Hydraulic disconnect

Abstract

A disconnect apparatus includes a lower housing, an upper housing having a collet mechanism configured to couple the upper housing to the lower housing, a retainer sleeve disposed within the upper housing and/or the lower housing, the retainer sleeve configured to move longitudinally within the lower housing and/or the upper housing between a first position and a second position in response to a pressure differential applied across the retainer sleeve; wherein in the first position at least a portion of the retainer sleeve is disposed radially inward of the collet mechanism and in the second position the retainer sleeve is disposed axially above or below the collet mechanism, and a biasing mechanism coupled to an end of the retainer sleeve. A method of disconnecting a tool from a tubular string includes applying a differential pressure across a sleeve and disengaging a collet mechanism with a housing.

What is claimed: 
     
         1 . A disconnect apparatus, comprising:
 a lower housing;   a retainer sleeve disposed within the lower housing and configured to move axially within the lower housing, the retainer sleeve having a seating surface configured to receive an obstruction device;   a spring coupled to the retainer sleeve; and   an upper housing configured to removably engage the lower housing.   
     
     
         2 . The disconnect apparatus of  claim 1 , wherein the upper housing includes a collet mechanism disposed on a lower end thereof. 
     
     
         3 . The disconnect apparatus of  claim 2 , wherein the lower housing includes a circumferential groove formed on an inner surface of the lower housing, the circumferential groove being configured to receive the collet mechanism. 
     
     
         4 . The disconnect apparatus of  claim 3 , wherein the retainer sleeve is configured to be disposed radially inward of the collet mechanism in a first position. 
     
     
         5 . The disconnect apparatus of  claim 3 , wherein the retainer sleeve is configured to be disposed axially below the collet mechanism in a second position. 
     
     
         6 . The disconnect apparatus of  claim 5 , wherein in the second position, the spring is compressed. 
     
     
         7 . The disconnect apparatus of  claim 1 , wherein the upper housing includes a retainer disposed therein configured to engage and retain an obstruction device within, or connected to, the upper housing. 
     
     
         8 . The disconnect apparatus of  claim 7 , wherein the obstruction device is a dart. 
     
     
         9 . The disconnect apparatus of  claim 1 , wherein the lower housing includes a plurality of splines formed on an inner surface of an upper end configured to engage a plurality of splines formed on an outer surface of the upper housing. 
     
     
         10 . The disconnect apparatus of  claim 1 , further comprising a seal disposed radially between the upper housing and the lower housing when the upper housing is connected to the lower housing. 
     
     
         11 . A disconnect apparatus comprising:
 a lower housing;   an upper housing having a collet mechanism configured to couple the upper housing to the lower housing;   a retainer sleeve disposed within at least one of the upper housing or the lower housing, the retainer sleeve configured to move axially within the at least one of the lower housing and upper housing between a first position and a second position in response to a pressure differential applied across the retainer sleeve, wherein in the second position the retainer sleeve is disposed axially below the collet mechanism; and   a biasing mechanism coupled to the retainer sleeve and biasing the retainer sleeve in an axial direction.   
     
     
         12 . The disconnect apparatus of  claim 11 , further comprising a float valve disposed in the retainer sleeve, the float valve operable between an open position and a closed position. 
     
     
         13 . The disconnect apparatus of  claim 11 , wherein the biasing mechanism biases the retainer sleeve into the first position. 
     
     
         14 . A method for operating a hydraulic disconnect device, comprising:
 applying a differential hydraulic pressure across a retainer sleeve of a disconnect apparatus, the disconnect apparatus having an upper housing and a lower housing coupled to the upper housing, the retainer sleeve disposed in at least one of the upper housing or the lower housing, wherein applying the differential hydraulic pressure moves the retainer sleeve from a first position to a second position;   applying a tensile load to the upper housing; and   releasing engagement of a collet mechanism of the upper housing from a retaining groove formed in an inner surface of the lower housing.   
     
     
         15 . The method of  claim 14 , wherein applying the differential pressure across the retainer sleeve includes engaging an obstruction device with the retainer sleeve. 
     
     
         16 . The method of  claim 14 , wherein the applying the differential pressure across the retainer sleeve includes closing a float valve disposed in the retainer sleeve. 
     
     
         17 . The method of  claim 16 , wherein the applying the differential pressure across the retainer sleeve includes flowing a fluid through a central throughbore of the retainer sleeve from a bottom of the disconnect apparatus. 
     
     
         18 . The method of  claim 15 , further comprising engaging at least a portion of the obstruction device in a retainer disposed in the upper housing. 
     
     
         19 . The method of  claim 15 , further comprising coupling the obstruction device with the upper housing and removing the upper housing from the lower housing. 
     
     
         20 . The method of  claim 14 , further comprising recoupling the upper housing with the lower housing, the recoupling including:
 disposing the collet mechanism in the lower housing and engaging a lower end surface of the collet mechanism with an upper end surface of the retainer sleeve;   applying an axial load to the upper housing to move the collet mechanism and the retainer sleeve axial downward;   engaging the collet mechanism with the retaining groove of the lower housing; and   moving the retainer sleeve axial upward until at least a portion of the retainer sleeve is disposed radially inward of the collet mechanism.