Application of exsplosives for perforating, blasting (torpeding) and fracturing in the petroleum industry

The increasing production of oil and gas has an exceptional economical significance. The completion technology is a very Important stage within the process of drilling, testing and bringing a well to the exploitation stage. The productivity of a well and the final yield of the completed hydrocarbon layer depend on a proper selection of the completion method. Compared with the bed size, the surface of the borehole where the fluid flow In is disproportionately very small. The main part of resistance to the fluid flow is present in this place. For that reason all factors opposing the flow In this place have to be reduced to the smallest values. Explosives are used for increasing the productive capacity of oil and gas producing wells since the nineteenth century. To expand the existing and create new fractures in the oil and gas beds, special torpedoes charged with a brisant explosive were used. From the aspect of permeability of the zone adjacent to the borehole, the most favorable production of gas and oil is achieved by open hole completion, if, of course, the properties of pierced layers and well construction allow such way of production. However, by that way of completion, the adjacent zone exerts an additional resistance to the liquid flow due to damages arised from drilling. In cased holes a contact with the bed is established by the perforating technique. This procedure causes additional damage of the narrow zone around the borehole and the perforation Itself presents an additional resistance. This contribution describes the possibility of an increased yield of the oil and gas wells by using a special explosive and applying special methods of fracturing and blasting the productive series in the oil and gas beds.