SHOCK-ROTATIONAL DEVICE FOR DRILLING COLUMN Russian patent published in 2018 - IPC E21B4/02 E21B28/00 

FIELD: drilling of soil or rock.

SUBSTANCE: invention relates to drilling techniques, in particular to shock-rotational devices for a drill string, intended for creating hydromechanical pulses. Device includes a gerotor mechanism, a valve device, an axial support of the rotor of the gerotor mechanism, and a generator of hydromechanical impulses. Axial support is made in the form of two support disks, the upper disk of the axial support is made with the channel "b" and is fastened to the bottom end of the rotor, the lower disk of the axial support has a channel "c" and is fixed in the bottom of the stator. Friction surfaces of the two support discs are made of a wear-resistant material with a hardness of more than 50 HRC. Valve device is made in the form of two valve elements, the first valve element is made in the form of a disk with "R" radius, equal to the radius of the troughs of the rotor teeth, which is coaxially mounted on the upper end part of the rotor perpendicular to its axis, and the second valve element, made in the form of a cup, is mounted in the upper part of the stator coaxially with it, fixed from the rotation and pressed against the first valve element by a spring. In the second valve element, a figured slot is provided for the passage of the drilling fluid, when the gerotor mechanism is operated, it is periodically partially overlapped by the first valve element moving along with the rotor, creating a pressure pulsation. Shape of the curved slot is limited by arcs drawn by the radii from point O1 located at a distance "e" from the stator axis, with "e" being the eccentricity of the rotor in the stator, the arc radii of the shaped slot are: R1=R-e, R2=R+e+f, f – width of the gap, which is not overlapped by the first valve element, f=0.04R, angle g limits the length of the slot and can be made within 120–180 degrees.

EFFECT: increased reliability and durability, reduced pressure losses, and also increased efficiency of use of pulsation of pressure of a liquid and simplified works on service are provided.

1 cl, 2 dwg