摘要:
A mechanism for selectively activating a plurality of downhole pathways including a) a valve having: i) a sleeve coupled for movement between an open and normally closed position; and ii) a valve magnet set mounted to the sleeve; and b) a dart for pumping in hole including a dart magnet set matched to the valve magnet set such that the dart couples to the valve when in close proximity and, in turn, the sleeve moves from the closed position to the open position.
摘要:
A mechanism for selectively activating a plurality of downhole pathways including a) a valve having: i) a sleeve coupled for movement between an open and normally closed position; and ii) a valve magnet set mounted to the sleeve; and b) a dart for pumping in hole including a dart magnet set matched to the valve magnet set such that the dart couples to the valve when in close proximity and, in turn, the sleeve moves from the closed position to the open position.
摘要:
Techniques for axial vibration control of wireline tools and cables during logging operations. In undesirable cases the axial vibrations may lead to or exasperate the stick-slip problems of the logging tool. Control systems and strategies to minimize vibrations and techniques for identifying and inhibiting the sticking of the cable. A system includes a surface actuator and a sensor. The actuator generates an axial wave on the wireline cable which travels down the cable. If there is sticking of the cable, a reflection can also occur at the location of sticking. This shift in the transmission of the wave on the wireline cable is used to identify the onset and/or presence of sticking.
摘要:
The subject disclosure relates to energy harvesting. More particularly, the subject disclosure relates to harvesting energy from the relative motion between a rotary stabilizer and the drill string. In further embodiments, the subject disclosure relates to harvesting energy from vibrations in the drill string.
摘要:
A logging tool having a tool body, which can be positioned in a fluid-filled borehole, including a receiver section and a dipole transmitter; wherein the dipole transmitter includes a transducer with a shell having a reaction mass and a motor located therein, the motor operatively connecting the shell and the reaction mass such that only an outer surface of the shell is in contact with the fluid in the borehole. This new type of dipole source for well logging involves shaking all or part (axially) of a dipole tool body to produce a pure, broadband acoustic dipole signal while at the same time coupling as little energy as possible into the tool body. Important variations on this idea include a linear phased array of shaker sources, and active cancellation of tool borne noise.
摘要:
A downhole tool, having a central axis defined, may selectively include a sensor section including one or more arms connected to the tool body with an open/close mechanism. The open/close mechanism is configured to move in a radial direction with respect to the axis of the tool body. The tool also includes at least one sensor attached to the arm, and the tool may include at least one transmitter section on the tool. The transmitter is configured to transmit acoustic energy to a formation.
摘要:
A formation logging tool having a substantially continuous central mandrel with regularly spaced mass blocks disposed thereon, at least some of the mass blocks carrying sensors such as receivers. By adopting this structure, the tool can be made to behave as a mass-spring structure and its flexural and extensional behaviour controlled such that its dispersion curve does not extend into the dispersion curve of the formation to be logged. The structure can be applied to the whole of the logging tool or just to the receiver section and/or any spacer section between the receiver and the transmitter section.
摘要:
A sleeve for an acoustic logging tool has a structure with a window section having fewer bars than a conventional sleeve separated by a slotted region with thin circumferential slots which are stress-relieved at the ends (“dumb-bell” shaped). Steel receiver mounts are provided for hydrophone pressure sensors and this, together with the axially oriented hydrophones makes the tool less susceptible to interfering vibration.
摘要:
A sleeve for an acoustic logging tool having a structure with a window section having fewer bars than a conventional sleeve separated by a slotted region with thin circumferential slots which are stress-relieved at the ends (“dumb-bell” shaped). Steel receiver mounts are provided for hydrophone pressure sensors and this, together with the axially oriented hydrophones, makes the tool less susceptible to interfering vibration.
摘要:
An apparatus for deploying an instrument usable with a well comprises at least one reversibly expandable structure, at least one actuator operable to change a perimeter dimension of the at least one reversibly expandable structure, at least one instrument disposed interior of the at least one reversibly expandable structure, and having an axial dimension, and tractoring fluid disposed between the at least one reversibly expandable structure and the at least one instrument. The apparatus is operable to perform at least one of exerting thrust to convey the at least one instrument with respect to at least one adjacent surface, creating compensating pressure between the at least one instrument and the at least one adjacent surface, and sealing between the at least one instrument and the at least one adjacent surface.