From Alexandria, Virginia, VerticalNews journalists report that a patent by the inventors Scott, Shawn C. (Payson, UT); Johns, Jeffrey A. (Mapleton, UT); Sexton, Timothy N. (Genola, UT); Cooley, Craig H. (Saratoga Springs, UT), filed on March 11, 2013, was published online on December 31, 2013.

The patent's assignee for patent number 8616304 is US Synthetic Corporation (Orem, UT).

News editors obtained the following quote from the background information supplied by the inventors: "Subterranean drilling systems that employ downhole drilling motors are commonly used for drilling boreholes in the earth for oil and gas exploration. Subterranean drilling systems typically include a housing enclosing a downhole drilling motor operably connected to an output shaft. One or more thrust-bearing apparatuses may also be operably coupled to the downhole drilling motor for carrying thrust loads generated during drilling operations.

"Each thrust-bearing apparatus may include a stator that does not rotate and a rotor that is attached to the output shaft and rotates with the output shaft. The stator and rotor may each include a plurality of superhard bearing elements or inserts. Each superhard bearing element may be fabricated from a polycrystalline diamond compact ('PDC') that provides a diamond bearing surface that bears against other diamond bearing surfaces during use.

"In a conventional PDC thrust-bearing apparatus, a thrust-bearing assembly can include a steel support ring that may be configured to accept a number of superhard bearing elements. The superhard bearing elements may be made from a polycrystalline diamond ('PCD') layer formed on a cemented tungsten carbide substrate. The superhard bearing elements may then be brazed into the support ring using a brazing process.

"Brazing the superhard bearing elements into the support ring involves high temperatures that can damage (e.g., graphitize) the polycrystalline diamond of the superhard bearing elements and can also cause the bearing ring to warp. In addition, the support ring and superhard bearing elements should be very clean in order to achieve a brazed joint between the support ring and superhard bearing elements with sufficient strength to withstand the forces applied to the superhard bearing elements during drilling operations. Despite best efforts, brazed joints may, nonetheless, fail during use or testing.

"Therefore, manufacturers and users of bearing apparatuses continue to seek improved bearing apparatus designs and manufacturing techniques."

As a supplement to the background information on this patent, VerticalNews correspondents also obtained the inventors' summary information for this patent: "Various embodiments of the invention relate to bearing assemblies configured for selective removal and replacement of superhard bearing elements and bearing apparatuses (e.g., thrust-bearing apparatuses and radial bearing apparatuses) that may utilize such bearing assemblies. The disclosed bearing assemblies may be used in a number of applications, such as downhole motors in subterranean drilling systems, directional drilling systems, roller-cone drill bits, and many other applications.

"In an embodiment, a bearing assembly includes a support ring and a retention ring assembled with the support ring. The retention ring includes a plurality of through holes. The bearing assembly further includes a plurality of superhard bearing elements, with each superhard bearing element inserted partially through and projecting from a corresponding one of the through holes of the retention ring. The retention ring and each superhard bearing element are collectively configured to restrict displacement of each superhard bearing element beyond a selected position in a direction away from the support ring.

"Other embodiments include bearing apparatuses that may utilize any of the disclosed bearing assemblies and downhole motors for use in drilling systems that may utilize any of the disclosed bearing apparatuses.

"In an embodiment, a method of refurbishing a bearing assembly is disclosed. The method includes providing the bearing assembly in a subterranean drilling system. The bearing assembly includes a support ring and a retention ring assembled with the support ring. The retention ring includes a plurality of through holes. The bearing assembly further includes a plurality of superhard bearing elements, with each superhard bearing element inserted partially through and projecting from a corresponding one of the through holes of the retention ring. The retention ring and each superhard bearing element are collectively configured to restrict displacement of each superhard bearing element beyond a selected position in a direction away from the support ring. The method includes uncoupling the retention ring from the support ring, selectively replacing one or more of the plurality of superhard bearing elements with one or more replacement superhard bearing elements, and coupling the retention ring and the support ring together with the one or more replacement superhard bearing elements therebetween.

"Features from any of the disclosed embodiments may be used in combination with one another, without limitation. In addition, other features and advantages of the present disclosure will become apparent to those of ordinary skill in the art through consideration of the following detailed description and the accompanying drawings."