Patent ID: 9297234
Filing Date: 2016-03-29
CPC Classification: E21B

Claim Text:
1. A well control apparatus, for controlling back flow out of a tubing string in a well, the well control apparatus comprising: a tubular well including an outer surface, an inner bore and a port through the tubular wall providing communication when open between the outer surface and the inner bore; a slideable sleeve valve in the inner bore, the slideable sleeve valve axially moveable from a closed position overlying the port to an open position retracted from the port, the slidable sleeve valve includes an upper end, a lower end and an inner wall with an annular recess, the annular recess including a first diameter region adjacent the upper end and a smaller diameter region between the first diameter region and the lower end; an inner sleeve including a first end, an opposite end, a collet at the first end and a seat at the opposite end, the inner sleeve being positioned in the annular recess and moveable axially along the annular recess between an upper position wherein the collet resides in the first diameter region and a lower position wherein the collet resides in the smaller diameter region; a first plug for moving the inner sleeve to form the constriction and for sealing against back flow in the well, the first plug sized to pass through the collet when the inner sleeve is in the inactive upper position and to land in the seat to drive the inner sleeve from the upper position to the lower position, thereby to reconfigure the collet to form the constriction, and the first plug being moveable and sized to flow back and create a seal against the lower seat of the constriction; and a second plug for opening a bypass around the seal, the second plug sized to be stopped in the upper seat and to apply a force to move the slideable sleeve valve to the open position, to thereby provide a bypass around the seal.