How to choose tricone drill bits for mining?
The design of the tricone bits must adapt to the characteristics of the rock to be drilled, and different design structures are adopted for the roller cone bit used for different types of rock. The tricone drill bit used for soft rock drilling usually adopts a long tooth height, and the tooth distribution interval is sparse, so as to facilitate the rolling and scraping of the drill bit on the rock surface, so as to achieve the purpose of rapid rock crushing. For the hard rock drill, high toughness spherical tooth alloy is used, the teeth are relatively dense, and the rock is mainly rolled during the drilling process, so as to reduce sliding scraping as much as possible. In order to reduce the wear of the rock on the alloy, the alloy teeth are commonly used in the roller cone bit.
Bearing system of mining roller drill bit
The mining roller drill bit requires a lot of propulsion force during the piercing process, so the bearing strength and structural design requirements are very high. Large diameter roller three-cone bits generally use the roller - ball - roller (RBR) bearing system: smaller diameter roller three-cone bits use the roller - ball - slide (RBF) bearing system. The radial force generated by these two bearing systems in the drilling process is mainly by the large roller bearing load, the small roller or sliding bearing plays an auxiliary role, and the axial force is mainly borne by the front plane thrust bearing, with the deepening of the drilling hole and the wear of the tricone drill bit, the axial force is also transmitted to the rear thrust bearing and ball bearing, so that the service life of the tricone drill bits is extended.
