API factory oil well tricone drilling bits for hard rock formations

How to Choose Tricone Drill Bits

According to the lithology of the drilled formation, the following principles should be followed when selecting the type of drill bit:

a. In the shallow well section where the rock is cemented and loose, the drilling speed of the drill bit and the prevention of mud packs should be considered;

b. In the deep well section where the trip is long, the footage of the drill bit should be considered;

c. When the outer row teeth of the drill bit out of the well are severely worn, a bit with gauge teeth should be used;

d. In the easy deviating well section, a bit with small slip and many short teeth should be used;

e. Wedge-shaped tooth drills should be used when selecting insert drills;

f. For diamond limestone, it is advisable to use double-cone-tooth and projectile-shaped tooth drill bits;

g. When there is more shale in the formation or the density of drilling fluid is higher, a bit with a larger slip amount should be selected;

h. When the stratum is limestone or sandstone, and a bit with a smaller slip amount should be selected;

i. When drilling hard and highly abrasive stratum, it is advisable to use pure rolling button and double bevel bit.

In order to optimize the hydraulic parameters of bit, the longer nozzle and unequal diameter combined nozzle bit should be preferred.