Western Atlas International, Inc.

Shaw Industries, Inc.

Litton Resources Systems, Inc.

Other

Sercel, U.S. Inc.

James A Sackett

William O McNeel

Joe N Wood

Roger M Logan

Julian Soliz, Iii

A method of and an apparatus for mounting seismic vibration sensors to a cable designed for use offshore, such that the sensors are optimally coupled to the ocean floor through all cylindrical rotations when the cable has reached the bottom after being slipped over the transom of a deployment vessel. Said coupling is accomplished without the use of a sub-surface robotic vessel to force the sensors into a particular orientation. The housing for the sensors is adapted to endure and minimize the impact on the host cable of the mechanical extremes the system is subjected to in the process of the conventional deployment and retrieval methods.

Seismic sensor shroud package

A high frequency shielded data transmission cable and method of making same are disclosed. Optimal transmission and minimal signal loss are achieved when the conductors of such a cable are maintained in fixed positions relative to one another and relative to the metal shielding. These features are provided by a cable of the instant invention wherein a central core having diametrically opposed spiral grooves hold the insulated conductors in fixed relation to one another. At least one inner layer of dielectric material maintains the insulated conductors within the grooves and provides a fixed spacing between the conductors and the metal shielding. Metal shielding, preferably of braided strips of metal, provides additional strength and flexibility to the cable. The interstitial spaces of the braid may optionally be filled with a filling compound. Likewise, the insulated conductors may be coated with a water-blocking compound to fill any spaces between the conductors and the walls of the grooves. The cable of this invention is suitable for use in harsh environments such as ocean bottom applications where it may be subjected to high pressure and substantial bending. The use of the novel central core of this cable prevents relative lateral movement of the conductors and reduces the volume of interstitial space that might otherwise collapse under such extreme conditions. In addition, a cable of this invention will allow longitudinal movement of the insulated conductors within the grooves thereby allowing the stress and compressive forces that would otherwise fatigue a cable to be relieved.

Twin axial electrical cable

A waterproof splice for use in connecting two multiconductor electric cables having jackets of different insulation material and a method of making the splice are disclosed. The splice consists of a mechanical electrical connection between the conductors, a mechanical bond formed on the insulation of one of the conductors and a sheath of insulation material molded over the splice and adjacent cables. The sheath bonds with the jacket of one cable and the mechanical bond formed on the insulation of the other cable. The mechanical bond is a seal ring of elastomeric material that is compressed between glands to move the seal ring into sealing engagement with the conductor. The disclosed splice is both strong and waterproof in spite of the poor bonding characteristics between the two different insulation materials on the two conductors. The splice is appropriate for cables having surface, subsurface and underwater applications and is specifically designed for use in conducting seismic surveying operations.

Waterproof splice for cables having different insulation materials and

Doping the jacket of a data cable reduces the bulk volume resistivity of the jacket material allowing built-up static electricity to discharge. This reduces the likelihood of static charge interfering with data transmission.

Static dissipating data cable and seismic apparatus

A twin-axial cable comprises a central core around which two conductors are helically wrapped. Interspersing a plurality of spacers between the conductors determines the relative placement of the two conductors on the core. A dielectric barrier encases the core, conductors, and spacers.

Electrical cable

A spring for a seismometer for suspending one body relative to a fixed reference point within a housing including an outer ring and an inner ring interconnected by a plurality of arcuate legs. Each leg has an inner and an outer edge which may be defined by a plurality of arcs of different radii and distinct centers. The plurality of arcs further divide each leg into an inner section and an outer section of approximately equal length, and a middle section of substantially constant width and thickness. The spring provides an improved spurious resonance over the prior art springs as well as having an improved useful life.

Geophone spring

A boatlift including two floatation chambers operably engaged to a boat hull engaging means by a lifting means connected therebetween. The lifting means is adapted to raise and lower the boat hull engaging means with respect to the floatation chambers, which, in turn, is adapted to buoyantly support both the boat hull engaging means and the lifting means. The boat lift may be either connectable to a stationary object such as a dock, pier or seawall, or may be adapted to be trailerable by land vehicle.

Shallowdraft floating boatlift

A transducer assembly for use along the surface of the earth or in a borehole to detect seismic signals along mutually orthogonal axes. The transducer assembly includes at least two geophones or accelerometers gimbally-mounted within a housing such that when the housing is oriented at substantially any angle, the enclosed geophones remain in their respective planes with respect to gravity and their axes of sensitivity to the seismic signals remain orthogonal to each other.

Three-axis sensor

The compound accelerometer is made by combining two simple accelerometer units. The simple accelerometer units consist of a hollow container closed at each end by a piezo-electric transducer. The two transducers are oppositely polarized and are selected to have a desired combined series capacitance value. The container is partially filled with a volume of heavy liquid and the accelerometer is excited. During excitation, the output voltage is continuously measured and the volume of liquid is microadjusted until the output voltage equals a prescribed level. The outputs of the individual transducers are measured, the residual voltage difference is tabulated and the dominant transducer is identified. Two simple accelerometer units having the same residual voltage difference are secured together with the dominant transducers facing oppositely with respect to each other.

Compound piezoelectric accelerometer with residual voltage matching

A method for manufacturing a compound accelerometer that is maximally sensitive to a desired acceleration vector to the exclusion of orthogonal vectors. The compound accelerometer is made by combining two simple accelerometer units. The simple accelerometer units consist of a hollow container closed at each end by a piezo-electric transducer. The two transducers are oppositely polarized and are selected to have a desired combined series capacitance value. The container is partially filled with a volume of heavy liquid and the accelerometer is excited. During excitation, the output voltage is continuously measured and the volume of liquid is microadjusted until the output voltage equals a prescribed level. The outputs of the individual transducers are measured, the residual voltage difference is tabulated and the dominant transducer is identified. Two simple accelerometer units having the same residual voltage difference are secured together with the dominant transducers facing oppositely with respect to each other.

Growing community of inventors

Houston, TX, United States of America

James A Sackett