METHOD AND DEVICE FOR LATERAL CORING FROM THE WALL OF A NON-CENTERED SECTION OF A CASING STRING IN AN INCLINED WELL Russian patent published in 2022 - IPC E21B49/06 

FIELD: oil and gas industry.

SUBSTANCE: invention relates to the oil and gas industry, to the means of lateral sampling of cores from the walls of cased wells. According to the method, a device assembly is assembled at the wellhead, including a milling perforator, an orientation docking module, a rotating cable lug, a three-wire logging cable is connected to ground control equipment through a control panel and to a power transformer, preliminary calibration work is performed with the orientation module to determine the position of the drill with a cutter in zone with minimum or maximum cement thickness. The assembly is lowered on a three-wire logging cable into the well to the depth of coring, the assembly is rotated around its axis by turning the electric motor of the milling perforator on and off, using the torque pulse from the rotor of the electric motor that occurs during startup, until the drill with the cutter is installed on the surface of the casing string in the specified zone, press against the borehole wall and start milling the column in the place of the minimum or maximum cement thickness, while taking a sample of rock or cement of the greatest length. The device for lateral selection contains a docking orientation module, including a head for connection with a rotating cable lug, a body, an eccentric load in the rolling bearings, a potentiometric load position resistance sensor, a coupling for connection with a milling perforator, electrical wiring. The ground equipment of the control panel contains a transformer with a voltage switch, a rectifier bridge, a rectifier bridge switch, a resistance bridge, a microammeter, a milliammeter with a shunt, a DC polarity switch, a three-phase voltage switch, an ammeter, a power step-up transformer is connected to the control panel, which transmits three-phase current electricity to the electric motor of the milling perforator along the armor and two cores of the logging cable, the milling perforator includes an electromagnetic needle valve for adjusting the feed of the drill with a cutter and a potentiometric resistance sensor for controlling the axial movement of the drill with a cutter. The winding of the needle valve and the potentiometric resistance sensor are connected in series through a diode of positive polarity through the third core of the logging cable with a polarity switch, switching the polarity to negative is connected through a diode to the third core of the logging cable, the potentiometric resistance sensor of the position of the eccentric weight of the orientation module of the device.

EFFECT: increasing the efficiency and reliability of the method and device due to the adjustable orientation of the drill with a cutter in the non-centered part of the casing string in an inclined well in an area with a minimum cement thickness when lateral sampling of elongated rock samples and with a maximum cement thickness when selecting elongated cement samples.

2 cl, 4 dwg