Abstract: The present disclosure addressed apparatus and methods for forming an annular isolator in a borehole after installation of production tubing. Annular seal means are carried in or on production tubing as it is run into a borehole. In conjunction with expansion of the tubing, the seal is deployed to form an annular isolator. An inflatable element carried on the tubing may be inflated with a fluid carried in the tubing and forced into the inflatable element during expansion of the tubing. Reactive chemicals may be carried in the tubing and injected into the annulus to react with each other and ambient fluids to increase in volume and harden into an annular seal. An elastomeric sleeve, ring or band carried on the tubing may be expanded into contact with a borehole wall and may have its radial dimension increased in conjunction with tubing expansion to form an annular isolator.

Abstract: The present disclosure addressed apparatus and methods for forming an annular isolator in a borehole after installation of production tubing. Annular seal means are carried in or on production tubing as it is run into a borehole. In conjunction with expansion of the tubing, the seal is deployed to form an annular isolator. An inflatable element carried on the tubing may be inflated with a fluid carried in the tubing and forced into the inflatable element during expansion of the tubing. Reactive chemicals may be carried in the tubing and injected into the annulus to react with each other and ambient fluids to increase in volume and harden into an annular seal. An elastomeric sleeve, ring or band carried on the tubing may be expanded into contact with a borehole wall and may have its radial dimension increased in conjunction with tubing expansion to form an annular isolator.

Abstract: The present disclosure addressed apparatus and methods for forming an annular isolator in a borehole after installation of production tubing. Annular seal means are carried in or on production tubing as it is run into a borehole. In conjunction with expansion of the tubing, the seal is deployed to form an annular isolator. An inflatable element carried on the tubing may be inflated with a fluid carried in the tubing and forced into the inflatable element during expansion of the tubing. Reactive chemicals may be carried in the tubing and injected into the annulus to react with each other and ambient fluids to increase in volume and harden into an annular seal. An elastomeric sleeve, ring or band carried on the tubing may be expanded into contact with a borehole wall and may have its radial dimension increased in conjunction with tubing expansion to form an annular isolator.

Abstract: A fluid loss device including a flapper and seat assembly that provide a seal on a lower flapper surface when the flapper is closed and resists pressure in either direction. The flapper and seat assembly is spring biased to contact a flapper support above the flapper to resist deformation of the flapper due to a pressure differential from below the flapper. The flapper and seat assembly may be moved by tubing pressure to release an opening prop that opens the flapper. The valve seat may include an elastomeric seal element to improve the fluid flow restriction. The flapper and seat assembly is also biased upward by a pressure differential from below to above the flapper, to thereby increase the flapper to valve seat pressure as the fluid pressure differential increases.

Abstract: An electromechanical transducer formed by an electrical and mechanical combination of a piezoelectric device and a magnetostrictive device. The two devices are electrically coupled so that their capacitive and inductive reactances approach a balance to provide an essentially resistive combined input at a selected frequency. Efficiency of circuits driving the transducer is improved. The devices are mechanically coupled so that the mechanical outputs add or reinforce each other. Two transducer pairs may be used in a two frequency telemetry system with each pair tuned to one of the frequencies for optimal reactance balancing and transduction efficiency.

Abstract: In accordance with the present invention, an apparatus and method are provided which utilize an expandable media assembly to create an annular barrier in a subterranean well. The apparatus comprises a tubing assembly for placement in the wellbore, the tubing assembly having an outer surface creating an annular space with the wellbore when the tubing assembly is placed in the wellbore. The apparatus has an expandable media assembly having an expandable material. The expandable material is initially in a run-in position and is capable of increasing in volume to a set position in the wellbore thereby creating an annular barrier blocking fluid flow along the annular space. The expandable material can be a foam, gel, or alloy. The media can be deformable upon enlargement and conform to the wellbore wall. The media can be a sleeve secured to the tubular assembly or a medium carried in a pressurized canister for release at a selected location downhole.

Abstract: The present disclosure addressed apparatus and methods for forming an annular isolator in a borehole after installation of production tubing. Annular seal means are carried in or on production tubing as it is run into a borehole. In conjunction with expansion of the tubing, the seal is deployed to form an annular isolator. An inflatable element carried on the tubing may be inflated with a fluid carried in the tubing and forced into the inflatable element during expansion of the tubing. Reactive chemicals may be carried in the tubing and injected into the annulus to react with each other and ambient fluids to increase in volume and harden into an annular seal. An elastomeric sleeve, ring or band carried on the tubing may be expanded into contact with a borehole wall and may have its radial dimension increased in conjunction with tubing expansion to form an annular isolator.

Abstract: A system and method for dynamically calibrating signals from a quartz pressure sensor to correct for temperature transients. A series of differences of time spaced temperature readings is stored in a tapped delay line and coupled to a transfer function. The transfer function uses the temperature difference values to correct pressure frequency readings for temperature transient errors. In one form, one transfer function uses temperature and pressure readings to statically calibrate pressure readings and a second transfer function uses temperature differences to provide a temperature transient correction which is added to the statically calibrated pressure value.

Abstract: A method and apparatus for in-situ characterization of downhole fluids in a wellbore using ultrasonic acoustic signals. Measurements of the speed of sound, attenuation of the signal, and acoustic back-scattering are used to provide qualitative and quantitative data as to the composition, nature of solid particulates, compressibility, bubble point, and the oil/water ratio of the fluid. The tool generally comprises three sets of acoustic transducers mounted perpendicular to the direction of the flow. These transducers are capable of operating at different frequencies so that the spectrum of the acoustic signal can be optimized. The apparatus is capable of operating downhole to provide real time information as to conditions in the well.

Abstract: A circular shaped charge and methods of manufacture, shipping and assembly. An circular shaped charge is manufactured as two separate charge halves, upper and lower, and a separate continuous liner or pair of continuous half liners. Preferably, each charge half is formed of a number of segments, each comprising a reduced weight of explosive which can be shipped under preferred regulations. The explosive contains sufficient binder to prevent damage to the charge segments during shipping and assembly at a job site. The separately shipped components are assembled at the job site to form a complete circular shaped charge useful, for example, in a tubing cutter.

Abstract: Disclosed is a system for using pressure differential between completion fluid in an oil well and produced fluids to power downhole devices, including instruments and actuators. A conduit is provided bypassing a packer which seals a production string to a well casing. A control system, including a flow valve, allows fluid to flow to an electrical generator as needed to charge an electrical storage device. Downhole electrically operated devices, e.g. a temperature sensor and signal transmitter, draw power from the storage device. Alternatively, fluid may also be directed to hydraulically driven actuators to, for example, operate a production fluid control valve.

Abstract: A manually operated manhole cover lifter comprising two substantially linear members connected by a pivot in the form of scissors or tongs. The lower end of each member has a hook adapted for engaging a cover recess and the upper end has a handle for manual engagement. The hook angles are selected together with the pivot to hook distance to provide secure engagement of the cover when the hooks are inserted into cover apertures. The tool may be used by one or two people standing in an upright position to lift and move a cover from, or place a cover on, a manhole.

Abstract: Method and apparatus for producing a first zone through a wellbore while simultaneously injecting gas into a second zone through the same wellbore. The production stream is produced to the surface through a string of tubing where gas is separated therefrom. The separated gas and/or gas from another source is then mixed with a carrier fluid (e.g. produced water, etc.) to form a mixture which, in turn, is pumped down the well annulus and through a downhole separator (e.g. an inverted hydrocyclone) where at least a portion of the gas is separated from the mixture. The separated gas is injected into the second zone while the remaining mixture is commingled with the production stream before the combined streams flow to the surface through the tubing.

Abstract: A method for determined porosity of an earth formation surrounding a borehole without prior knowledge of formation lithology. Neutron logging tools are used to measure thermal neutron porosity, epithermal neutron porosity and formation absorption cross section. Two calculating methods are used for a series of assumed porosity values to calculate matrix diffusion length. Matrix diffusion lengths calculated by the two methods are compared to find the highest assumed porosity for which the calculated diffusion lengths are substantially the same. This highest porosity value is the actual formation porosity.

Abstract: A method for generating improved displays of seismic data by processing seismic amplitude versus offset data to correct for overburden effects. Analytic traces are calculated for the zero offset reflectivity, A, trace and the amplitude versus offset slope, B, trace of the AVO data. Statistics for the A and B traces within a selected window in time and common depth point space about a selected sample point are calculated. The statistics include root mean square amplitudes of the A and B traces and the correlation coefficient. Desired statistics are selected and used with the measured statistics to correct the A and B traces.

Abstract: An improved method for stimulating coal degasification wells comprising the injection of a foam into a coal seam which contains natural or induced fractures. Thereafter, high pressure gas is injected into the coal seam and suddenly released to cause disintegration of coal surrounding the borehole.

Abstract: A method for displaying seismic data to provide direct indications of the presence of hydrocarbons. Seismic data is processed using conventional amplitude versus offset techniques to obtain zero offset reflectivity, or A, traces and the amplitude versus offset slope, or B, traces. AB cross plots of each trace are then generated. Each sample point on the cross plot is then assigned a value corresponding to its deviation from the regression line of the cross plotted AB points. The assigned values are then plotted in their corresponding time sample positions to generate a trace or display providing a direct indication of hydrocarbons.

Abstract: In a method of logging a well in a subterranean formation which formation has been fractured by injecting proppant tagged with at least one radioactive material into the formation through the well, the improvement comprising: utilizing a spectral gamma-ray tool in performing the logging. By analyzing one or more selected ratios of counting rates at certain energy areas of the spectrum one can determine the vertical height of the fracturing in the formation.

Abstract: A method for producing isostatically corrected gravity displays using available gravity data sets. The values of crustal density, density contrast between lower crust and mantle, and crustal thickness at sea level required for the Airy-Heiskanen equation are determined by analysis of the data set. Crustal density is determined by fractal analysis. Density contrast is determined by cross plotting Bouguer anomaly values versus elevation. Crustal thickness is determined by plotting power spectra of free-air gravity grids. The values are then used in the Airy-Heiskanen equation to provide the value of depth to crust-mantle boundary at each data point location in order to make accurate isostatic corrections and to produce accurate isostatically corrected displays.

Abstract: A marine seismic bottom geophone anchor and coupling device comprising two rectangular fabric sections attached along their edges and along a plurality of lines between edges to form a plurality of pockets. The pockets are filled with a weighting material. Connecting means are provided so that when the combined fabric sections are wrapped around a marine seismic bottom geophone, it will be held in a generally cylindrical form to simultaneously anchor the geophones and associated cables at a desired marine bottom location, isolate the sensors from noise sources, and provide good coupling to the marine bottom for receiving desired seismic signals.