Method and apparatus for installing and removing gas lift valves in a well

Claim 2

The combination gas lift valve and shutoff valve adapted to be installed into a tubing string comprising, a valve body, an inlet into said valve body, a shutoff valve means including means urging said shutoff valve means toward open position connected to said inlet and responsive to fluid pressuRe at said inlet, a pressure responsive gas lift valve, fluid communication means through said valve body connecting the outlet from said shutoff valve means to the inlet of said gas lift valve, an outlet extending through said valve body in communication with the outlet of said gas lift valve, and a pair of sealing elements positioned around said valve body for sealing engagement with the interior of the tubing string in which said combination valve is positioned, said sealing elements being positioned immediately above and below said inlet into said valve body.

Claim 3

A mandrel for receiving a gas lift valve comprising, a mandrel body, a pair of passageways through said mandrel body, means at each end of said passageways for connection of tubing thereto, means in one of said passageways for selectively seating a gas lift valve, communication means through said mandrel body between the interior of said one passageway and the exterior of said mandrel body, and means responsive to a pressure differential between said other passageway and exterior of said mandrel closing and opening said communication means.

Claim 4

A mandrel for receiving a gas lift valve comprising, a mandrel body, a pair of passageways through said mandrel body, means at each end of said passageways for connection of tubing thereto, means in one of said passageways for selectively seating a gas lift valve, communication means through said mandrel body between the interior of said one passageway and the exterior of said mandrel body, and means responsive to a pressure differential between said other passageway and exterior of said mandrel closing and opening said communication means.

Claim 5

A mandrel according to claim 2 including, spaced annular surfaces in said passageway for engagement with seals carried by a gas lift valve, and a bypass passageway through said mandrel body and communicating with said passageway above and below said spaced annular surfaces.

Claim 6

A mandrel according to claim 2 wherein said means closing and opening said communication means comprises a cylinder within said mandrel body interposed in said communication means and a spool valve movably positioned in said cylinder to open and close said communication means.

Claim 7

A combination mandrel and gas lift valve comprising, a mandrel body, said mandrel body having a passageway extending therethrough, a gas lift valve having a body adapted to selectively seat in said passageway in said mandrel body, communication means through said mandrel body between the interior of said passageway and the exterior of said mandrel body, and valve means positioned in said mandrel body in said communication means and closing said communication means in response to a selected high-pressure external of the mandrel body.

Claim 8

A combination mandrel and gas lift valve comprising, a mandrel body, said mandrel body having a passageway extending therethrough, a gas lift valve having a body adapted to selectively seat in said passageway in said mandrel body, communication means through said mandrel body between the interior of said passageway and the exterior of said mandrel body, and valve means positioned in said mandrel body in said communication means and closing said communication means in response to a selected high-pressure external of the mandrel body.

Claim 9

A combination tubing mandrel and valve comprising, a mandrel body, said mandrel body having a passageway extending therethrough, a valve having a body adapted to selectively seat in said passageway in said mandrel body, communication means through said mandrel body between said passageway and the exterior of said mandrel, said valve body positioned in said mandrel passageway, a first pressure responsive valve means in said valve body, a second valve means in said valve body, said first valve means adapted to close said communication means between said mandrel body and said second valve means in response to a selected high-pressure external of said mandrel and to open said communication means when pressure external of said mandrel is less than said selected high pressure, said second valve means adapted to open and close said communication means at a position between said first valve means and said passageway through said mandrel body, said first and second valve means positioned in said communication means whereby closure of one of said valve means will close said communication means.

Claim 10

A combination tubing mandrel and valve comprising, a mandrel body, said mandrel body having a passageway extending therethrough, a valve having a body adapted to selectively seat in said passageway in said mandrel body, communication means through said mandrel body between said passageway and the exterior of said mandrel, said valve body positioned in said mandrel passageway, a first pressure responsive valve means in said valve body, a second valve means in said valve body, said first valve means adapted to close said communication means between said mandrel body and said second valve means in response to a selected high-pressure external of said mandrel and to open said communication means when pressure external of said mandrel is less than said selected high pressure, said second valve means adapted to open and close said communication means at a position between said first valve means and said passageway through said mandrel body, said first and second valve means positioned in said communication means whereby closure of one of said valve means will close said communication means.

Claim 11

A mandrel for receiving a gas lift valve comprising, a mandrel body, a passageway through said mandrel body, means at each end of said passageway for connection of tubing thereto, means in said passageway for selectively seating a gas lift valve, communication means through said mandrel body between the interior of said passageway and the exterior of said mandrel body, means closing and opening said communication means, spaced annular surfaces in said passageway for engagement with seals carried by a gas lifT valve, and a bypass passageway through said mandrel body and communicating with said passageway above and below said spaced annular surfaces.

Claim 12

A mandrel for receiving a gas lift valve comprising, a mandrel body, a passageway through said mandrel body, means at each end of said passageway for connection of tubing thereto, means in said passageway for selectively seating a gas lift valve, communication means through said mandrel body between the interior of said passageway and the exterior of said mandrel body, means closing and opening said communication means, spaced annular surfaces in said passageway for engagement with seals carried by a gas lifT valve, and a bypass passageway through said mandrel body and communicating with said passageway above and below said spaced annular surfaces.