Relation between forward thrust on a perforator and its characteristics, the bit shape, and the rock-breaking process

Conclusions

• 1. The forward thrust depends on the parameters of the perforator and bit and on the characteristics of the rock being drilled.

• 2. The optimal forward thrust should ensure that the perforator operates so that in each cycle the body drops on to the shoulder before the bit emerges to the level of the preceding impact, and the withdrawal of the body should be equal to the depth of penetration per impact.

• 3. The equations found above can be used to determine the forward thrust in the design of feed mechanisms, as well as to elucidate the laws of change of this thrust in drilling with a given perforator and various bits, or in various rocks: this may prove useful in the design of drilling machines with automated setting to optimal drilling conditions.