WEDGE-TYPE WHIPSTOCK Russian patent published in 2000 - IPC

FIELD: bore-hole drilling equipment. SUBSTANCE: wedge-type whipstock can be used for enlarging through-bore for tool at cutting out window in producing pipe string, at drilling second bore-hole, and for using subsurface equipment at further operation of well. Wedge-type whipstock has deviating wedge, support, slips with teeth in external surface. Shear bolt contains hinge which is made in the form of half-coupling possessing non-resilient part and resilient part. Non-resilient part of half-coupling is rigidly connected with deviating wedge. Resilient part of half-coupling is located in support body of cylindrical configuration with possibility of swinging motion for half-coupling relative to surface of pin which connects them. Support is made in the form of body of cylindrical configuration and thrusting wedge which is seated in clearance between resilient part of half-coupling and body. Thrusting wedge is secured by shear bolt. Half-coupling is located in upper part of support in body window. Lower resilient part of half-coupling can advance towards wall of casing string through window made in rear part of support body of cylindrical configuration. Slip on internal surface is made in the form of protrusion of trapezoidal configuration. Part of support made in the form of thrusting wedge has slot and its configuration corresponds to that of protrusion. Wedge-type whipstock ensures higher reliability at efficient application in operation due to full guarantee of tight contact between deviating wedge and diametrically opposite walls of casing string, thus allowing for creation of preset angle of cutting by tool for example in cutting out window in producing string. EFFECT: higher efficiency. 5 dwg