By a roller cone bit bearing cavity, bearing the runway, dental palm journal, locking elements etc. Generally bearing deputy have large, medium, small and thrust bearing composed of four parts. Large and small bearing radial load, Bearing mainly used to lock and locate the ends of the thrust bearing to withstand high axial loads. The bearing structure pairs, drill Rolling bearings and plain bearings are generally divided into two categories, according to the bearing seal or not, it can be divided sealed and unsealed. With the development of bearing technology in recent years has developed a variety of new bearing as a floating bearing, insert sleeve bearings.

Rolling structure has roller - ball - roller - thrust and roller - ball - small-axis slide - pushing two stops before an adaptation to large-size (12 1/4 ") drill such rolling bearings. accommodate higher operating speed. sealed rolling bearing structure of the drill main GA series and GJ series, W series and K series of drills used in non-sealed bearing. with a sealed rolling bearing, its structure is characterized by the cone at the bottom plane sealing element ('O' ring or metal seals) installed, they can work at 100 ~ 250r / min speed, sealed bearing life than non-sealed bearings. use of non-sealed roller bearing drill W series Although able to adapt to higher speeds but lower bearing service life. The same non-sealed rolling bearing K series air-cooled drill bit, is a mining drill series, bearing the working life is higher than W series drill, drill near the GA series .