Earth boring bit with gridded ferrous bearing surface

Abstract

A rolling cone cutter earth boring bit is provided with a bearing surface having a substantial amount of anti-galling material throughout the load area of the bearing. A rough machined bearing surface is provided with either a male or female gridded surface through the use of a fine-toothed knurling tool. Anti-galling material is applied to the gridded surface. The bearing is heat treated by conventional quench and temper procedures to provide strength to the ferrous alloy; however, special heat treating and/or carburizing is not required. Excess anti-galling material is removed by machining and/or grinding the bearing surface until a network or grid of the ferrous material is clearly discernible. The bearing provides adequate support for applied loads and substantial amounts of anti-galling material for boundary layer lubrication situations in close proximity to the load bearing area.

Dependencies are inferred from the claim text.