Well tubing coupling apparatus

A tubing seal divider for releasably coupling an upper tubing string with a lower tubing string in a well bore comprising:

• a lower tubular body section connectible at a lower end on the upper end of a lower tubing string in a well bore including an annular hydraulic cylinder and an annular locking recess spaced from said hydraulic cylinder, and an annular lock having a locking sleeve movable around said locking recess and an integral annular hydraulic piston movable in said hydraulic cylinder and hydraulic fluid passage means leading to said hydraulic piston for communicating casing annulus pressure on the other side of said piston;
• and an upper body section connectible on the lower end of an upper tubing string and telescopically connectible into said lower body section including an annular locking collet having internal locking bosses insertable into said locking recess of said lower body section, said locking collet being adapted to telescope into said lower body section between said locking recess and said locking sleeve of said annular lock whereby said locking sleeve holds said locking collet in locked condition at one end position and releases said locking collet for removal of said upper body section from said lower body section at an opposite end position of said annular lock said piston being movable hydraulically between end positions for disconnecting and reconnecting said upper tubing string and said lower tubing string.

A tubing seal divider for releasably coupling an upper tubing string with a lower tubing string in a well bore comprising:

• a lower tubular body section connectible at a lower end on the upper end of a lower tubing string in a well bore including an annular hydraulic cylinder and an annular locking recess spaced from said hydraulic cylinder, and an annular lock including locking means movable over said locking recess and an integral annular hydraulic piston movable in said hydraulic cylinder between release and lock positions for disconnecting and reconnecting said upper and said lower tubing strings and hydraulic fluid passage means leading to said piston for communicating casing annulus pressure on one side of said piston and tubing pressure on the other side of said piston;
• and an upper body section connectible on the lower end of an upper tubing string and telescopically connectible into said lower body section to provide a fluid conducting coupling between said upper and lower tubing strings including an annular locking collet having locking bosses engageable in said annular locking recess of said lower body section for releasably holding said upper body section with said lower body section, said locking collet telescoping into said lower body section between said locking recess and said annular lock whereby said annular lock holds said locking collet in locked condition at one end position and releases said locking collet for removal of said upper body section from said lower body section at an opposite end position of said annular lock.

A tubing seal divider for releasably coupling an upper tubing string with a lower tubing string in a well bore comprising:

• a lower tubular housing section connectible at a lower end on the upper end of a lower tubing string including an outer housing sleeve, an inner tubular mandrel concentrically spaced within said housing sleeve defining therebetween a hydraulic fluid pressure chamber, port means in said inner mandrel communicating the bore through said mandrel with said pressure chamber, an external annular locking recess on said inner mandrel spaced from said pressure chamber, an annular piston slidable in said pressure chamber, annular lock means on said piston movable with said piston between a first locking position around said locking rec ess of said inner mandrel and a second release position misaligned from said annular locking recess, and an upper body section connectible at an upper end with the lower end of an upper tubing string and having a tubular housing portion sized to telescope over said inner mandrel of said lower housing section, internal annular seal means in said upper body section tubular housing for sealing between said tubular housing and said inner mandrel of said lower housing section, and an annular locking collet on the lower end of said housing of said upper body section for telescoping into said lower body section between said housing of said lower body section and said inner mandrel of said lower body section, said locking collet having internal locking bosses engageable in said locking recess of said inner mandrel of said lower body section, said locking collet being held in locking engagement with said locking recess when said annular lock of said lower body section is at said first position and being releasable from said locking recess when said annular lock is at said second position said piston being hydraulically movable between said first and second positions for disconnecting and reconnecting said upper and said lower tubing strings.