VIBRATOR FOR A DRILLING STRING Russian patent published in 1995 - IPC

FIELD: drilling. SUBSTANCE: oncoming cone-shaped turnings are made on internal surface of the shaft in stalled in the casing. Seats are made in the place, where the turnings are come across. The seats are used for relief valve, provided with openings for hydraulic communication between axial shaft passage and annular cavity between the seat and casing. A partition is able to pass through the seat of the relief valve, and the diameter of the valve is smaller than that of the partition and shaft axial passage. Inlet passages are made if the form of jets. The vibrator is provided with a trap for the relief valve installed under shaft support. EFFECT: effective influence on sticking area. 2 cl, 1 dwg