Image Number 2 for United States Patent #5253939.
Cylindrical bearing pads are insertable into bearing pad recesses formed in a receiving surface of a bearing pad retainer in a load-carrying structure. The bearing pads have an insertion end which is fixed into the bearing pad recess by brazing or by interference fitting and a bearing end which projects from the receiving surface and terminates in a bearing face. The bearing face has a periphery which encircles the bearing face and an indentation having a perimeter formed centrally in the bearing face. An annular flattened area encircles the indentation forming an effective bearing contact area between an outer border of the flattened area and the perimeter of the indentation. When the indentation is filled with drilling fluid, lubrication is provided to an opposed bearing face of an opposing bearing pad. The indentation can be filled with drilling fluid or some other material with a higher heat storage capacity than polycrystalline diamond to provide temperature modulation for storing heat produced at the bearing face. When filled with a material, the indentation also serves to dissipate heat to reducing the length of a path of heat when the heat is conducted to cooler areas of the bearing face. Alternate embodiments include bearing faces with single or plural indentations of various shapes.