WHIPSTOCK FOR REENTERING SIDE TRUNK OF MULTIPLE WELL Russian patent published in 2018 - IPC E21B7/08 

FIELD: soil or rock drilling.

SUBSTANCE: invention relates to the field of drilling and capital repairs of oil and gas wells. Whipstock includes a housing with a guide surface on top and an actuating element capable of moving in the housing between the transport position and the locking position and having a surface at the upper end for engagement with obstacles encountered in the casing string. Guide surface of the housing is designed to interact with the drilling tool after the installation of the housing in the casing. Housing is provided on the outside with sealing elements, that are adapted to interact with the casing in the locked position, and inside with diametrically and inclined chambers interconnected, which are also communicated with the pipe string. Diametrically chamber is provided with a hermetically inserted retainer spring-loaded in the direction of the guide surface with an inclined surface on top of the guide surface, made with the possibility of extension of the sealing elements to seal the inner space of the casing when creating pressure in the chambers and the extension of the actuating element in the position of fixation. Inclined from the axis of the housing camera, directed toward the guide surface, is provided with a radial channel. Executive element is hermetically inserted into the inclined chamber in the transport position flush with the body, blocking the radial channel from the inside, fixed in the transport position by the locking mechanism and made with the possibility of extension when creating pressure in this chamber with the opening of the radial channel and its engagement with the bottom edge of the window previously opened in the casing string. Actuating element on top is provided with a bevel in the locking position, having an angle corresponding to the angle of the guide surface, and is adapted to interact with the inclined surface of the clamp, keeping it from being pulled out in the transport position, releasing it in the locked position and returning it to the transport position with fixing when the actuator is moved inside the case.

EFFECT: full whipstock extraction is provided without reducing the main trunk bore, extending the functionality, simplifying the work.

1 cl, 3 dwg