The process of crack propagation during rotary percussion drilling of hard rocks

Rotary percussion drilling determines the possibility of reducing waste and intrusion of foreign objects into the solution. It reduces drilling costs and increases the processing speed of the resulting product, and also contributes to the high-quality result at the beginning of the drilling string project design. Reducing the number of cracks decreases the amount of rock used and improves the quality of the resulting product. The novelty of the study lies in development and practical application of fibreglass drilling strings that provide reduced energy consumption for drilling and increased elasticity. The authors show that the use of such strings makes possible to shorten the time of field development and increase the yield in difficult geological conditions. Establishment of strings made of polymeric materials and composite structures can significantly reduce the number of cracks in hard rocks. This determines the conditions for the environmental friendliness of the entire production process, the gradual reduction of waste rock usage and increase in the secondary use of oil production materials.