DEVICE FOR FORMATION OF DIRECTIONAL FRACTURES IN WELLS Russian patent published in 2021 - IPC E21C37/06 E21B43/267 

FIELD: mining.

SUBSTANCE: invention relates to mining and can be used to form cracks in wells for the purpose of degassing coal and salt layers, separating blocks from massifs, extracting valuable crystalline raw materials and building stone, collapsing roofs. The device includes a hollow cylindrical body with a channel for supplying a working fluid. Elastic sleeve coaxial to the body, wedges, valve, holes in the walls of the body, communicating its cavity with the space under the elastic sleeve. An elastic sleeve is attached to the body at both ends. Wedges are installed at the end of the body, free from the elastic sleeve, in a plane passing through its axis. The valve is made in the form of an elastic sleeve put on the body between the elastic sleeve and the wedges. Holes are made in the body, communicating its cavity with the space under the elastic sleeve, and longitudinal slots between the wedges, which make it possible to expand its lateral surface to create a given force of pressing the wedges into the borehole walls. Inside the body, with the exception of longitudinal movement relative to it, a glass of elastic material is placed in such a way that it overlaps the indicated slots.

EFFECT: invention increases efficiency of the formation of directional cracks in the wells due to the simultaneous action on the rock mass with hydraulic pressure, the expansion of the borehole walls and the force of pressing wedges, regardless of the depth of penetration of the latter into the rock.

2 cl, 4 dwg