Abstract: A Heave-Restrained Platform and Drilling System (HRP/DS) comprises a floating structure having a central buoyance means, at least three out-rigger columns, and a hybrid mooring system in which a spread (lateral) mooring system functions with an array of tensioned production risers (serving as a vertical tension leg) to keep the structure generally over a specified seabed location. The central buoyancy means has supports for upper terminations of a plurality of well production risers. Each riser is comprised of plural concentric tubular structural and pressure containment elements connecting a hydrocarbon well on the sea floor with a pressure containment means located on the floating structure.

Abstract: An apparatus and method are provided for dewatering an interior of a hollow tension leg connecting a tension leg platform to a floor of a body of water. The apparatus includes a pump having a suction inlet defined on its lower end and a discharge outlet on its upper end. An elongated storage tank is attached to the upper end of the pump above the pump and has a tank interior communicated with the discharge outlet. The assembly is lowered on an electric wireline through which power is conducted to the pump. The pump fills the tank and then the assembly is withdrawn from the tension leg and the water is drained therefrom. The assembly can be repeatedly lowered into the tension leg and withdrawn therefrom until the tension leg is substantially completely dewatered. Solid debris can be removed from the tension leg prior to dewatering.

Abstract: A Heave-Restrained Platform and Drilling System (HRP/DS) comprises a floating structure having a central buoyancy means, at least three out-rigger columns, and a hybrid mooring system in which a spread (lateral) mooring system functions with an array of tensioned production risers (serving as a vertical tension leg) to keep the structure generally over a specified seabed location. The HRP/DS provides a means for drilling and producing through oil wells in deep water such that critical pressure containment means are achieved with safe, redundant barriers and systems similar to those employed on shallow water fixed platforms.

Abstract: A data transmission system for use with such as the seven conductor logging cable that functions to provide more precise transmission of data signal with reduced interference from higher powered electrical signals present along the line. The data signals are modulated on a radio frequency carrier which is then inductively coupled to the cable jacket or shielding sheath for conduction along the cable. Thus, as the logging cable supports a downhole tool in a borehole, transmitter/receiver combinations both downhole and at the surface can communicate via modulated RF signal conducted along the standard shielding material of the cable. A primary advantage to this type of transmission is the fact that no signal must reverberate through the cable reel as it can be inductively picked off prior to the cable entering the reel section, resulting in much reduced attenuation and interference.

Abstract: A flow cell for use in highly corrosive environments is constructed from an extended metal body containing a smooth longitudinal circular center bore of uniform cross-section. The metal body contains a circular opening at each end extending perpendicularly into the center bore, adapted to receive a sample into the center bore and discharge the sample from the center bore. A circular connector having a larger diameter than the center bore is contained in each of the opposing ends of the center bore, abutting the solid body to form a right angle shoulder between the inside of the connector and the solid body.

Abstract: A sensor system comprises a fibe optic cable, or a fiber optic cable covered with a cladding, coated with a membrane that is sensitive to a particular substance to be detected. Contact with the material to be detected causes the membrane's index of refraction (normally less than that of the fiber core) to increase, decreasing the intensity of the light transmitted by the core. The fiber-optic sensor can be used to monitor one or more storage tanks for leakage by placing the fiber cable beneath the surface surrounding the tank(s).

Abstract: A tension leg platform which can be a heave restrained platform and drilling system (HRP/DS) is taken to the heave restrained mode by rapidly sluicing ballast by gravitational force from a reservoir above the water line.

Abstract: A tubular plastic liner having a coefficient of thermal expansion greater than the coefficient of thermal expansion of a pipeline is cooled to reduce its outside diameter below the inside diameter of the pipeline, which is also cooled, and is then pulled into the pipeline. After the pulling operation is completed the liner and pipeline are allowed to return to normal temperature, whereupon the liner expands to conform to the inside diameter of the pipeline.

Abstract: A mixture of cyanide complexes with certain Group VIII metals and other metals is passed in contact with solid subdivided cross-linked polyvinylpyrrolidone whereby the Group VIII metals--platinum, palladium, rhodium and iridium--are preferentially retained on the cross-linked polyvinylpyrrolidone. The retained metals are recovered by ashing or chemical treatment of the cross-linked polyvinylpyrrolidone.

Abstract: A method for removing residual moveout includes sorting the results of common offset depth migration into common image point gathers. A subset of image point gathers are selected for analysis. Each common image point gather is separated vertically into windows, each of which centers on a strong event. For each window, all the offset traces are summed to produce a brute stack trace to be used as an anchor. All offsets are cross-correlated to the anchor to determine how much each trace window should be shifted to sum most constructively with the anchor. A set of dynamic shifts is produced, which when applied, will remove the residual moveouts and produce a truly flat image for stacking. These shifts vary with depth and offset and can be interpolated between the selected image point gathers.

Abstract: A method and apparatus for providing shear waves in a marine environment in which a shear wave source penetrates the surface sediment of a water bottom. The shear wave generating source includes an actuator/reaction mass system mounted inside a structural ring of a housing section. A cross-shaped structure at the top of the apparatus serves as a passive reaction mass and as a moment arm support for reversibly motor driven propellers enclosed in shrouds at the outer ends of the structure. A thruster system provides dynamic positioning. The cross-shaped structure and housing section are connected by a structurally stiff member, such as a vertical tube. Pistons provide actuation against a reaction mass located within the housing structure, and motion of the housing structure generates shear waves which propagate in the subsurface formations.

Abstract: The method and apparatus for providing elliptical polarized shear waves in a marine environment in which a shear wave source penetrates the surface sediment of a water bottom includes dual actuator/reaction mass system mounted inside a structural ring of a conical housing section. A cross shaped structure at the top of the apparatus serves as a passive reaction mass and as a moment arm support for reversibly motor driven propellers enclosed in shrouds at the outer ends of the cross shaped structure. A thruster system provides dynamic positioning. The cross shaped structure and housing section are connected by a structurally stiff member, such as a vertical tube. Pistons provide actuation of two reaction masses located within the housing structure, and the motions of the reaction masses generate shear waves which propagate in the subsurface formations.

Abstract: More uniform premium coke is obtained in a delayed coking process by oxygenating the latter portion of the premium coking feed introduced to the coking drum.

Abstract: Temporary plugs are formed in process flowlines by injecting into the flowlines a plugging material having a freezing point only slightly below the ambient temperature. The plugging material is frozen in place, and a servicing operation is conducted on the flowline. The plugging material is then allowed to thaw or is thawed by applied heat. Linear primary alcohols and normal paraffinic hydrocarbons are preferred plugging materials.

Abstract: A method and apparatus by which fractured rock formations are identified and their orientation may be determined includes two orthogonal motion sensors which are used in conjunction with a downhole orbital vibrator. The downhole vibrator includes a device for orienting the sensors. The output of the sensors is displayed as a lissajou figure. The shape of the figure changes when a subsurface fracture is encountered in the borehole. The apparatus and method identifies fractures rock formations and enables the azimuthal orientation of the fractures to be determined.

Abstract: A vapor tight sampler which is used to visually examine flowing liquid or liquids to determine color, gravity and solids content thereof. The sampler comprises a metal block on which are disposed a plurality of clear cylinders which are covered and gasketed at the top and gasketed to the metal block at the bottom. A pressure release plug is provided in each cover. A header is provided in the block for supplying liquid feed. A separate feed line runs from the header to the bottom of each cylinder. Disposed within each cylinder is an aspirating overflow tube to remove liquid and vapors and prevent overfilling of the cylinders. A vent line is provided in the top of each cylinder. The vent lines and overflow tubes are connected to a drain tank through the metal block. The drain tank provides egress to a separator or drain system and a vent line to the atmosphere. Openings are provided in the block below each cylinder for draining purposes.

Abstract: A shipboard support stand for a marine vibrator of the type having characteristic revolutional shape about the vertical axis and a lower concentric guide ring surface which consists of a support ring of circumfery generally equal to the circumference of the vibrator supported by plural vertical supports above the ship's deck, and which further includes a reduced diameter locating ring secured concentrically and at lower elevation from the support ring such that the vibrator can be supported on the support ring with the vibrator guide ring closely retained within the locating ring to stow the vibrator securely.

Abstract: Terpolymers having enhanced pour point depressant properties are disclosed which comprise (1) an alkyl ester of unsaturated monocarboxylic acid, (2) an olefinically unsaturated homo or heterocyclic-nitrogen compound, and (3) an allyl acrylate or methacrylate or a perfluoroalkyl ethyl acrylate or methacrylate. A process for preparing the terpolymers is additionally disclosed.

Abstract: A method and apparatus are used in the acquisition of data by ground-penetrating radar, wherein the signals thus obtained are input to a pre-amplifier which contains filtering component such as an anti-aliasing filter. The base gain of the system is switch selectable and electronically adjusted to bring the input signal to between one half and full scale on an analog to digital converter input. The converted digital value has a resolution of fifteen bits for processing.

Abstract: A system for cleaning solids contaminated with solvent-soluble contaminants. The system comprises the use of at least two successive cleaning zones, each of which includes a slurry stage and a centrifuge separation stage, wherein the solids to be cleaned and the solvent used for cleaning flow in countercurrent relationship to each other between the successive zones.