CASING PIPE SHOE Russian patent published in 2006 - IPC E21B17/14 

FIELD: mining, particularly to lower casing pipe in well bore during well construction.

SUBSTANCE: casing pipe shoe comprises hollow cylindrical body provided with connection thread at upper part thereof. The connection thread is adapted to connect the body to casing pipe. Guiding plug having axial channel, through axial slots and conical lower part is fixedly secured to the body. The shoe also has deflecting members and fingers. The deflecting members are made as bent double-armed levers having T-shaped cross-sections. Each lever includes base and support plate. Outer surface of support plate defines round billet sector in cross-section. Lever bases are located in through axial slots of guiding plug. Guiding plug and lever bases are provided with radial channels for finger receiving. The levers are uniformly installed on outer side surface of guiding plug by means of fingers and may rotate about the fingers. Major lever arms are directed towards lower end of guiding bush, minor ones are directed towards the body.

EFFECT: increased reliability of casing pipe lowering and installation in abnormal well bore.

2 cl, 4 dwg