DEVICE FOR EXTRACTION OF WHIPSTOCK FROM WELL Russian patent published in 2020 - IPC E21B31/20 

FIELD: soil or rock drilling.

SUBSTANCE: invention relates to drilling and overhaul of oil and gas wells and can be used in construction of multi-hole wells and conversion of existing wells into multi-barrel wells. Proposed device comprises barrel with fishing hook for reciprocal recess of whipstock and with possibility of connection with pipe string. Stem is hollow with a radial channel in the lower part above the fishing hook made perpendicular to the device axis on the opposite side relative to the fishing hook. Fishing hook comprises body and barb made integral. Upper and lower surfaces of the housing are made at angle of 10–15° to transverse axis of the device. Upper surface of the body is equipped with a flushing channel connected to the hollow shaft. Small-toothed beak has projections located parallel to the axis of the device and tapering at angle of 20–25° to the tip of the barb. Protrusions are made with possibility of interaction with mating flanges in recess of whipstock. Device is equipped with a hydro-vibrator.

EFFECT: enlarging process and functional capabilities, facilitating orientation of fishing hook on sample of whipstock and its cleaning from contamination, facilitating faster and more reliable grip of whipstock without using geophysical batch, providing fixation and retention of the whipstock in the process of extraction from the well, excluding emergency cases, necessity to perform works on disconnection of the device when it is impossible to remove the whipstock from the well, improved manufacturability and structural strength.

4 cl, 7 dwg