DEVICE FOR INTERVAL-BY-INTERVAL HYDRAULIC FRACTURING OF STRONG ROCKS Russian patent published in 2019 - IPC E21B43/26 

FIELD: mining.

SUBSTANCE: invention relates to mining, namely to development of gently sloping coal beds, and can be used for their degassing. Device for intermittent hydraulic fracturing of strong rocks, consisting of housing with channel, installed on it elastic sealing elements, between which piston pair is arranged, wherein piston pair working chamber is communicated with said channel, and in its cylinder there is a radial hole with the possibility of communication with the working chamber of the piston pair, which includes a reverse hydraulic shock device installed on the bottom part of the housing, an adapter connected to the wellhead part of the housing, and a rod for connection to the drill rod. Body has a through hole with a tube for supplying working fluid into said reverse hydraulic shock device, which includes a bushing with a striker and a head piece containing a battery and a working fluid distributor. Striker is arranged on tube for supply of working fluid with possibility of axial movement and spring-loaded by return spring. Bushing is connected to the body and a head piece is attached to it by means of thread. In the hammer the groove is made with the possibility of connection to the channel connected to the draining, and to the control channel connected to the working fluid distributor, at that the above tube for working fluid supply is connected to the working liquid distributor and the accumulator by means of the pressure channel. Headguard, sleeve and hammer make working chamber connected with working fluid distributor by drain channel and further through said distributor and additional drain channel with said channel connected with drain. Rod has central hole and is installed with possibility of axial movement inside adapter, in which channel is made with possibility of connection with specified channel of housing and channel connected with specified tube for supply of working fluid.

EFFECT: technical result consists in hydraulic fracturing in wells of complex hypsometry or with low stability of walls, as well as simplified extraction of device from well.

1 cl, 4 dwg