WORKING SHOE Russian patent published in 2025 - IPC E21B37/00 

FIELD: construction of wells.

SUBSTANCE: invention relates to the field of well construction and is intended for the well shaft development during the oil and gas wells casing. Device includes a housing with a cylindrical part with a connection thread from above for connection to a casing string, which is equipped with a central feedthrough hole and side flushing holes. Tip with skewed cone is secured to bottom part of the cylindrical housing. Said tip has central flushing orifice and, at least, three free running rollers fitted on rigid axles with bearings at their ends. Rollers are evenly equipped throughout the outer surface with hard-alloy teeth and have length equal to at least two diameters of freely rotating rollers along hard-alloy teeth. Two side flushing orifices are directed to rollers. Outer diameter of working shoe exceeds diameter of shoe housing along hard-alloy. Shoe is made of easily drilled material.

EFFECT: improving reliability of lowering and installation of casing string in complicated borehole of the well; providing reliable passage of narrowed sections of the shaft with development without jamming and shrinkage; simple design.

1 cl, 1 dwg