WORKING SHOE OF INTERMEDIATE COLUMN Russian patent published in 2022 - IPC E21B37/00 E21B10/26 

FIELD: well construction.

SUBSTANCE: invention relates to the field of well construction and is intended for the equipment of the bottom of the casing string in order to guide it along the wellbore with the possibility of working out unstable sections of the wellbore with zones of shedding and rock falls. The device includes a hollow body with a cylindrical part with a connecting thread on top for connection with an intermediate casing, provided with a bottom flush hole and side flush holes and blades. The end part of the shoe is made concave inside. The guide part of the shoe from the outside from the bottom is made of a radius. Grooves are made on the surface concave inside and the radius guide part in such a way that the working surfaces of the hard-alloy cutters soldered in the grooves are installed at the same level with the working side surface of the blades. The working side surface of the blades is reinforced with hard-alloy grit. The shoe is made of cast iron, and the outer diameter along the blades is 2-5% less than the diameter of the well.

EFFECT: reliability and simplicity of design are ensured, large fragments are excluded when drilling out the shoe, drilling time is reduced.

1 cl, 2 dwg