Abstract:
A connection system for connecting external devices to a streamer. The connection system comprises three outer collars maintained collinearly aligned by a stabilizing member, such as a lightweight, rigid tube, attached to each outer collar. The tube extends parallel to the bores of the outer collars. The forward and aft outer collars ride on races formed on the periphery of inner collars clamped around mounting structure in the interior of the streamer. An external device is attached to the forward collar and to the intermediate collar, which does not ride on an inner collar. The spacing between the forward and intermediate collars is fixed by the standard spacing of the two attachment points in standard external devices. The spacing between the forward and aft collars is set by the specified spacing of mounting structures in the interior of the streamer.
Abstract:
A bend stiffener includes a first elongate member having a longitudinal conduit and a second elongate member also having a longitudinal conduit connected to an end of the first member thereby effectively extending the length of the bend stiffener. The first member has a resilience to bend when the bend stiffener is subject to a certain load, i.e. at a large tension and small angle, while the second member is designed to have less resilience than the first member, whereby the second member starts bending earlier than the first member when the bend stiffener is subjected to a smaller load, i.e. at a low tension and/or a large angle. The first and second members may provide one or more channels from the second member to the hydrophone. The channel surfaces may have a nonmetallic material. The second member has a resilience to transfer incident pressure waves into the channel therein.
Abstract:
A cleaning device for a seismic streamer includes a housing placeable the exterior of the streamer. A turbine is associated with the housing and is configured to be rotationally driven by movement of the streamer through a body of water. A drive element is associated with the housing and is configured to convert rotational motion of the turbine to motive power to move the housing along the streamer. At least one cleaning element is associated with the housing and is cooperatively engaged with the exterior of the seismic streamer. A method for cleaning a streamer includes towing the streamer through the water. Motion of water is converted into motive power to move a cleaning device along the streamer.
Abstract:
A connector for a seismic data acquisition cable includes a molded plastic connector body. The connector body has inserted therein at least one electrical contact for mating with a corresponding electrical contact. The connector body has an internal opening for receiving an electrical cable. The connector body has a mating surface adapted to contact a corresponding connected structure. The internal opening is filled with a curable compound which upon cure forms a substantially interface free bond with the connector body and an external jacket of the electrical cable.
Abstract:
A robust seismic cable and sensor module system wherein the sensor modules include a housing and sensing unit. The housing substantially transfers the load and torque of the cable from one end of the housing to the other bypassing the sensing unit and the sensing unit and housing are acoustically decoupled from each other for the seismic frequencies desired.
Abstract:
A seismic streamer includes a jacket covering an exterior of the streamer. At least one strength member extends along the length of and disposed inside the jacket. At least one seismic sensor is mounted in a housing affixed to the at least one strength member. A void filling material fills the interstices inside the jacket. The housing is configured to isolate the at least one sensor from pressure variations in the void filling material, and the housing is configured to couple the at least one sensor to a body of water outside the streamer.
Abstract:
Disclosed are electric cables with improved armor wires used with wellbore devices to analyze geologic formations adjacent a wellbore. The cables include at least one insulated conductor, and one or more armor wires surrounding the insulated conductor. The armor wires include a low density core surrounded by a corrosion resistant alloy clad, where the alloy clad includes such alloys as beryllium-copper based alloys, nickel-chromium based alloys, superaustenitic stainless steel alloys, nickel-cobalt based alloys, nickel-molybdenum-chromium based alloys, and the like. The low density core may be based upon titanium or titanium alloys. The cables of the invention may be any useful electric cable design, including monocables, quadcables, heptacables, quadcables, slickline cables, multiline cables, coaxial cables, or seismic cables.
Abstract:
A method for wrapping continuous strands of steel wire about a seismic cable including interconnected sensor sections and conductor sections where a cross sectional diameter of the sensor section is at least four times that of the conductor section. Two layers of armoring are provided with a first layer wrapped in a first angular direction opposite that of the second layer. A stranding assembly is provided which has two selective positions, one for providing a die hole for stranding the conductor section, another for providing a passage hole for allowing the sensor section to pass after wrapping with armor wire.
Abstract:
The present invention provides an underwater cable arrangement includes an underwater cable having one or more external devices mounted on the cable. In one form of the invention, the external devices are powered primarily or entirely by inductive coupling between a coil disposed in the cable and a coil disposed in the external device. The invention also provides a variety of external devices capable of use with an underwater cable. The invention further provides a coil support arrangement for supporting a coil within an underwater cable in a manner protecting a core of the coil from damage.
Abstract:
A pressure-sensitive switch comprising an electrically-insulating base member having front and back surfaces with a through opening extending between the two at the center of the base member. Two electrodes are mounted on the base member's front surface and each have an electrically-conductive contact surface. A flexible diaphragm has its periphery secured in a fluid-tight manner to the back surface of the base member and is provided with a post connected to the central portion of the diaphragm. The post extends through the base member where an electrically-conductive washer is fixed to it where it extends beyond the front surface of the base member. A fluid-tight cap is secured to the front surface, covering an area above the washer and preventing fluid from entering the switch mechanism. The diaphragm, which is formed with plural corrugations, is exposed to the external pressure. When the switch is exposed to atmospheric pressure, the washer connects the electrodes, but when the switch is exposed to a super-atmospheric pressure, the central portion of the diaphragm pushes the washer out of contact with both electrodes, thus electrically disconnecting the two electrodes. The pressure-sensitive switch is especially useful with hydrophones, as in seismic streamer cables.