Abstract: A rock bit having a cutter retained on an axle through an array of rolling members interposed within an interior annular space therebetween, and a passage defining a passage wall for inserting the rolling members from the exterior of the bit to the interior space. A plug for closing the passage, and retaining the members in the space is welded at an end adjacent the bit exterior and a contamination excluding snap ring is interposed between the plug and the passage wall for preventing weld slag or weld material from entering the passage.

Abstract: A sealing system for a rotary rock bit retains lubricant inside the bit and acts as a barrier to the pulverized cuttings and other materials in the borehole to prevent the materials from entering the bearing area through the cone mouth opening of the rolling cone cutter. A protecting ring is positioned outside of an elastomer seal element. Both the protecting ring and the elastomer seal element are positioned in the cone mouth opening. The protecting ring is positioned in the cone mouth opening with a slight interference fit. This allows the elastomer seal element to be protected from the hostile drilling environment and increases seal life. The protecting ring retards materials in the borehole from contacting the seal element. The sealing system is provided without reducing the bearing capacity of the bit's bearing system.