General principles of selection of drilling bits
Whether the selection of the roller cone bit is reasonable has a great relationship with the drilling construction cost. Therefore, it is very important for the water well drilling rig to reasonably select the drill bit according to the construction situation. At present, the roller cone bits used in water well drilling are all oil drilling specifications, among which the three-cone bit is the most common, but only self-made group-welded roller cone bits can be used in the construction of special water wells.
Rocks can be roughly divided into three types: one is brittle rock, such as limestone, sandstone, granite, diorite, etc.; one is plastic rock, such as mudstone, argillaceous shale, etc.; there is an intermediate ductile and brittle rocks, such as argillaceous cemented sandstone, etc. The roller cone bit is more suitable for drilling in hard and brittle rock, and breaks the rock by impact and crushing.
