LINER SHOE VALVE Russian patent published in 2012 - IPC E21B17/14 E21B34/12 

FIELD: oil-and-gas production.

SUBSTANCE: liner shoe valve comprises body with central flow channel and seat. Space under shoe vale is communicated with outer space, and valve made up of plug and furnished with push rod. Said valve is fitted into guide bush to displace therein in and spring-loaded by said bush. Said guide bush is arranged above seat and valve. Aforesaid push rod is spring loaded upward. Note here that valve displaces downward to get in tight interaction with seat. Valve is provided with annular recess. Valve body is furnished with lock to interact with valve anular recess to lock the valve in bottom position.

EFFECT: push rod top provided with springs top with diameter to allow overcoming spring force to displace valve downward at preset pumped fluid flow rate.

2 dwg