Schlumberger Technology Corporation

Anthony P Vovers

Dinesh R Patel

Gary L Rytlewski

James E Brooks

Lawrence A Behrmann

Robert A Parrott

Vladimir Vaynshteyn

Ian C Walton

Laurent E Muller

Vance E Nixon

Haoming Li

Christopher W Spiers

Adinathan Venkitaraman

Cynthia L Hickson

Ashley B Johnson

John M Corben

Michael W Fruge

Harry B Anderson

A tool that is usable in a subterranean well to sample well fluid from a zone does not include a pump to remove well fluid from the zone for purposes of sampling. Instead, the tool includes a flow path that is in communication with the zone and a region of the well above the zone to use a pressure differential created or naturally occurring between the zone and the region of the well above the zone to flow well fluid from the zone. The tool may also include a flow path that is in communication with the region of the well above the zone and the region of the well below the zone to equalize pressure along the tool and thereby prevent unintended axial movement of the tool. A fluid sampler of the tool samples a composition of the well fluid from the zone.

Slimhole fluid tester

A method and apparatus for improving reservoir communication includes, in one arrangement, use of one or more chambers to create an underbalance condition and/or a fluid surge in the wellbore. In another arrangement, a tool string comprises a packer, a circulating valve, and an atmospheric chamber, in which the circulating valve, when open, is adapted to vent a lower wellbore region below the packer when the packer is set, and the atmospheric chamber is capable of being operated to create an underbalance condition below the packer. In yet another arrangement, an apparatus comprises a subsea wellhead equipment including a blow-out preventer, choke line filled with a low density fluid, and a kill line filled with a heavy fluid. The choke line is adapted to be opened to create an underbalance condition in the wellbore. In yet another arrangement, a method of creating an underbalance condition comprises controlling wellbore pressure at least in a perforating interval to achieve a target level, configuring a perforating gun to achieve a target detonation pressure in the perforating gun upon detonation, and creating an underbalance condition in the perforating interval of the wellbore when the perforating gun is shot. In yet another arrangement, a tool string for use in a wellbore extending from a well surface comprises a closure member adapted to be positioned below the well surface, and a chamber defined at least in part by the closure member. The tool string further comprises at least a port selectively openable to enable communication between the chamber and a wellbore region. The port when open creates a fluid surging to the chamber to provide a low pressure condition in the wellbore region. A tool in the tool string is adapted to perform an operation in the low pressure condition.

Reservoir communication with a wellbore

A tool string for use in a well includes a filter sub (or trapped pressure regulator sub) that is used with other components to reduce trapped pressure. The filter sub filters out debris that may occur from various types of downhole operations, such as perforating operations. By filtering out larger debris, only gases, liquids, and smaller particles are allowed to enter various components of the tool string. Without the presence of larger solid debris inside certain components of the tool string, the likelihood of plugs being formed is reduced so that gases and liquids can more readily pass out of the tool string as the tool string is retrieved to the surface of the well and the well hydrostatic pressure decreases.

Method and apparatus to reduce trapped pressure in a downhole tool

An apparatus for retaining fluid in a pipe includes an elongated body adapted to be positioned within a subsea wellhead assembly. The elongated body has an end adapted for connection to the pipe, a flow passage for fluid communication with the pipe, and an outer surface for engagement with a sealing member in the subsea wellhead assembly. A first chamber is defined within the elongated body and connected to receive pressure from above the subsea wellhead assembly. A second chamber is defined within the elongated body and connected to receive pressure from below the subsea wellhead assembly. A valve is supported in the elongated body for movement in response to pressure differential between the first and the second chambers. The valve is movable between an open position to permit fluid flow through the flow passage and a closed position to prevent fluid flow through the flow passage.

Retainer valve

A well string for use in a wellbore having plural fluid regions includes a flow conduit having an inner bore defining one of the fluid regions and an actuating assembly including an operator mechanism, an activation port in communication with the operator mechanism, and a member adapted to block the activation port. The member is moveable by an applied pressure in a first fluid region to expose the activation port to a second fluid region. The operator mechanism includes a piston assembly. The first fluid region may include the annulus region outside the flow conduit, and the second fluid region may include the flow conduit inner bore.

Pressure-controlled actuating mechanism

A locking apparatus which includes a rupture disc, prevents a packer from setting while being lowered into a wellbore. When the rupture disc ruptures, the packer can then set. The locking apparatus includes a locking sleeve for holding a locking dog into a locking recess in a mandrel. A drag block is locked to the mandrel as long as the locking dog is held into the locking recess of the mandrel. A packer connected to the mandrel is prevented from setting as long as the drag block is locked to the mandrel. Pressure in an annulus around the locking sleeve increases until it exceeds a predetermined threshold pressure value. When the annulus pressure exceeds the threshold pressure value, a rupture disc in the locking sleeve ruptures thereby allowing the annulus pressure to enter a chamber and move the locking sleeve away from the locking dog. When the locking sleeve moves away from the locking dog, any subsequent longitudinal movement of the mandrel moves the locking dog out of its locking recess. When the locking dog moves out of its locking recess, a sleevlet, connected to the locking dog, moves in the same direction as the locking dog thereby filling the locking recess originally occupied by the locking dog. When the sleevlet fills the locking recess, it is ratcheted in place thereby permanently filling the locking recess. When the locking recess is permanently filled, the lock is permanently removed. Therefore, the mandrel is free to move longitudinally relative to the drag block. As a result, the packer can be either set or unset simply by moving the mandrel longitudinally in the wellbore.

Locking apparatus for locking a packer setting apparatus and preventing

Growing community of inventors

Houston, TX, United States of America

Anthony P Vovers