WEDGE-LIKE WHIPSTOCK Russian patent published in 2006 - IPC E21B7/08 

FIELD: drilling equipment, particularly to drill oil and gas wells and to cut windows in casing pipe, as well as to provide transport position to whipstock during emergency extraction thereof from the well.

SUBSTANCE: whipstock comprises wedge-like deflection means and support with inclined surfaces defining gutter and extension correspondingly. The wedge-like deflection means has cylindrical thrust part fixedly secured to deflecting part thereof. Window for anvil receiving is created in thrust part of the wedge-like deflection means. The anvil is provided with slot arranged from inner side thereof. The slot corresponds to extension on inclined support surface. Outer anvil side has teeth shaped as flat supporting notches. The support consists of tapered upper part and widened lower part and made as one-sided thrust wedge arranged in cavity formed in widened part of the wedge-like deflection means. Upper tapered part of the support has L-shaped rest connected with wedge-like deflection means by clamp. The thrust part of the wedge-like deflection means has two radial-stop members located from gutter side. The anvil is arranged from side opposite to side of radial-stop member location. The anvil teeth face upwards by inclined parts thereof. Widened part end is spherical. Upper part of deflecting part of the wedge-like deflection means is provided with hole located along rear surface thereof. Through groove extends at an angle to upper deflecting part of the wedge-like deflection means.

EFFECT: increased tightness of device fitting inside well or connection thereof to inner casing pipe wall regardless of pipe wall thickness and inner casing pipe diameter, increased ability of whipstock control during lowering thereof to well face and securing inside the well, possibility of dynamic deflection wedge angle setting and increased quality of window cut in casing pipe wall.

6 dwg