METHOD AND DEVICE TO ELIMINATE DRILL TOOL STICKING Russian patent published in 2012 - IPC E21B31/00 

FIELD: oil-and-gas production.

SUBSTANCE: pipes being extracted are subjected to magnetic pulses induced in pipe fluid by intermittent discharge of capacitor arranged directly in sticking zone. Proposed invention differs from known designs in that electric discharge power is selected to equal W_k=1-6 kJ. Charging unit additionally incorporates coupling locator magnetic system or sticking detector system wherein terminals of measuring or generator coil are connected to one of low-voltage input and to chassis, while condenser power accumulator features total power output of W_c=(W_k/η)≥1.25-7.5 kJ, where η≤0.8 is electrical efficiency of power accumulator. Besides, casing of charging unit in the area of coupling locator magnetic system or sticking detector system is made from nonmagnetic material and features smaller wall thickness. Low-voltage input of charging unit has three terminals while outputs of aforesaid measuring or generator coil are connected in parallel or via isolation capacitor.

EFFECT: time and labor saving.

5 cl, 8 dwg