Patent Application
20140064646
1. Field of the Invention
The invention is directed to friction reducing devices. In particular, the invention is directed to low-friction, abrasion resistant replaceable friction reducing bearing surfaces.
2. Background of the Invention
Many industries, including but not limited to oil well drilling, machining, mining, quarrying, and transportation, use mechanisms that need to work under high pressure and high temperature conditions. Furthermore, parts of the mechanisms often rub against each other or external surfaces and, therefore, a low friction, abrasion resistant surface in these parts is desired.
One solution, for example, is a bearing surface comprised of Polycrystalline Diamond Compact (PDC), a synthetic diamond that performs under harsh conditions. PDC is diamond grit that has been fused together under high-pressure, high-temperature conditions in the presence of a catalytic metal. The extreme hardness, wear resistance, and thermal conductivity of diamond make it an ideal material for bearings. Individual diamond crystals cleave quite easily when struck parallel to certain planes (the process used to facet diamond gemstones takes advantage of these relatively weak planes). Diamond sintering overcomes the problem of weak planes in diamond gemstones by bonding a mass of small diamond particles onto a larger, coherent structure. Sintered diamond provides greater toughness and durability than single crystals because the individual crystals in a sintered body are randomly oriented. This prevents cracks from propagating along the weak planes where traditional diamond crystals cleave most easily. Sintered diamonds also provide more uniform wear than a single crystal, while maintaining similar thermal conductivity and hardness properties. All of these factors combine to make sintered diamond the ideal material for many bearing applications.
However, overtime, PDC bearings do wear out and can become damaged from intensive use. The PDC bearings are usually embedded into the device by welding and, therefore, in order to replace the PDC bearings, the parts must be removed from operation and transported to a specialized facility that is able to remove the worn out PDC bearings and replace them with new bearings. The process is both costly and time consuming. Furthermore, the repeated heating and cooling needed to replace the bearings causes excessive stress on the devices. Additionally, the welded or brazed bearing pads currently used during refurbishment cannot maintain precision tolerances, especially after multiple replacements. Therefore, it is desirable to have a replaceable low-friction, abrasion resistant bearing surface capable of being replace quickly on-site.
The present invention overcomes the problems and disadvantages associated with current strategies and designs and provides new tools and methods of providing replaceable low-friction, abrasion resistant bearing surfaces.
One embodiment of the invention is directed to a replaceable bearing surface. The replaceable bearing surface comprises an outer housing and a low-friction, abrasion resistant button secured within the outer housing. The outer housing is adapted to be inserted into and removed from a device without damaging the device.
In the preferred embodiment, the button is comprised of Polycrystalline Diamond Compact (PDC). Preferably, the outer housing is comprised of 41/30 steel. The button is preferably press fit into the outer housing. Preferably, the outer housing has a notched grip portion and the outer housing has a threaded portion. The threaded portion of the outer housing is preferably adapted to mate with a threaded recess in the device.
In the preferred embodiment, the button is hemispherical. Preferably, the outer surface of the button extends beyond at least one surface of the outer housing. Preferably, when installed, button extends beyond an exterior surface of the device.
Another embodiment of the invention is directed to a low-friction, abrasion resistant system. The system comprises a device having at least one recess, a plurality of replaceable bearing surfaces adapted to be inserted into and removed from the at least one recess without damaging the device, each replaceable bearing surface comprising an outer housing, and a low-friction, abrasion resistant button secured within the outer housing.
Preferably, the button is comprised of Polycrystalline Diamond Compact (PDC). In the preferred embodiment, the outer housing is comprised of 41/30 steel. Preferably, the button is press fit into the outer housing. In the preferred embodiment, the outer housing has a notched grip portion and a threaded portion. Preferably, the threaded portion of the outer housing is adapted to mate with a threaded recess in the device.
Preferably, the button is hemispherical. Preferably, the outer surface of the button extends beyond at least one surface of the outer housing. In the preferred embodiment, when installed, button extends beyond an exterior surface of the device. The device is preferably one of a drill bit, a reamer, a cam shaft, a bearing, or an axle.
Another embodiment of the invention is directed to a method of installing and removing a replaceable bearing surface without damaging the device.
Other embodiments and advantages of the invention are set forth in part in the description, which follows, and in part, may be obvious from this description, or may be learned from the practice of the invention.
The invention is described in greater detail by way of example only and with reference to the attached drawing, in which:
As embodied and broadly described herein, the disclosures herein provide detailed embodiments of the invention. However, the disclosed embodiments are merely exemplary of the invention that may be embodied in various and alternative forms. Therefore, there is no intent that specific structural and functional details should be limiting, but rather the intention is that they provide a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present invention.
A problem in the art capable of being solved by the embodiments of the present invention is replacing worn out bearing surfaces quickly and on-site. It has been surprisingly discovered that providing a replaceable low-friction, abrasion and impact resistant bearing surface allows technicians to replace worn out bearing surfaces themselves without transporting the device to a specialty facility.
Preferably, outer housing 105 is comprised of 41/30 steel, however other steels or other materials can be used for outer housing 105. For example, nylon, other metals, plastics, carbon-fiber, or other naturally occurring or manmade materials. As can be seen in
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Other embodiments and uses of the invention will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. All references cited herein, including all publications, U.S. and foreign patents and patent applications, are specifically and entirely incorporated by reference. It is intended that the specification and examples be considered exemplary only with the true scope and spirit of the invention indicated by the following claims. Furthermore, the term “comprising of” includes the terms “consisting of” and “consisting essentially of.”
This application claims priority to provisional application U.S. Provisional Application Ser. No. 61/696738, filed Sep. 4, 2012, and entitled “LOW-FRICTION, ABRASION RESISTANT REPLACEABLE BEARING SURFACE,” which is specifically and entirely incorporated by reference.
| Number | Date | Country | |
|---|---|---|---|
| 61696738 | Sep 2012 | US |
