HDD - Drilling tools Roller bit2013-07-10
The structure of roller bit
The roller bit is made of roller, tooth, roller shaft, bearing, palm, drill bit body, nozzle and oil storage lubrication seal system.
Oil storage pressure compensating system keep the oil pressure in bearing bore is balanced with the pressure of drilling fluid string. When the pressure of bearing bore is decreased, the lubrication oil is replenished to the bearing bore by the drilling fluid string pressure in oil storage; when the oil pressure is raise, then it will flow into the oil storage cup. But the effective seal is the key.
Impacting and crushing effective
When the roller bit works, the roller rolls, the single tooth and double tooth are alternately touching the bottom well make drill bit produce the longitudinal rolling. The drill bit produce impacting load and drilling pressure to the rock, to the bottom rock produce impacting and crushing effective.
Gliding and shearing effective