Oil filed bearing sealed with heat and oil resistant thrust metal seal or radial O-ring.
The bearing type is as follows:roller bearing ball bearing,journal bearing,radial journal bearing.
Thrust shoulder and radial journal bearing surfaces are applied with hard alloy.
The bearing is filled with grease to reduce friction coefficient in the bearing,its overhear and wear.
BIT CUTTER STRUCTURE
Depending on the formation hardness,these bits use tungsten carbide inserts or steel teeth as their cutting structure.
Hardfacing is applied along steel teeth,including those in the heel row.The hard alloy consists of tungsten carbide grains of different sizes.Enhanced thick hardfacing is applied on sides,faces and noses of teeth to provide maximum wear resistance and increased ROP.
In Steel Tooth bit the protected with tungsten carbide compacts.