DEVICE FOR DEEPENING OF WELL BOTTOM Russian patent published in 2020 - IPC E21B37/00 E21B25/10 

FIELD: oil and gas industry.

SUBSTANCE: invention relates to oil industry and can be used in deepening of well bottom in process of its operation with possibility of core sampling. Proposed device comprises hollow body, plunger arranged inside said hollow body, spring, annular bead and valve. Plunger is equipped with a partition from above, and below the partition the plunger is equipped with a valve made in form of a seat and a sealing plate with a guide rod. Guide rod is tightly fitted from above in a sealed way into the plunger partition, and the plate is spring loaded upwards from the partition. From below hollow body is equipped with bottom-hole cutter, above which annular shoulder is made in hollow body. Above the annular collar in the hollow body there is an internal annular recess, in which a petal core-cutter is installed. Inside the plunger there is a receiving chamber divided by a valve into upper and lower parts. Force of compression of valve spring is less than force of compression of spring of hollow housing, wherein diameter d of valve plate is half an inner diameter D of plunger, and valve seat is made for cone, tapering from bottom to top with taper angle of 130°, wherein in transport position spring is arranged inside hollow housing and presses plunger from partition wall to hollow housing, and from below plunger interacts with annular collar of hollow housing, which limits axial movement of plunger downwards, lobes of core-cutter are forced spring-loaded radially outward by plunger in annular sample of hollow housing, and in working position, plunger has the possibility of limited axial movement upwards relative to hollow housing and release of petals of core-cutter from interaction with plunger and their radial compression inside.

EFFECT: higher reliability of the device, broader functional capabilities, higher quality of cleaning the well bottom from foreign objects, higher efficiency of the device.

1 cl, 3 dwg