be determined based on an expected load to be applied to lathe center 100, a material property of material used to make lathe center 100, boss 110, work piece 10, and/or lathe work tips (not shown) to be used with lathe center 100, and/or any other factors as may be suitable and/or appropriate. In embodiments, support recess width 117 can be limited to no more than a determined percentage of boss width 118 as may be appropriate and/or desired. Where boss 110 and/or support recess(es) 112 have substantially circular cross sections as taken transverse to an axis of rotation of work piece 10, the respective widths 117, 118 are respective diameters of boss 110 and/or support recess(es) 112. It should be noted that the percentages used as examples in this description are not limiting, and that any percentages can be used as may be appropriate and/or desired. In addition, it should be recognized that lathe center 100 need not be limited in use to only shafts and/or only work pieces that are to be welded together. Rather, lathe center 100 can be employed in any work piece that would be machined in a lathe or the like.
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.
