Patent Application
20150075874
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
Disclosed herein is a method of making a cutting device. The method includes, positioning a first element and a second element on a cutter surface, stacking a third element onto the first element and the second element, the third element has a modified gilmoid with a support protruding from at least one of two plane-defined-surfaces that define the modified gilmoid, such that the one of two plane-defined-surfaces of the modified gilmoid further from the cutter surface forms an angle of between about 35 and 55 degrees with the cutter surface, attaching the third element to the first element and the second element, and attaching the first element and the second element to the cutter surface.
Further disclosed herein is a cutting device. The device includes, at least one stack of cutting elements attached to a cutter surface having, a first element and a second element attached to the cutter surface, and a third element attached to the first element and the second element, the three elements being sized and shaped such that prior to attachment to the cutter surface the three elements are restable in a stable manner on the cutter surface due to gravity alone such that a plane-defined-surface defined by one of the two planes of a modified gilmoid of the third element positioned further from the cutter surface is oriented at an angle of about 35 to 55 degrees relative to the cutter surface.
The following descriptions should not be considered limiting in any way. With reference to the accompanying drawings, like elements are numbered alike:
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.
Referring to
The three cutting elements 110A, 110B, 110C in the embodiment of
Although not required, in the embodiment illustrated all three of the cutting elements 110A, 110B, and 110C have the same shape and the same orientation relative to the cutting device 300. This orientation includes angles 130 between the plane-defined-surface 32B and the cutter surface 38 of all three of the cutting elements 110A, 110B, 110C having the same angle. Additionally, in this embodiment the first element 110A is the same size as the second element 110B while the third element 110C is of a smaller size. This size relationship aids in creating the stable structure of the stack 114 resting on the cutter surface 38 due to gravity alone prior to the elements 110A, 110B, 110C being attached to each other and to the surface 38. Further adding to this stability is aligning the three elements 110A, 110B, 110C that define one of the stacks 114 such that all of their centroids 188, also known as the geometric centers, lie in a plane perpendicular to the surface 38. In this embodiment this plane is parallel to the plane of
It should be noted that the stability of the stack relies on support of the third element 110C being supplied by each of the first element 110A and the second element 110B. Stated another way, without either of the first element 110A or the second element 110B the third element 110C would not be stably supported at the desired angle 130 prior to attachment.
The geometric configuration of the cutting elements 110A, 110B, 110C, specifically the central portion being and modified gilmoid 120 with at least one of the supports 124 extending from one of the plane-defined-surfaces 32A, 32B, aid in the attachment to each other and to the surface 38. This is due to gaps 192 defined between the elements 110A, 110B and the surface 38, and to gaps 196 defined between the elements 110A, 110B and the third element 110C. These gaps 192, 196 aid in attaching of the elements 110A, 110B to the surface 38 and the elements 110A, 110B to the element 110C through a brazing process. Specifically, the gaps 192, 196 encourage wicking and filling thereof with brazing material as well as whetting of the brazing material to the elements 110A, 110B, 110C. The stability of the stack 114 also aids in the brazing process by maintaining the elements 110A, 110B, 110C in the desired positional relationship to each other and the desired angular relationship to the surface 38 during the brazing process. In fact, the stability of the stack 114 permits an operator during a hand brazing process to inadvertently contact the elements 110A, 110B, 110C with the brazing torch or brazing material rod without the stack 114 toppling over or needed to be restacked to continue.
Referring to
The stacks 114 can be attached via brazing to the surface 38 one at a time or as a group, one such group being one or more of the blades 318 and another such group being one or more of the clusters 318. Brazing a plurality of the stacks 114 in a single operation can speed up the manufacturing process. Additionally, brazing the stacks 114 that are positioned adjacent to one another together, provides additional strength to the blades 314 and the clusters 318. The foregoing structure provides cutting devices 300A, 300B that have a repeating structure of the cutting element 110A, 110B, 110C, as opposed to a random configuration. The repeating structure provides more reliability and predictability in cutting rates and durability of the tool than those with randomly positioned and oriented cutting elements.
Another advantage of attaching the elements 110A, 110B, 110C to the surface 38 in the stacks 114 is that the devices 300, 300A, 300B continue to have sharp new cutting edges on the first element 110A and the second element 110B exposed for cutting after the third element 110C has been fractured and/or detached from the device 300, 300A, 300B.
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.
