Abstract:
A cutting element includes, a gilmoid with a plurality of cutting edges thereon, and at least one support extending from the gilmoid, the at least one support and at least one of the plurality of cutting edges are simultaneously contactable with a surface upon which the cutting element is restable.

Description:
BACKGROUND 
       [0001]    Cutting tools, such as mills used in downhole applications, for example, can be made with a plurality of cutting elements that are adhered to a surface of a tool. The cutting elements can be randomly shaped particles made by fracturing larger pieces. Alternately, cutting elements can be precisely formed into repeatable shapes using processes such as machining and molding, for example. Regardless of the process employed to make the individual cutting elements the elements are typically adhered to the mill with random orientations. These random orientations create disparities in maximum heights relative to a surface of the mill Additionally, large disparities may exist between the heights of the portions of the cutting elements that engage the target material during a cutting operation. Furthermore, angles of cutting surfaces relative to the target material are randomized and consequently few are near preferred angles that facilitate efficient cutting. Apparatuses and methods to lessen the foregoing drawbacks would therefore be well received in the industry. 
       BRIEF DESCRIPTION 
       [0002]    Disclosed herein is a cutting element. The cutting element includes, a gilmoid with a plurality of cutting edges thereon, and at least one support extending from the gilmoid, the at least one support and at least one of the plurality of cutting edges are simultaneously contactable with a surface upon which the cutting element is restable. 
         [0003]    Further disclosed herein is a method of orienting a cutting element. The method includes, configuring the cutting element so that gravitational forces acting thereon against a surface bias the cutting element to an orientation relative to the surface in which at least one support and at least one side of a polygon of a gilmoid contact the surface. 
         [0004]    Further disclosed herein is a cutting element. The cutting element includes, a body having a portion configured as a polygonal prism that is longitudinally asymmetrically weighted with respect to the portion, a plurality of cutting edges defined at intersections of surfaces of the polygonal prism, and at least one support extending longitudinally beyond the portion. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0005]    The following descriptions should not be considered limiting in any way. With reference to the accompanying drawings, like elements are numbered alike: 
           [0006]      FIG. 1  depicts a side view of a cutting element disclosed herein; 
           [0007]      FIG. 2  depicts another side view of the cutting element of  FIG. 1 , shown resting at an alternate orientation on a surface; 
           [0008]      FIG. 3  depicts a perspective view of the cutting element of  FIGS. 1 and 2 , shown resting at the orientation of  FIG. 2 ; 
           [0009]      FIG. 4  depicts a perspective view of an alternate embodiment of a cutting element disclosed herein; 
           [0010]      FIG. 5  depicts a perspective view of a central portion of the cutting element; and 
           [0011]      FIG. 6  depicts a side view of the central portion of the cutting element of  FIG. 5 . 
       
    
    
     DETAILED DESCRIPTION 
       [0012]    A detailed description of one or more embodiments of the disclosed apparatus and method are presented herein by way of exemplification and not limitation with reference to the Figures. 
         [0013]    Referring to  FIG. 1 , an embodiment of a cutting element disclosed herein is illustrated at  10 . The cutting element  10  includes, a central portion  20  disclosed herein as a gilmoid, as will be described in detail below with reference to  FIGS. 5 and 6 , defining a plurality of cutting edges  16 A,  16 B, and two supports  24 A and  24 B that extend beyond surfaces  32 A and  32 B that define certain volumetric boundaries of the gilmoid  20 . In this embodiment the supports  24 A and  24 B are not symmetrical to one another to produce a biasing force in response to gravity acting thereon toward a surface  38 , such that one of the supports  24 A,  24 B and one of the cutting edges  16 A,  16 B are in contact with surface  38 . 
         [0014]    Referring to  FIGS. 2 and 3 , the biasing forces tend to cause the cutting element  10  to reorient from the position illustrated in  FIG. 1  to the position illustrated in  FIGS. 2 and 3 . The cutting element  10 , as illustrated in  FIGS. 2 and 3 , is resting on the surface  38  such that both the support  24 B and one of the cutting edges  16 B is in contact with the surface  38 . The cutting edges  16 A, in this position, are oriented with the surface  32 A at an approximately 45 degree (and preferably between 35 and 55 degrees) angle relative to the surface  38 , and represent a preferred cutting orientation that can cut with greater efficiency than alternate angles. In contrast, the cutting element  10  in  FIG. 1  is positioned such that just one face  42 , defined between the two cutting edges  16 A and  16 B, is in contact with the surface  38 . In this position a longitudinal axes of the gilmoid  20  is substantially parallel with the surface  38 . Additionally, although axes  40 A,  40 B of the supports  24 A,  24 B are illustrated herein with an angle of 180 degrees between them, angles of 120 degrees or more are contemplated. 
         [0015]    The cutting element  10  is further geometrically configured so that when the cutting element  10  is resting on the surface  38 , regardless of its orientation, a dimension  46  to a point on the cutting element  10  furthest from the surface  38  is substantially constant. This assures a relatively even distribution of cutting forces over a plurality of the cutting elements  10  adhered to the surface  38 . 
         [0016]    The foregoing structure allows a plurality of the cutting elements  10  to be preferentially oriented on the surface  38  prior to being fixedly adhered to the surface  38 . While orientations of each of the cutting elements  10  is random in relation to a direction of cutting motion the biasing discussed above orients a majority of the cutting elements  10  as shown in  FIGS. 2 and 3  relative to the surface  38 . Having a majority of the cutting elements  10  oriented as shown in  FIGS. 2 and 3  improves the cutting characteristics of a cutter employing these cutting elements  10  over cutters employing non-biasing cutting elements. 
         [0017]    The supports  24 A and  24 B illustrated herein are geometrically asymmetrical, as is made obvious by the difference in widths  50 A and  50 B of the supports  24 A and  24 B, respectively. This asymmetry creates the asymmetrical bias discussed above in response to gravitational forces acting on the cutting element  10  in a direction parallel to the surfaces  32 A,  32 B. Alternate embodiments are contemplated that have supports that are geometrically symmetrical while providing the asymmetrical bias with gravity. A difference in density between such supports is one way to create such an asymmetrical gravitational bias with geometrically symmetrical supports. 
         [0018]    A width  54  of the central portion  20 , defined between the planes  28 A and  28 B, can be set large enough to provide strength sufficient to resist fracture during cutting while being small enough to allow the gravitational asymmetrical bias on the cutting element  10  to readily reorient the cutting element  10  relative to the surface  38  and be effective as a cutting element. 
         [0019]    Additionally in this embodiment, by making a base dimension  55 , defined as where the supports  24 A,  24 B interest with the surfaces  32 A,  32 B, smaller than the dimension  46 , a right angled intersection is defined at the cutting edges  16 A,  16 B. A distance  56  between an intersection  57  of the supports  24 A,  24 B with the surfaces  32 A,  32 B and the faces  42 ,  58 ,  62  provides a space where the material being cut can flow and can create a barrier to continued propagation of a crack formed in one of the cutting edges  16 A,  16 B beyond the intersections  57 . Preferably, the base dimension  55  is sized to be between 40 and 80 percent of the dimension  46  and more preferably about 60 percent. 
         [0020]    Referring to  FIG. 3 , additional faces  58  defined between the cutting edges  16 A and  16 B can be incorporated as well. In fact, any number of faces  42 ,  58  can be provided between the cutting edges  16 A and  16 B thereby forming a polygonal prism of the central portion  20 , including just four faces  62  as illustrated in  FIG. 4  in an alternate embodiment of a cutting element  110  disclosed herein. 
         [0021]    The cutting elements  10 ,  110  disclosed herein may be made of hard materials that are well suited to cutting a variety of materials including, for example, those commonly found in a downhole wellbore environment such as stone, earth and metal. These hard materials, among others, include steel, tungsten carbide, tungsten carbide matrix, polycrystalline diamond, ceramics and combinations thereof. 
         [0022]    Although the embodiments discussed above are directed to a central portion  20  that is a polygonal prism, alternate embodiments can incorporate a central portion  20  that has fewer constraints than is required of a polygonal prism. As such, the term gilmoid has been introduced to define the requirements of the central portion  20 . Referring to  FIGS. 5 and 6 , the gilmoid  20  is illustrated without supports  24 A,  24 B shown. The gilmoid  20  is defined by two polygons  70 A,  70 B with surfaces  74  that connect sides  78 A of the polygon  70 A to sides  78 B of the other polygon  70 B. The two polygons  70 A,  70 B can have a different number of sides  78 A,  78 B from one another, and can have a different area from one another. Additionally, planes  82 A,  82 B, in which the two polygons  70 A,  70 B exist, can be parallel to one another or can be nonparallel to one another, as illustrated. 
         [0023]    While the invention has been described with reference to an exemplary embodiment or embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the claims Also, in the drawings and the description, there have been disclosed exemplary embodiments of the invention and, although specific terms may have been employed, they are unless otherwise stated used in a generic and descriptive sense only and not for purposes of limitation, the scope of the invention therefore not being so limited. Moreover, the use of the terms first, second, etc. do not denote any order or importance, but rather the terms first, second, etc. are used to distinguish one element from another. Furthermore, the use of the terms a, an, etc. do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced item.