Bearing apparatus including a bearing assembly having a continuous bearing element and a tilting pad bearing assembly

Abstract

Embodiments of the invention relate to bearing apparatuses including a bearing assembly having a continuous superhard bearing element including a continuous superhard bearing surface and a tilting pad bearing assembly. The disclosed bearing apparatuses may be employed in pumps, turbines or other mechanical systems. In an embodiment, the bearing apparatus includes a first and second bearing assembly. The first bearing assembly includes a first support ring and a plurality of tilting pads. Each tilting pad is tilted and/or tiltably secured relative to the first support ring. The second bearing assembly includes a continuous superhard bearing element. The continuous superhard bearing element includes a continuous superhard bearing surface facing the plurality of tilting pads and exhibits a maximum lateral width greater than about 2 inches.

We claim: 
     
         1 . A bearing apparatus, comprising
 a first bearing assembly including:
 a first support ring; and 
 a plurality of tilting pads each of which includes a superhard bearing element having a superhard bearing surface, each of the plurality of tilting pads tilted and/or tiltably secured relative to the first support ring; and 
   a second bearing assembly including:
 a continuous superhard bearing element including a continuous superhard bearing surface that generally faces the superhard bearing element of each of the plurality of tilting pads, the continuous superhard bearing element having a maximum lateral width greater than about 12.7 cm. 
   
     
     
         2 . The bearing apparatus of  claim 1  wherein the superhard bearing surface of at least one of the plurality of tilting pads includes at least one of polycrystalline diamond, silicon carbide, silicon nitride, cubic boron nitride, tantalum carbide, reaction-bonded silicon carbide, reaction-bonded silicon nitride, or binderless tungsten carbide. 
     
     
         3 . The bearing apparatus of  claim 1  wherein the maximum lateral width is about 12.7 cm to about 30.5 cm. 
     
     
         4 . The bearing apparatus of  claim 1  wherein the maximum lateral width is about 12.7 cm to about 17.8 cm. 
     
     
         5 . The bearing apparatus of  claim 1  wherein the maximum lateral width is about 17.8 cm to about 25.4 cm. 
     
     
         6 . The bearing apparatus of  claim 1  wherein the continuous superhard bearing element includes a superhard table bonded to a substrate. 
     
     
         7 . The bearing apparatus of  claim 6  wherein the superhard table includes polycrystalline diamond. 
     
     
         8 . The bearing apparatus of  claim 1  wherein the continuous superhard bearing surface includes at least one of silicon carbide or silicon nitride. 
     
     
         9 . The bearing apparatus of  claim 8  wherein the continuous superhard bearing surface includes at least one additional material added to the silicon carbide or silicon nitride, the at least one additional material including at least one of diamond or boron carbide. 
     
     
         10 . The bearing apparatus of  claim 9  wherein the at least one additional material is added to the silicon carbide or silicon nitride in an amount less than about 80 weight %. 
     
     
         11 . The bearing apparatus of  claim 1  wherein the continuous superhard bearing surface of the continuous superhard bearing element and the superhard bearing surface of at least one of the plurality of tilting pads comprise different materials. 
     
     
         12 . The bearing apparatus of  claim 1  wherein the continuous superhard bearing surface of the continuous superhard bearing element includes silicon carbide and the superhard bearing surface of at least one of the plurality of tilting pads includes polycrystalline diamond. 
     
     
         13 . The bearing apparatus of  claim 1  wherein at least one of the superhard bearing surface of at least one of the plurality of tilting pads or the continuous superhard bearing element includes a coating. 
     
     
         14 . The bearing apparatus of  claim 1  wherein at least one the continuous superhard bearing surface of the continuous superhard bearing element or the superhard bearing surface of at least one of the plurality of tilting pads has a surface finish of less than about 0.89 μm. 
     
     
         15 . The bearing apparatus of  claim 14  wherein the surface finish is about 0.13 μm to about 0.25 μm. 
     
     
         16 . The bearing apparatus of  claim 13  wherein the surface finish is less than about 0.064 μm. 
     
     
         17 . The bearing apparatus of  claim 1  wherein the continuous superhard bearing element is brazed to the second support ring. 
     
     
         18 . The bearing apparatus of  claim 1  wherein the first bearing assembly is a stator and the second bearing assembly is a rotor. 
     
     
         19 . A method of operating a bearing apparatus, the method comprising:
 rotating a rotor relative to a stator;   wherein at least one of the stator or the rotor includes:
 a first support ring; and 
 a plurality of tilting pads each of which includes a superhard bearing element having a superhard bearing surface, each of the plurality of tilting pads tilted and/or tiltably secured relative to the first support ring; 
   wherein the other of the stator or rotor includes:
 a continuous superhard bearing element including a continuous superhard bearing surface that generally faces superhard bearing element of each of the plurality of tilting pads, the continuous superhard bearing element having a maximum lateral width greater than about 12.7 cm. 
   
     
     
         20 . A method for manufacturing a bearing assembly, the method comprising
 forming a continuous superhard bearing element that includes a continuous superhard bearing surface, the continuous superhard bearing element having a maximum lateral width greater than about 12.7 cm;   forming a hole in the center of the continuous superhard bearing element;   providing a support ring including a recess configured to receive the continuous superhard bearing element;   attaching the continuous superhard bearing element to the support ring such that the continuous superhard bearing element is secured in the recess of the support ring and the continuous superhard bearing element; and   smoothing the continuous superhard bearing surface of the continuous superhard bearing element to exhibit a surface finish of less than 0.64 μm.   
     
     
         21 . The method of  claim 20  wherein forming a continuous superhard bearing element that includes a continuous superhard bearing surface includes forming the continuous superhard bearing surface from a polycrystalline diamond table that is bonded to a substrate.