BORE-HOLE DISCONNECTOR Russian patent published in 2011 - IPC E21B17/06 

FIELD: oil and gas industry.

SUBSTANCE: bore-hole disconnector includes hollow disconnected reducer with thread at the top and collet at the bottom and sleeve with thread at the bottom and annular recess for collet on the outer side. Sleeve has many-sided projections on the outer side at the top, which are connected by means of collet equipped from the inside with many-sided slot for many-sided slots of sleeve and movable sleeve fixed on the outside. Movable sleeve is installed on reducer with possibility of tight longitudinal upward movement under action of excess pressure in cylindrical cavity interconnected through a hole to reducer cavity. Cylindrical cavity is formed with lower annular extension of reducer and upper annular narrowing of movable sleeve, which envelops annular extension of reducer with possibility of tight upward movement. Annular narrowing for free-fall ball is made in the cavity below reducer holes. Side channel is made in movable sleeve and has the possibility of interaction with cylindrical cavity at upward movement of movable sleeve. Reducer can be equipped from above with rigid centraliser.

EFFECT: reliability is ensured irrespective of pressure drop with possibility of control of actuation from well head, and jamming of device is excluded at its actuation in well.

2 cl, 2 dwg