Abstract: A wet connection system comprises a fixed tubing with an orientation profile and redundant, first and second fixed wet connectors, and an electrical submersible pump assembly (ESP) comprising a wet connector and an orientation element for engaging the orientation profile. The ESP can be reconfigured, for example, by interchanging its component modules so as to change the position of its wet connector with respect to the orientation element, whereby the wet connector on the ESP can be engaged alternatively with either one of the fixed wet connectors when the orientation element is engaged with the orientation profile in the same deployed position of the ESP.

Abstract: A Deployment of fibre optic cables and joining of tubing for use in boreholes. A self supporting fibre optic cable (2, 14?) is slidingly deployed in a borehole via a small diameter conduit (1, 2?) which may be perforated to enable distributed sensing over at least part of the length of the cable. The cable may comprise a casing made from plural concentric tubular steel layers with aligned perforations. In another embodiment, a cable is deployed via wellhead valving and suspended from a fixture comprising a pulley assembly located beneath the valving. The pulley assembly takes up slack in the cable when the upper end of the cable is released, allowing the cable to fall through the valving so that the valving can be closed. The upper end of the cable includes a termination which is located by the fixture so that it can be retrieved. In an other embodiment, two concentric tubing portions are joined by forming dimples in the inner tubing portion which extend into holes the outer tubing portion.

Abstract: An ESP is suspended downhole on a cable comprising spirally wound copper clad steel conductors surrounded by nonmetallic sheathing wound in an opposite spiral direction, preferably in the direction of rotation of the rotor of the ESP. The torque exerted on the cable by the ESP is reacted against the conductors, relieving stress from the sheathing so that the cable may be light in weight yet support substantial loads.

Abstract: An electrical connection for use in boreholes or other remote environment has first and second conductive members. The two conductive members are movable to form an electrical contact. Also provided is a means for urging dielectric fluid around the electrical contact formed by the first conductive member and second conductive member as the first and second conducting members are moved together.

Abstract: A synchronous permanent magnet motor is controlled independently of position sensing means by determining the system parameters including the motor impedance and back-emf and the cable impedance and supplying power according to a predefined voltage:frequency ratio which is determined based on said system parameters to provide a desired rate of acceleration determined by the supply voltage.

Abstract: An electric pump assembly is provided in a well, the pump comprising an electric motor module having a first outer housing and a first mating means, an electric pump module having a pump inlet and a pump outlet, and a second outer housing and a second mating means. In one aspect, the electric motor module and electric pump module are capable of being reversibly joined together by the first and second mating means, as the electric motor module includes a first rotating member that is capable of rotating relative to the first outer housing, and the electric pump module includes a second rotating member that is capable of rotating relative to the second outer housing. In this way, the first rotating member and second rotating member can transfer torque when the electric motor module and electric pump module are joined. In another aspect, a flowpath is provided in each module, the flowpaths fluidly communicating when the modules are joined.

Abstract: A sensor system for use in a wellbore has a fiber-optic cable and a tool connected to the cable and moveable through the well bore. The tool in turn has an array of members arranged around a circumference of the tool and extending radially outwardly to contact an inner surface of the wellbore or a tube in the wellbore, and an array of Bragg grating fiber-optic sensors each configured such that movement of a respective sensing element results in a measurable value or change in the respective sensor. The sensors are arranged to sense a common physical parameter to be measured at a plurality of discrete positions around a circumference of the wellbore or the tube in the wellbore.

Abstract: A drive means for downhole use comprises an input shaft and an output shaft, the input shaft being coupled to a means of rotation, the input shaft and the output shaft being torsionally coupled, the output shaft being coupled to the rotor of the progressive cavity pump, the input shaft lies in a first axis and the output shaft lies in a second axis, the second axis being parallel to the first axis but spaced from it so that the output shaft rotates about its axis while describing a circular path.

Abstract: According to the present invention, there is provided a well pumping system comprising a length of coiled tubing extending to the surface of the well, a first electric pump, a first electric motor, and a sealing means that seals against the side of the well. The sealing means include a first fluid path through which coiled tubing is in fluid communication with the well beneath the sealing means, and a second fluid path through which first electric pump is in fluid communication with the well beneath the sealing means.

Abstract: According to the present invention, there is provided a system for installing a powered device in a downhole tube, the system comprising a power line disposed along a production tube and terminating in a first power connector and an orientation profile disposed in the vicinity of the first power connector. An assembly includes a powered device having a second power connector and an extending orientation means capable of radial outward movement from the assembly. The powered device being lowered down the production tube, causing the extending orientation means to be urged radially outwards to engage with the orientation profile and orient the device, so that the first power connector means and second power connector means engage to connect the powered device to the power line in an automatic manner.

Abstract: According to the present invention, there is provided a sub surface safety valve in a well system comprising an upper support means, a sub surface safety valve, a sealing means that seals against the inside of the production path and a bore through the sub surface safety valve and sealing means which connects to an annular inlet beneath the sealing means and an annular outlet above the sub surface safety valve.

Abstract: A pump system for use in with a downhole pipe string has a pump comprising at least one cylinder with at least one piston inside the cylinder, the movement of the piston causing fluid to be drawn into the pump through a pump inlet before being pushed out through a pump outlet. The pump is housed in a tube having a cammed surface formed by internal wall of the tube, and the piston has a cam follower such that rotation of the piston relative to the tube causes the piston to move relative to the cylinder. Further, a pump system is shown which has two or more such pumps arranged along the downhole pipe string, the pump outlets feeding into a common manifold. The strokes of the piston or pistons of one pump may be out of step with the strokes of the piston or pistons of another pump such that the outlet stream is more uniform.

Abstract: A flow restrictor for controlling the flow of cement or other fluid in oil wells comprises a plurality of restrictor elements, each defining first and second apertures, which are assembled in a stacked configuration and slidingly inserted into the well casing or other tubing so that the first apertures define a direct flowpath, preferably including a non-return valve, and the second apertures define a second, indirect flowpath between the elements and the inner surface of the tubing. The elements include seals for fluidly sealing each element in the bore of the tubing which are preferably slidably retractable and resiliently radially outwardly biased so as to adapt conformably to different tubing types having different internal diameters. The restrictor may slide along the tubing in use.

Abstract: An electrical connection for use in boreholes or other remote environment has a a first connection assembly having a first (18) and second (34) connection assemblies having a first and second conductive members. The two conductive members are movable to form an electrical contact. Also provided is a means for urging dielectric fluid around the electrical contact formed by the first conductive member and second conductive member as the first and second conducting members are moved together.

Abstract: An electric submersible pump assembly (ESP) (21, 120) is deployed in a production tube (20, 100) in a borehole such that the motor (26, 41, 121) of the ESP is spaced from the inner wall of the production tube, defining a conduit (36, 111) through which the pumped well fluid can flow to cool the motor. The production tube may have an enlarged diameter portion (25, 76, 101) within which the motor is positioned. Alternatively or additionally, the ESP and/or the production tube may be provided with stabilising spacers (24, 45, 140, 141) which extend between the ESP and the tube to centralise the ESP in the tube and support it against vibrational movement, the spacers defining an annular conduit (36, 111) between the motor casing and the production tube.

Abstract: A sensor system for use in a well bore includes a metal-clad fiber-optic cable, the fiber optic cable include one or more Bragg gratings, and each Bragg grating is configured such that a value or change in a physical parameter to be measured results in a measurable value or change in the Bragg grating. The sensor system is included in a tool moveable through a drill string. The Bragg gratings are subjected to a strain related to the well bore's pressure, such that the pressure can be determined from the characteristics of the Bragg grating.

Abstract: A method of developing software capable of performing a task, the task comprising at least one task step required to perform the task. The task step has a resultant effect. The method comprises recording a use case comprising one or more scenarios, that comprise one of more further steps; recording the scenario or one of the scenarios as a main success scenarios such that the resultant effect of the main success scenario is the same as the resultant effect of the task step. Use cases which have been stripped of context-specific information may be re-used. Such information may be included in a reference to the re-used use case.

Abstract: A cable and coiled tubing suspends an electrically powered tool in a borehole and providing the tool with electrical power by the cable, the cable being disposed in the coiled tubing, the cable incorporating a conducting member which carries the majority of the tensile stress on the cable, and without the cable being secured along its length to the inside of the coiled tubing. The cable may be capable of supplying high voltage electrical power, in which case the cable comprises a conducting member having a steel core, an outer cladding of copper, and at least one insulating layer surrounding the outer cladding of copper, the copper making up between 20% and 40% of the total copper and steel content of the cable, the cable being able to support at least its own weight.

Abstract: A wet connection system suitable for use in hydrocarbon wells preferably comprises one or more elongate, small diameter conduits (50) which extend down the wellbore (2) and terminate adjacent a locating structure (11) on the production tubing (10). Equipment (70) deployed at the locating structure is connected to one or more self supporting conductors (30) which extend down the conduits from the wellhead (5). Preferably the conductors are retractable and the conduits are sealingly connected to the equipment, allowing the equipment and conductors to be deployed and recovered independently of each other and to be flushed with dielectric oil (99) pumped down the conduits after re-connection.

Abstract: A seal assembly (10?; 30?) comprises a plurality of deformable annular seals (10; 30), each having an annular recess (17) at one end, which are inserted one by one in a relaxed condition in coaxial stacked relation into an annular bore (54) and then compressed axially one by one so that an insert body (16; 32) enters into the recess in each seal, radially energising it. The insert body may comprise an opposite end (16) of the adjacent seal, or a body (32) of fluid or gel. The inner wall of each seal comprises a sealing surface and at least one sealing bead protruding radially inwardly from the sealing surface; the sealing surface limits the depth to which the bead can penetrate the casing of the cable.